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Commit 5e24f358 authored by Roger Leigh's avatar Roger Leigh Committed by Jesse Beder
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test: Upgrade googlemock 1.7.0 to googletest 1.8.0 

Note that with the release of 1.8.0, googlemock and
googletest are unified into a single release.
parent e2818c42
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Showing with 3726 additions and 6 deletions
test/gmock-1.7.0/gtest/Makefile.am → test/gtest-1.8.0/googletest/Makefile.am
View file @ 5e24f358
...@@ -205,9 +205,13 @@ pkginclude_internal_HEADERS = \ ...@@ -205,9 +205,13 @@ pkginclude_internal_HEADERS = \
include/gtest/internal/gtest-param-util-generated.h \ include/gtest/internal/gtest-param-util-generated.h \
include/gtest/internal/gtest-param-util.h \ include/gtest/internal/gtest-param-util.h \
include/gtest/internal/gtest-port.h \ include/gtest/internal/gtest-port.h \
include/gtest/internal/gtest-port-arch.h \
include/gtest/internal/gtest-string.h \ include/gtest/internal/gtest-string.h \
include/gtest/internal/gtest-tuple.h \ include/gtest/internal/gtest-tuple.h \
include/gtest/internal/gtest-type-util.h include/gtest/internal/gtest-type-util.h \
include/gtest/internal/custom/gtest.h \
include/gtest/internal/custom/gtest-port.h \
include/gtest/internal/custom/gtest-printers.h
lib_libgtest_main_la_SOURCES = src/gtest_main.cc lib_libgtest_main_la_SOURCES = src/gtest_main.cc
lib_libgtest_main_la_LIBADD = lib/libgtest.la lib_libgtest_main_la_LIBADD = lib/libgtest.la
......
test/gmock-1.7.0/gtest/README → test/gtest-1.8.0/googletest/README.md
View file @ 5e24f358
Google C++ Testing Framework
============================
http://code.google.com/p/googletest/ ### Generic Build Instructions ###
Overview
--------
Google's framework for writing C++ tests on a variety of platforms
(Linux, Mac OS X, Windows, Windows CE, Symbian, etc). Based on the
xUnit architecture. Supports automatic test discovery, a rich set of
assertions, user-defined assertions, death tests, fatal and non-fatal
failures, various options for running the tests, and XML test report
generation.
Please see the project page above for more information as well as the
mailing list for questions, discussions, and development. There is
also an IRC channel on OFTC (irc.oftc.net) #gtest available. Please
join us!
Requirements for End Users
--------------------------
Google Test is designed to have fairly minimal requirements to build
and use with your projects, but there are some. Currently, we support
Linux, Windows, Mac OS X, and Cygwin. We will also make our best
effort to support other platforms (e.g. Solaris, AIX, and z/OS).
However, since core members of the Google Test project have no access
to these platforms, Google Test may have outstanding issues there. If
you notice any problems on your platform, please notify
googletestframework@googlegroups.com. Patches for fixing them are
even more welcome!
### Linux Requirements ###
These are the base requirements to build and use Google Test from a source
package (as described below):
* GNU-compatible Make or gmake
* POSIX-standard shell
* POSIX(-2) Regular Expressions (regex.h)
* A C++98-standard-compliant compiler
### Windows Requirements ###
* Microsoft Visual C++ 7.1 or newer
### Cygwin Requirements ###
* Cygwin 1.5.25-14 or newer
### Mac OS X Requirements ###
* Mac OS X 10.4 Tiger or newer
* Developer Tools Installed
Also, you'll need CMake 2.6.4 or higher if you want to build the
samples using the provided CMake script, regardless of the platform.
Requirements for Contributors
-----------------------------
We welcome patches. If you plan to contribute a patch, you need to
build Google Test and its own tests from an SVN checkout (described
below), which has further requirements:
* Python version 2.3 or newer (for running some of the tests and
re-generating certain source files from templates)
* CMake 2.6.4 or newer
Getting the Source
------------------
There are two primary ways of getting Google Test's source code: you
can download a stable source release in your preferred archive format,
or directly check out the source from our Subversion (SVN) repositary.
The SVN checkout requires a few extra steps and some extra software
packages on your system, but lets you track the latest development and
make patches much more easily, so we highly encourage it.
### Source Package ###
Google Test is released in versioned source packages which can be
downloaded from the download page [1]. Several different archive
formats are provided, but the only difference is the tools used to
manipulate them, and the size of the resulting file. Download
whichever you are most comfortable with.
[1] http://code.google.com/p/googletest/downloads/list
Once the package is downloaded, expand it using whichever tools you
prefer for that type. This will result in a new directory with the
name "gtest-X.Y.Z" which contains all of the source code. Here are
some examples on Linux:
tar -xvzf gtest-X.Y.Z.tar.gz
tar -xvjf gtest-X.Y.Z.tar.bz2
unzip gtest-X.Y.Z.zip
### SVN Checkout ###
To check out the main branch (also known as the "trunk") of Google
Test, run the following Subversion command:
svn checkout http://googletest.googlecode.com/svn/trunk/ gtest-svn
Setting up the Build #### Setup ####
--------------------
To build Google Test and your tests that use it, you need to tell your To build Google Test and your tests that use it, you need to tell your
build system where to find its headers and source files. The exact build system where to find its headers and source files. The exact
way to do it depends on which build system you use, and is usually way to do it depends on which build system you use, and is usually
straightforward. straightforward.
### Generic Build Instructions ### #### Build ####
Suppose you put Google Test in directory ${GTEST_DIR}. To build it, Suppose you put Google Test in directory `${GTEST_DIR}`. To build it,
create a library build target (or a project as called by Visual Studio create a library build target (or a project as called by Visual Studio
and Xcode) to compile and Xcode) to compile
${GTEST_DIR}/src/gtest-all.cc ${GTEST_DIR}/src/gtest-all.cc
with ${GTEST_DIR}/include in the system header search path and ${GTEST_DIR} with `${GTEST_DIR}/include` in the system header search path and `${GTEST_DIR}`
in the normal header search path. Assuming a Linux-like system and gcc, in the normal header search path. Assuming a Linux-like system and gcc,
something like the following will do: something like the following will do:
g++ -isystem ${GTEST_DIR}/include -I${GTEST_DIR} \ g++ -isystem ${GTEST_DIR}/include -I${GTEST_DIR} \
-pthread -c ${GTEST_DIR}/src/gtest-all.cc -pthread -c ${GTEST_DIR}/src/gtest-all.cc
ar -rv libgtest.a gtest-all.o ar -rv libgtest.a gtest-all.o
(We need -pthread as Google Test uses threads.) (We need `-pthread` as Google Test uses threads.)
Next, you should compile your test source file with Next, you should compile your test source file with
${GTEST_DIR}/include in the system header search path, and link it `${GTEST_DIR}/include` in the system header search path, and link it
with gtest and any other necessary libraries: with gtest and any other necessary libraries:
g++ -isystem ${GTEST_DIR}/include -pthread path/to/your_test.cc libgtest.a \ g++ -isystem ${GTEST_DIR}/include -pthread path/to/your_test.cc libgtest.a \
-o your_test -o your_test
As an example, the make/ directory contains a Makefile that you can As an example, the make/ directory contains a Makefile that you can
use to build Google Test on systems where GNU make is available use to build Google Test on systems where GNU make is available
...@@ -146,42 +43,42 @@ script. ...@@ -146,42 +43,42 @@ script.
If the default settings are correct for your environment, the If the default settings are correct for your environment, the
following commands should succeed: following commands should succeed:
cd ${GTEST_DIR}/make cd ${GTEST_DIR}/make
make make
./sample1_unittest ./sample1_unittest
If you see errors, try to tweak the contents of make/Makefile to make If you see errors, try to tweak the contents of `make/Makefile` to make
them go away. There are instructions in make/Makefile on how to do them go away. There are instructions in `make/Makefile` on how to do
it. it.
### Using CMake ### ### Using CMake ###
Google Test comes with a CMake build script (CMakeLists.txt) that can Google Test comes with a CMake build script (
be used on a wide range of platforms ("C" stands for cross-platofrm.). [CMakeLists.txt](CMakeLists.txt)) that can be used on a wide range of platforms ("C" stands for
If you don't have CMake installed already, you can download it for cross-platform.). If you don't have CMake installed already, you can
free from http://www.cmake.org/. download it for free from <http://www.cmake.org/>.
CMake works by generating native makefiles or build projects that can CMake works by generating native makefiles or build projects that can
be used in the compiler environment of your choice. The typical be used in the compiler environment of your choice. The typical
workflow starts with: workflow starts with:
mkdir mybuild # Create a directory to hold the build output. mkdir mybuild # Create a directory to hold the build output.
cd mybuild cd mybuild
cmake ${GTEST_DIR} # Generate native build scripts. cmake ${GTEST_DIR} # Generate native build scripts.
If you want to build Google Test's samples, you should replace the If you want to build Google Test's samples, you should replace the
last command with last command with
cmake -Dgtest_build_samples=ON ${GTEST_DIR} cmake -Dgtest_build_samples=ON ${GTEST_DIR}
If you are on a *nix system, you should now see a Makefile in the If you are on a \*nix system, you should now see a Makefile in the
current directory. Just type 'make' to build gtest. current directory. Just type 'make' to build gtest.
If you use Windows and have Vistual Studio installed, a gtest.sln file If you use Windows and have Visual Studio installed, a `gtest.sln` file
and several .vcproj files will be created. You can then build them and several `.vcproj` files will be created. You can then build them
using Visual Studio. using Visual Studio.
On Mac OS X with Xcode installed, a .xcodeproj file will be generated. On Mac OS X with Xcode installed, a `.xcodeproj` file will be generated.
### Legacy Build Scripts ### ### Legacy Build Scripts ###
...@@ -195,7 +92,7 @@ with your existing build system. ...@@ -195,7 +92,7 @@ with your existing build system.
If you still need to use the legacy build scripts, here's how: If you still need to use the legacy build scripts, here's how:
The msvc\ folder contains two solutions with Visual C++ projects. The msvc\ folder contains two solutions with Visual C++ projects.
Open the gtest.sln or gtest-md.sln file using Visual Studio, and you Open the `gtest.sln` or `gtest-md.sln` file using Visual Studio, and you
are ready to build Google Test the same way you build any Visual are ready to build Google Test the same way you build any Visual
Studio project. Files that have names ending with -md use DLL Studio project. Files that have names ending with -md use DLL
versions of Microsoft runtime libraries (the /MD or the /MDd compiler versions of Microsoft runtime libraries (the /MD or the /MDd compiler
...@@ -205,13 +102,13 @@ the same option to compile both gtest and the test code. If you use ...@@ -205,13 +102,13 @@ the same option to compile both gtest and the test code. If you use
Visual Studio 2005 or above, we recommend the -md version as /MD is Visual Studio 2005 or above, we recommend the -md version as /MD is
the default for new projects in these versions of Visual Studio. the default for new projects in these versions of Visual Studio.
On Mac OS X, open the gtest.xcodeproj in the xcode/ folder using On Mac OS X, open the `gtest.xcodeproj` in the `xcode/` folder using
Xcode. Build the "gtest" target. The universal binary framework will Xcode. Build the "gtest" target. The universal binary framework will
end up in your selected build directory (selected in the Xcode end up in your selected build directory (selected in the Xcode
"Preferences..." -> "Building" pane and defaults to xcode/build). "Preferences..." -> "Building" pane and defaults to xcode/build).
Alternatively, at the command line, enter: Alternatively, at the command line, enter:
xcodebuild xcodebuild
This will build the "Release" configuration of gtest.framework in your This will build the "Release" configuration of gtest.framework in your
default build location. See the "xcodebuild" man page for more default build location. See the "xcodebuild" man page for more
...@@ -220,26 +117,26 @@ different locations. ...@@ -220,26 +117,26 @@ different locations.
If you wish to use the Google Test Xcode project with Xcode 4.x and If you wish to use the Google Test Xcode project with Xcode 4.x and
above, you need to either: above, you need to either:
* update the SDK configuration options in xcode/Config/General.xconfig. * update the SDK configuration options in xcode/Config/General.xconfig.
Comment options SDKROOT, MACOS_DEPLOYMENT_TARGET, and GCC_VERSION. If Comment options `SDKROOT`, `MACOS_DEPLOYMENT_TARGET`, and `GCC_VERSION`. If
you choose this route you lose the ability to target earlier versions you choose this route you lose the ability to target earlier versions
of MacOS X. of MacOS X.
* Install an SDK for an earlier version. This doesn't appear to be * Install an SDK for an earlier version. This doesn't appear to be
supported by Apple, but has been reported to work supported by Apple, but has been reported to work
(http://stackoverflow.com/questions/5378518). (http://stackoverflow.com/questions/5378518).
Tweaking Google Test ### Tweaking Google Test ###
--------------------
Google Test can be used in diverse environments. The default Google Test can be used in diverse environments. The default
configuration may not work (or may not work well) out of the box in configuration may not work (or may not work well) out of the box in
some environments. However, you can easily tweak Google Test by some environments. However, you can easily tweak Google Test by
defining control macros on the compiler command line. Generally, defining control macros on the compiler command line. Generally,
these macros are named like GTEST_XYZ and you define them to either 1 these macros are named like `GTEST_XYZ` and you define them to either 1
or 0 to enable or disable a certain feature. or 0 to enable or disable a certain feature.
We list the most frequently used macros below. For a complete list, We list the most frequently used macros below. For a complete list,
see file include/gtest/internal/gtest-port.h. see file [include/gtest/internal/gtest-port.h](include/gtest/internal/gtest-port.h).
### Choosing a TR1 Tuple Library ### ### Choosing a TR1 Tuple Library ###
...@@ -255,36 +152,36 @@ tell Google Test to use the same TR1 tuple library the rest of your ...@@ -255,36 +152,36 @@ tell Google Test to use the same TR1 tuple library the rest of your
project uses, or the two tuple implementations will clash. To do project uses, or the two tuple implementations will clash. To do
that, add that, add
-DGTEST_USE_OWN_TR1_TUPLE=0 -DGTEST_USE_OWN_TR1_TUPLE=0
to the compiler flags while compiling Google Test and your tests. If to the compiler flags while compiling Google Test and your tests. If
you want to force Google Test to use its own tuple library, just add you want to force Google Test to use its own tuple library, just add
-DGTEST_USE_OWN_TR1_TUPLE=1 -DGTEST_USE_OWN_TR1_TUPLE=1
to the compiler flags instead. to the compiler flags instead.
If you don't want Google Test to use tuple at all, add If you don't want Google Test to use tuple at all, add
-DGTEST_HAS_TR1_TUPLE=0 -DGTEST_HAS_TR1_TUPLE=0
and all features using tuple will be disabled. and all features using tuple will be disabled.
### Multi-threaded Tests ### ### Multi-threaded Tests ###
Google Test is thread-safe where the pthread library is available. Google Test is thread-safe where the pthread library is available.
After #include "gtest/gtest.h", you can check the GTEST_IS_THREADSAFE After `#include "gtest/gtest.h"`, you can check the `GTEST_IS_THREADSAFE`
macro to see whether this is the case (yes if the macro is #defined to macro to see whether this is the case (yes if the macro is `#defined` to
1, no if it's undefined.). 1, no if it's undefined.).
If Google Test doesn't correctly detect whether pthread is available If Google Test doesn't correctly detect whether pthread is available
in your environment, you can force it with in your environment, you can force it with
-DGTEST_HAS_PTHREAD=1 -DGTEST_HAS_PTHREAD=1
or or
-DGTEST_HAS_PTHREAD=0 -DGTEST_HAS_PTHREAD=0
When Google Test uses pthread, you may need to add flags to your When Google Test uses pthread, you may need to add flags to your
compiler and/or linker to select the pthread library, or you'll get compiler and/or linker to select the pthread library, or you'll get
...@@ -301,7 +198,7 @@ as a shared library (known as a DLL on Windows) if you prefer. ...@@ -301,7 +198,7 @@ as a shared library (known as a DLL on Windows) if you prefer.
To compile *gtest* as a shared library, add To compile *gtest* as a shared library, add
-DGTEST_CREATE_SHARED_LIBRARY=1 -DGTEST_CREATE_SHARED_LIBRARY=1
to the compiler flags. You'll also need to tell the linker to produce to the compiler flags. You'll also need to tell the linker to produce
a shared library instead - consult your linker's manual for how to do a shared library instead - consult your linker's manual for how to do
...@@ -309,14 +206,14 @@ it. ...@@ -309,14 +206,14 @@ it.
To compile your *tests* that use the gtest shared library, add To compile your *tests* that use the gtest shared library, add
-DGTEST_LINKED_AS_SHARED_LIBRARY=1 -DGTEST_LINKED_AS_SHARED_LIBRARY=1
to the compiler flags. to the compiler flags.
Note: while the above steps aren't technically necessary today when Note: while the above steps aren't technically necessary today when
using some compilers (e.g. GCC), they may become necessary in the using some compilers (e.g. GCC), they may become necessary in the
future, if we decide to improve the speed of loading the library (see future, if we decide to improve the speed of loading the library (see
http://gcc.gnu.org/wiki/Visibility for details). Therefore you are <http://gcc.gnu.org/wiki/Visibility> for details). Therefore you are
recommended to always add the above flags when using Google Test as a recommended to always add the above flags when using Google Test as a
shared library. Otherwise a future release of Google Test may break shared library. Otherwise a future release of Google Test may break
your build script. your build script.
...@@ -324,7 +221,7 @@ your build script. ...@@ -324,7 +221,7 @@ your build script.
### Avoiding Macro Name Clashes ### ### Avoiding Macro Name Clashes ###
In C++, macros don't obey namespaces. Therefore two libraries that In C++, macros don't obey namespaces. Therefore two libraries that
both define a macro of the same name will clash if you #include both both define a macro of the same name will clash if you `#include` both
definitions. In case a Google Test macro clashes with another definitions. In case a Google Test macro clashes with another
library, you can force Google Test to rename its macro to avoid the library, you can force Google Test to rename its macro to avoid the
conflict. conflict.
...@@ -332,53 +229,22 @@ conflict. ...@@ -332,53 +229,22 @@ conflict.
Specifically, if both Google Test and some other code define macro Specifically, if both Google Test and some other code define macro
FOO, you can add FOO, you can add
-DGTEST_DONT_DEFINE_FOO=1 -DGTEST_DONT_DEFINE_FOO=1
to the compiler flags to tell Google Test to change the macro's name to the compiler flags to tell Google Test to change the macro's name
from FOO to GTEST_FOO. Currently FOO can be FAIL, SUCCEED, or TEST. from `FOO` to `GTEST_FOO`. Currently `FOO` can be `FAIL`, `SUCCEED`,
For example, with -DGTEST_DONT_DEFINE_TEST=1, you'll need to write or `TEST`. For example, with `-DGTEST_DONT_DEFINE_TEST=1`, you'll
need to write
GTEST_TEST(SomeTest, DoesThis) { ... } GTEST_TEST(SomeTest, DoesThis) { ... }
instead of instead of
TEST(SomeTest, DoesThis) { ... } TEST(SomeTest, DoesThis) { ... }
in order to define a test. in order to define a test.
Upgrating from an Earlier Version ## Developing Google Test ##
---------------------------------
We strive to keep Google Test releases backward compatible.
Sometimes, though, we have to make some breaking changes for the
users' long-term benefits. This section describes what you'll need to
do if you are upgrading from an earlier version of Google Test.
### Upgrading from 1.3.0 or Earlier ###
You may need to explicitly enable or disable Google Test's own TR1
tuple library. See the instructions in section "Choosing a TR1 Tuple
Library".
### Upgrading from 1.4.0 or Earlier ###
The Autotools build script (configure + make) is no longer officially
supportted. You are encouraged to migrate to your own build system or
use CMake. If you still need to use Autotools, you can find
instructions in the README file from Google Test 1.4.0.
On platforms where the pthread library is available, Google Test uses
it in order to be thread-safe. See the "Multi-threaded Tests" section
for what this means to your build script.
If you use Microsoft Visual C++ 7.1 with exceptions disabled, Google
Test will no longer compile. This should affect very few people, as a
large portion of STL (including <string>) doesn't compile in this mode
anyway. We decided to stop supporting it in order to greatly simplify
Google Test's implementation.
Developing Google Test
----------------------
This section discusses how to make your own changes to Google Test. This section discusses how to make your own changes to Google Test.
...@@ -388,48 +254,27 @@ To make sure your changes work as intended and don't break existing ...@@ -388,48 +254,27 @@ To make sure your changes work as intended and don't break existing
functionality, you'll want to compile and run Google Test's own tests. functionality, you'll want to compile and run Google Test's own tests.
For that you can use CMake: For that you can use CMake:
mkdir mybuild mkdir mybuild
cd mybuild cd mybuild
cmake -Dgtest_build_tests=ON ${GTEST_DIR} cmake -Dgtest_build_tests=ON ${GTEST_DIR}
Make sure you have Python installed, as some of Google Test's tests Make sure you have Python installed, as some of Google Test's tests
are written in Python. If the cmake command complains about not being are written in Python. If the cmake command complains about not being
able to find Python ("Could NOT find PythonInterp (missing: able to find Python (`Could NOT find PythonInterp (missing:
PYTHON_EXECUTABLE)"), try telling it explicitly where your Python PYTHON_EXECUTABLE)`), try telling it explicitly where your Python
executable can be found: executable can be found:
cmake -DPYTHON_EXECUTABLE=path/to/python -Dgtest_build_tests=ON ${GTEST_DIR} cmake -DPYTHON_EXECUTABLE=path/to/python -Dgtest_build_tests=ON ${GTEST_DIR}
Next, you can build Google Test and all of its own tests. On *nix, Next, you can build Google Test and all of its own tests. On \*nix,
this is usually done by 'make'. To run the tests, do this is usually done by 'make'. To run the tests, do
make test make test
All tests should pass. All tests should pass.
### Regenerating Source Files ###
Some of Google Test's source files are generated from templates (not
in the C++ sense) using a script. A template file is named FOO.pump,
where FOO is the name of the file it will generate. For example, the
file include/gtest/internal/gtest-type-util.h.pump is used to generate
gtest-type-util.h in the same directory.
Normally you don't need to worry about regenerating the source files, Normally you don't need to worry about regenerating the source files,
unless you need to modify them. In that case, you should modify the unless you need to modify them. In that case, you should modify the
corresponding .pump files instead and run the pump.py Python script to corresponding .pump files instead and run the pump.py Python script to
regenerate them. You can find pump.py in the scripts/ directory. regenerate them. You can find pump.py in the [scripts/](scripts/) directory.
Read the Pump manual [2] for how to use it. Read the [Pump manual](docs/PumpManual.md) for how to use it.
[2] http://code.google.com/p/googletest/wiki/PumpManual
### Contributing a Patch ###
We welcome patches. Please read the Google Test developer's guide [3]
for how you can contribute. In particular, make sure you have signed
the Contributor License Agreement, or we won't be able to accept the
patch.
[3] http://code.google.com/p/googletest/wiki/GoogleTestDevGuide
Happy testing!
test/gmock-1.7.0/gtest/cmake/internal_utils.cmake → test/gtest-1.8.0/googletest/cmake/internal_utils.cmake
View file @ 5e24f358
...@@ -37,7 +37,7 @@ macro(fix_default_compiler_settings_) ...@@ -37,7 +37,7 @@ macro(fix_default_compiler_settings_)
# We prefer more strict warning checking for building Google Test. # We prefer more strict warning checking for building Google Test.
# Replaces /W3 with /W4 in defaults. # Replaces /W3 with /W4 in defaults.
string(REPLACE "/W3" "-W4" ${flag_var} "${${flag_var}}") string(REPLACE "/W3" "/W4" ${flag_var} "${${flag_var}}")
endforeach() endforeach()
endif() endif()
endmacro() endmacro()
...@@ -55,8 +55,8 @@ macro(config_compiler_and_linker) ...@@ -55,8 +55,8 @@ macro(config_compiler_and_linker)
if (MSVC) if (MSVC)
# Newlines inside flags variables break CMake's NMake generator. # Newlines inside flags variables break CMake's NMake generator.
# TODO(vladl@google.com): Add -RTCs and -RTCu to debug builds. # TODO(vladl@google.com): Add -RTCs and -RTCu to debug builds.
set(cxx_base_flags "-GS -W4 -WX -wd4127 -wd4251 -wd4275 -nologo -J -Zi") set(cxx_base_flags "-GS -W4 -WX -wd4251 -wd4275 -nologo -J -Zi")
if (MSVC_VERSION LESS 1400) if (MSVC_VERSION LESS 1400) # 1400 is Visual Studio 2005
# Suppress spurious warnings MSVC 7.1 sometimes issues. # Suppress spurious warnings MSVC 7.1 sometimes issues.
# Forcing value to bool. # Forcing value to bool.
set(cxx_base_flags "${cxx_base_flags} -wd4800") set(cxx_base_flags "${cxx_base_flags} -wd4800")
...@@ -66,6 +66,25 @@ macro(config_compiler_and_linker) ...@@ -66,6 +66,25 @@ macro(config_compiler_and_linker)
# Resolved overload was found by argument-dependent lookup. # Resolved overload was found by argument-dependent lookup.
set(cxx_base_flags "${cxx_base_flags} -wd4675") set(cxx_base_flags "${cxx_base_flags} -wd4675")
endif() endif()
if (MSVC_VERSION LESS 1500) # 1500 is Visual Studio 2008
# Conditional expression is constant.
# When compiling with /W4, we get several instances of C4127
# (Conditional expression is constant). In our code, we disable that
# warning on a case-by-case basis. However, on Visual Studio 2005,
# the warning fires on std::list. Therefore on that compiler and earlier,
# we disable the warning project-wide.
set(cxx_base_flags "${cxx_base_flags} -wd4127")
endif()
if (NOT (MSVC_VERSION LESS 1700)) # 1700 is Visual Studio 2012.
# Suppress "unreachable code" warning on VS 2012 and later.
# http://stackoverflow.com/questions/3232669 explains the issue.
set(cxx_base_flags "${cxx_base_flags} -wd4702")
endif()
if (NOT (MSVC_VERSION GREATER 1900)) # 1900 is Visual Studio 2015
# BigObj required for tests.
set(cxx_base_flags "${cxx_base_flags} -bigobj")
endif()
set(cxx_base_flags "${cxx_base_flags} -D_UNICODE -DUNICODE -DWIN32 -D_WIN32") set(cxx_base_flags "${cxx_base_flags} -D_UNICODE -DUNICODE -DWIN32 -D_WIN32")
set(cxx_base_flags "${cxx_base_flags} -DSTRICT -DWIN32_LEAN_AND_MEAN") set(cxx_base_flags "${cxx_base_flags} -DSTRICT -DWIN32_LEAN_AND_MEAN")
set(cxx_exception_flags "-EHsc -D_HAS_EXCEPTIONS=1") set(cxx_exception_flags "-EHsc -D_HAS_EXCEPTIONS=1")
...@@ -220,8 +239,16 @@ function(py_test name) ...@@ -220,8 +239,16 @@ function(py_test name)
# directly bind it from cmake. ${CTEST_CONFIGURATION_TYPE} is known # directly bind it from cmake. ${CTEST_CONFIGURATION_TYPE} is known
# only at ctest runtime (by calling ctest -c <Configuration>), so # only at ctest runtime (by calling ctest -c <Configuration>), so
# we have to escape $ to delay variable substitution here. # we have to escape $ to delay variable substitution here.
add_test(${name} if (${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION} GREATER 3.1)
${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/test/${name}.py add_test(
NAME ${name}
COMMAND ${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/test/${name}.py
--build_dir=${CMAKE_CURRENT_BINARY_DIR}/$<CONFIGURATION>)
else (${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION} GREATER 3.1)
add_test(
${name}
${PYTHON_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/test/${name}.py
--build_dir=${CMAKE_CURRENT_BINARY_DIR}/\${CTEST_CONFIGURATION_TYPE}) --build_dir=${CMAKE_CURRENT_BINARY_DIR}/\${CTEST_CONFIGURATION_TYPE})
endif (${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION} GREATER 3.1)
endif() endif()
endfunction() endfunction()
test/gtest-1.8.0/googletest/docs/AdvancedGuide.md 0 → 100644
View file @ 5e24f358
Now that you have read [Primer](Primer.md) and learned how to write tests
using Google Test, it's time to learn some new tricks. This document
will show you more assertions as well as how to construct complex
failure messages, propagate fatal failures, reuse and speed up your
test fixtures, and use various flags with your tests.
# More Assertions #
This section covers some less frequently used, but still significant,
assertions.
## Explicit Success and Failure ##
These three assertions do not actually test a value or expression. Instead,
they generate a success or failure directly. Like the macros that actually
perform a test, you may stream a custom failure message into the them.
| `SUCCEED();` |
|:-------------|
Generates a success. This does NOT make the overall test succeed. A test is
considered successful only if none of its assertions fail during its execution.
Note: `SUCCEED()` is purely documentary and currently doesn't generate any
user-visible output. However, we may add `SUCCEED()` messages to Google Test's
output in the future.
| `FAIL();` | `ADD_FAILURE();` | `ADD_FAILURE_AT("`_file\_path_`", `_line\_number_`);` |
|:-----------|:-----------------|:------------------------------------------------------|
`FAIL()` generates a fatal failure, while `ADD_FAILURE()` and `ADD_FAILURE_AT()` generate a nonfatal
failure. These are useful when control flow, rather than a Boolean expression,
deteremines the test's success or failure. For example, you might want to write
something like:
```
switch(expression) {
case 1: ... some checks ...
case 2: ... some other checks
...
default: FAIL() << "We shouldn't get here.";
}
```
Note: you can only use `FAIL()` in functions that return `void`. See the [Assertion Placement section](#assertion-placement) for more information.
_Availability_: Linux, Windows, Mac.
## Exception Assertions ##
These are for verifying that a piece of code throws (or does not
throw) an exception of the given type:
| **Fatal assertion** | **Nonfatal assertion** | **Verifies** |
|:--------------------|:-----------------------|:-------------|
| `ASSERT_THROW(`_statement_, _exception\_type_`);` | `EXPECT_THROW(`_statement_, _exception\_type_`);` | _statement_ throws an exception of the given type |
| `ASSERT_ANY_THROW(`_statement_`);` | `EXPECT_ANY_THROW(`_statement_`);` | _statement_ throws an exception of any type |
| `ASSERT_NO_THROW(`_statement_`);` | `EXPECT_NO_THROW(`_statement_`);` | _statement_ doesn't throw any exception |
Examples:
```
ASSERT_THROW(Foo(5), bar_exception);
EXPECT_NO_THROW({
int n = 5;
Bar(&n);
});
```
_Availability_: Linux, Windows, Mac; since version 1.1.0.
## Predicate Assertions for Better Error Messages ##
Even though Google Test has a rich set of assertions, they can never be
complete, as it's impossible (nor a good idea) to anticipate all the scenarios
a user might run into. Therefore, sometimes a user has to use `EXPECT_TRUE()`
to check a complex expression, for lack of a better macro. This has the problem
of not showing you the values of the parts of the expression, making it hard to
understand what went wrong. As a workaround, some users choose to construct the
failure message by themselves, streaming it into `EXPECT_TRUE()`. However, this
is awkward especially when the expression has side-effects or is expensive to
evaluate.
Google Test gives you three different options to solve this problem:
### Using an Existing Boolean Function ###
If you already have a function or a functor that returns `bool` (or a type
that can be implicitly converted to `bool`), you can use it in a _predicate
assertion_ to get the function arguments printed for free:
| **Fatal assertion** | **Nonfatal assertion** | **Verifies** |
|:--------------------|:-----------------------|:-------------|
| `ASSERT_PRED1(`_pred1, val1_`);` | `EXPECT_PRED1(`_pred1, val1_`);` | _pred1(val1)_ returns true |
| `ASSERT_PRED2(`_pred2, val1, val2_`);` | `EXPECT_PRED2(`_pred2, val1, val2_`);` | _pred2(val1, val2)_ returns true |
| ... | ... | ... |
In the above, _predn_ is an _n_-ary predicate function or functor, where
_val1_, _val2_, ..., and _valn_ are its arguments. The assertion succeeds
if the predicate returns `true` when applied to the given arguments, and fails
otherwise. When the assertion fails, it prints the value of each argument. In
either case, the arguments are evaluated exactly once.
Here's an example. Given
```
// Returns true iff m and n have no common divisors except 1.
bool MutuallyPrime(int m, int n) { ... }
const int a = 3;
const int b = 4;
const int c = 10;
```
the assertion `EXPECT_PRED2(MutuallyPrime, a, b);` will succeed, while the
assertion `EXPECT_PRED2(MutuallyPrime, b, c);` will fail with the message
<pre>
!MutuallyPrime(b, c) is false, where<br>
b is 4<br>
c is 10<br>
</pre>
**Notes:**
1. If you see a compiler error "no matching function to call" when using `ASSERT_PRED*` or `EXPECT_PRED*`, please see [this FAQ](FAQ.md#the-compiler-complains-no-matching-function-to-call-when-i-use-assert_predn-how-do-i-fix-it) for how to resolve it.
1. Currently we only provide predicate assertions of arity <= 5. If you need a higher-arity assertion, let us know.
_Availability_: Linux, Windows, Mac
### Using a Function That Returns an AssertionResult ###
While `EXPECT_PRED*()` and friends are handy for a quick job, the
syntax is not satisfactory: you have to use different macros for
different arities, and it feels more like Lisp than C++. The
`::testing::AssertionResult` class solves this problem.
An `AssertionResult` object represents the result of an assertion
(whether it's a success or a failure, and an associated message). You
can create an `AssertionResult` using one of these factory
functions:
```
namespace testing {
// Returns an AssertionResult object to indicate that an assertion has
// succeeded.
AssertionResult AssertionSuccess();
// Returns an AssertionResult object to indicate that an assertion has
// failed.
AssertionResult AssertionFailure();
}
```
You can then use the `<<` operator to stream messages to the
`AssertionResult` object.
To provide more readable messages in Boolean assertions
(e.g. `EXPECT_TRUE()`), write a predicate function that returns
`AssertionResult` instead of `bool`. For example, if you define
`IsEven()` as:
```
::testing::AssertionResult IsEven(int n) {
if ((n % 2) == 0)
return ::testing::AssertionSuccess();
else
return ::testing::AssertionFailure() << n << " is odd";
}
```
instead of:
```
bool IsEven(int n) {
return (n % 2) == 0;
}
```
the failed assertion `EXPECT_TRUE(IsEven(Fib(4)))` will print:
<pre>
Value of: IsEven(Fib(4))<br>
Actual: false (*3 is odd*)<br>
Expected: true<br>
</pre>
instead of a more opaque
<pre>
Value of: IsEven(Fib(4))<br>
Actual: false<br>
Expected: true<br>
</pre>
If you want informative messages in `EXPECT_FALSE` and `ASSERT_FALSE`
as well, and are fine with making the predicate slower in the success
case, you can supply a success message:
```
::testing::AssertionResult IsEven(int n) {
if ((n % 2) == 0)
return ::testing::AssertionSuccess() << n << " is even";
else
return ::testing::AssertionFailure() << n << " is odd";
}
```
Then the statement `EXPECT_FALSE(IsEven(Fib(6)))` will print
<pre>
Value of: IsEven(Fib(6))<br>
Actual: true (8 is even)<br>
Expected: false<br>
</pre>
_Availability_: Linux, Windows, Mac; since version 1.4.1.
### Using a Predicate-Formatter ###
If you find the default message generated by `(ASSERT|EXPECT)_PRED*` and
`(ASSERT|EXPECT)_(TRUE|FALSE)` unsatisfactory, or some arguments to your
predicate do not support streaming to `ostream`, you can instead use the
following _predicate-formatter assertions_ to _fully_ customize how the
message is formatted:
| **Fatal assertion** | **Nonfatal assertion** | **Verifies** |
|:--------------------|:-----------------------|:-------------|
| `ASSERT_PRED_FORMAT1(`_pred\_format1, val1_`);` | `EXPECT_PRED_FORMAT1(`_pred\_format1, val1_`);` | _pred\_format1(val1)_ is successful |
| `ASSERT_PRED_FORMAT2(`_pred\_format2, val1, val2_`);` | `EXPECT_PRED_FORMAT2(`_pred\_format2, val1, val2_`);` | _pred\_format2(val1, val2)_ is successful |
| `...` | `...` | `...` |
The difference between this and the previous two groups of macros is that instead of
a predicate, `(ASSERT|EXPECT)_PRED_FORMAT*` take a _predicate-formatter_
(_pred\_formatn_), which is a function or functor with the signature:
`::testing::AssertionResult PredicateFormattern(const char* `_expr1_`, const char* `_expr2_`, ... const char* `_exprn_`, T1 `_val1_`, T2 `_val2_`, ... Tn `_valn_`);`
where _val1_, _val2_, ..., and _valn_ are the values of the predicate
arguments, and _expr1_, _expr2_, ..., and _exprn_ are the corresponding
expressions as they appear in the source code. The types `T1`, `T2`, ..., and
`Tn` can be either value types or reference types. For example, if an
argument has type `Foo`, you can declare it as either `Foo` or `const Foo&`,
whichever is appropriate.
A predicate-formatter returns a `::testing::AssertionResult` object to indicate
whether the assertion has succeeded or not. The only way to create such an
object is to call one of these factory functions:
As an example, let's improve the failure message in the previous example, which uses `EXPECT_PRED2()`:
```
// Returns the smallest prime common divisor of m and n,
// or 1 when m and n are mutually prime.
int SmallestPrimeCommonDivisor(int m, int n) { ... }
// A predicate-formatter for asserting that two integers are mutually prime.
::testing::AssertionResult AssertMutuallyPrime(const char* m_expr,
const char* n_expr,
int m,
int n) {
if (MutuallyPrime(m, n))
return ::testing::AssertionSuccess();
return ::testing::AssertionFailure()
<< m_expr << " and " << n_expr << " (" << m << " and " << n
<< ") are not mutually prime, " << "as they have a common divisor "
<< SmallestPrimeCommonDivisor(m, n);
}
```
With this predicate-formatter, we can use
```
EXPECT_PRED_FORMAT2(AssertMutuallyPrime, b, c);
```
to generate the message
<pre>
b and c (4 and 10) are not mutually prime, as they have a common divisor 2.<br>
</pre>
As you may have realized, many of the assertions we introduced earlier are
special cases of `(EXPECT|ASSERT)_PRED_FORMAT*`. In fact, most of them are
indeed defined using `(EXPECT|ASSERT)_PRED_FORMAT*`.
_Availability_: Linux, Windows, Mac.
## Floating-Point Comparison ##
Comparing floating-point numbers is tricky. Due to round-off errors, it is
very unlikely that two floating-points will match exactly. Therefore,
`ASSERT_EQ` 's naive comparison usually doesn't work. And since floating-points
can have a wide value range, no single fixed error bound works. It's better to
compare by a fixed relative error bound, except for values close to 0 due to
the loss of precision there.
In general, for floating-point comparison to make sense, the user needs to
carefully choose the error bound. If they don't want or care to, comparing in
terms of Units in the Last Place (ULPs) is a good default, and Google Test
provides assertions to do this. Full details about ULPs are quite long; if you
want to learn more, see
[this article on float comparison](http://www.cygnus-software.com/papers/comparingfloats/comparingfloats.htm).
### Floating-Point Macros ###
| **Fatal assertion** | **Nonfatal assertion** | **Verifies** |
|:--------------------|:-----------------------|:-------------|
| `ASSERT_FLOAT_EQ(`_val1, val2_`);` | `EXPECT_FLOAT_EQ(`_val1, val2_`);` | the two `float` values are almost equal |
| `ASSERT_DOUBLE_EQ(`_val1, val2_`);` | `EXPECT_DOUBLE_EQ(`_val1, val2_`);` | the two `double` values are almost equal |
By "almost equal", we mean the two values are within 4 ULP's from each
other.
The following assertions allow you to choose the acceptable error bound:
| **Fatal assertion** | **Nonfatal assertion** | **Verifies** |
|:--------------------|:-----------------------|:-------------|
| `ASSERT_NEAR(`_val1, val2, abs\_error_`);` | `EXPECT_NEAR`_(val1, val2, abs\_error_`);` | the difference between _val1_ and _val2_ doesn't exceed the given absolute error |
_Availability_: Linux, Windows, Mac.
### Floating-Point Predicate-Format Functions ###
Some floating-point operations are useful, but not that often used. In order
to avoid an explosion of new macros, we provide them as predicate-format
functions that can be used in predicate assertion macros (e.g.
`EXPECT_PRED_FORMAT2`, etc).
```
EXPECT_PRED_FORMAT2(::testing::FloatLE, val1, val2);
EXPECT_PRED_FORMAT2(::testing::DoubleLE, val1, val2);
```
Verifies that _val1_ is less than, or almost equal to, _val2_. You can
replace `EXPECT_PRED_FORMAT2` in the above table with `ASSERT_PRED_FORMAT2`.
_Availability_: Linux, Windows, Mac.
## Windows HRESULT assertions ##
These assertions test for `HRESULT` success or failure.
| **Fatal assertion** | **Nonfatal assertion** | **Verifies** |
|:--------------------|:-----------------------|:-------------|
| `ASSERT_HRESULT_SUCCEEDED(`_expression_`);` | `EXPECT_HRESULT_SUCCEEDED(`_expression_`);` | _expression_ is a success `HRESULT` |
| `ASSERT_HRESULT_FAILED(`_expression_`);` | `EXPECT_HRESULT_FAILED(`_expression_`);` | _expression_ is a failure `HRESULT` |
The generated output contains the human-readable error message
associated with the `HRESULT` code returned by _expression_.
You might use them like this:
```
CComPtr shell;
ASSERT_HRESULT_SUCCEEDED(shell.CoCreateInstance(L"Shell.Application"));
CComVariant empty;
ASSERT_HRESULT_SUCCEEDED(shell->ShellExecute(CComBSTR(url), empty, empty, empty, empty));
```
_Availability_: Windows.
## Type Assertions ##
You can call the function
```
::testing::StaticAssertTypeEq<T1, T2>();
```
to assert that types `T1` and `T2` are the same. The function does
nothing if the assertion is satisfied. If the types are different,
the function call will fail to compile, and the compiler error message
will likely (depending on the compiler) show you the actual values of
`T1` and `T2`. This is mainly useful inside template code.
_Caveat:_ When used inside a member function of a class template or a
function template, `StaticAssertTypeEq<T1, T2>()` is effective _only if_
the function is instantiated. For example, given:
```
template <typename T> class Foo {
public:
void Bar() { ::testing::StaticAssertTypeEq<int, T>(); }
};
```
the code:
```
void Test1() { Foo<bool> foo; }
```
will _not_ generate a compiler error, as `Foo<bool>::Bar()` is never
actually instantiated. Instead, you need:
```
void Test2() { Foo<bool> foo; foo.Bar(); }
```
to cause a compiler error.
_Availability:_ Linux, Windows, Mac; since version 1.3.0.
## Assertion Placement ##
You can use assertions in any C++ function. In particular, it doesn't
have to be a method of the test fixture class. The one constraint is
that assertions that generate a fatal failure (`FAIL*` and `ASSERT_*`)
can only be used in void-returning functions. This is a consequence of
Google Test not using exceptions. By placing it in a non-void function
you'll get a confusing compile error like
`"error: void value not ignored as it ought to be"`.
If you need to use assertions in a function that returns non-void, one option
is to make the function return the value in an out parameter instead. For
example, you can rewrite `T2 Foo(T1 x)` to `void Foo(T1 x, T2* result)`. You
need to make sure that `*result` contains some sensible value even when the
function returns prematurely. As the function now returns `void`, you can use
any assertion inside of it.
If changing the function's type is not an option, you should just use
assertions that generate non-fatal failures, such as `ADD_FAILURE*` and
`EXPECT_*`.
_Note_: Constructors and destructors are not considered void-returning
functions, according to the C++ language specification, and so you may not use
fatal assertions in them. You'll get a compilation error if you try. A simple
workaround is to transfer the entire body of the constructor or destructor to a
private void-returning method. However, you should be aware that a fatal
assertion failure in a constructor does not terminate the current test, as your
intuition might suggest; it merely returns from the constructor early, possibly
leaving your object in a partially-constructed state. Likewise, a fatal
assertion failure in a destructor may leave your object in a
partially-destructed state. Use assertions carefully in these situations!
# Teaching Google Test How to Print Your Values #
When a test assertion such as `EXPECT_EQ` fails, Google Test prints the
argument values to help you debug. It does this using a
user-extensible value printer.
This printer knows how to print built-in C++ types, native arrays, STL
containers, and any type that supports the `<<` operator. For other
types, it prints the raw bytes in the value and hopes that you the
user can figure it out.
As mentioned earlier, the printer is _extensible_. That means
you can teach it to do a better job at printing your particular type
than to dump the bytes. To do that, define `<<` for your type:
```
#include <iostream>
namespace foo {
class Bar { ... }; // We want Google Test to be able to print instances of this.
// It's important that the << operator is defined in the SAME
// namespace that defines Bar. C++'s look-up rules rely on that.
::std::ostream& operator<<(::std::ostream& os, const Bar& bar) {
return os << bar.DebugString(); // whatever needed to print bar to os
}
} // namespace foo
```
Sometimes, this might not be an option: your team may consider it bad
style to have a `<<` operator for `Bar`, or `Bar` may already have a
`<<` operator that doesn't do what you want (and you cannot change
it). If so, you can instead define a `PrintTo()` function like this:
```
#include <iostream>
namespace foo {
class Bar { ... };
// It's important that PrintTo() is defined in the SAME
// namespace that defines Bar. C++'s look-up rules rely on that.
void PrintTo(const Bar& bar, ::std::ostream* os) {
*os << bar.DebugString(); // whatever needed to print bar to os
}
} // namespace foo
```
If you have defined both `<<` and `PrintTo()`, the latter will be used
when Google Test is concerned. This allows you to customize how the value
appears in Google Test's output without affecting code that relies on the
behavior of its `<<` operator.
If you want to print a value `x` using Google Test's value printer
yourself, just call `::testing::PrintToString(`_x_`)`, which
returns an `std::string`:
```
vector<pair<Bar, int> > bar_ints = GetBarIntVector();
EXPECT_TRUE(IsCorrectBarIntVector(bar_ints))
<< "bar_ints = " << ::testing::PrintToString(bar_ints);
```
# Death Tests #
In many applications, there are assertions that can cause application failure
if a condition is not met. These sanity checks, which ensure that the program
is in a known good state, are there to fail at the earliest possible time after
some program state is corrupted. If the assertion checks the wrong condition,
then the program may proceed in an erroneous state, which could lead to memory
corruption, security holes, or worse. Hence it is vitally important to test
that such assertion statements work as expected.
Since these precondition checks cause the processes to die, we call such tests
_death tests_. More generally, any test that checks that a program terminates
(except by throwing an exception) in an expected fashion is also a death test.
Note that if a piece of code throws an exception, we don't consider it "death"
for the purpose of death tests, as the caller of the code could catch the exception
and avoid the crash. If you want to verify exceptions thrown by your code,
see [Exception Assertions](#exception-assertions).
If you want to test `EXPECT_*()/ASSERT_*()` failures in your test code, see [Catching Failures](#catching-failures).
## How to Write a Death Test ##
Google Test has the following macros to support death tests:
| **Fatal assertion** | **Nonfatal assertion** | **Verifies** |
|:--------------------|:-----------------------|:-------------|
| `ASSERT_DEATH(`_statement, regex_`);` | `EXPECT_DEATH(`_statement, regex_`);` | _statement_ crashes with the given error |
| `ASSERT_DEATH_IF_SUPPORTED(`_statement, regex_`);` | `EXPECT_DEATH_IF_SUPPORTED(`_statement, regex_`);` | if death tests are supported, verifies that _statement_ crashes with the given error; otherwise verifies nothing |
| `ASSERT_EXIT(`_statement, predicate, regex_`);` | `EXPECT_EXIT(`_statement, predicate, regex_`);` |_statement_ exits with the given error and its exit code matches _predicate_ |
where _statement_ is a statement that is expected to cause the process to
die, _predicate_ is a function or function object that evaluates an integer
exit status, and _regex_ is a regular expression that the stderr output of
_statement_ is expected to match. Note that _statement_ can be _any valid
statement_ (including _compound statement_) and doesn't have to be an
expression.
As usual, the `ASSERT` variants abort the current test function, while the
`EXPECT` variants do not.
**Note:** We use the word "crash" here to mean that the process
terminates with a _non-zero_ exit status code. There are two
possibilities: either the process has called `exit()` or `_exit()`
with a non-zero value, or it may be killed by a signal.
This means that if _statement_ terminates the process with a 0 exit
code, it is _not_ considered a crash by `EXPECT_DEATH`. Use
`EXPECT_EXIT` instead if this is the case, or if you want to restrict
the exit code more precisely.
A predicate here must accept an `int` and return a `bool`. The death test
succeeds only if the predicate returns `true`. Google Test defines a few
predicates that handle the most common cases:
```
::testing::ExitedWithCode(exit_code)
```
This expression is `true` if the program exited normally with the given exit
code.
```
::testing::KilledBySignal(signal_number) // Not available on Windows.
```
This expression is `true` if the program was killed by the given signal.
The `*_DEATH` macros are convenient wrappers for `*_EXIT` that use a predicate
that verifies the process' exit code is non-zero.
Note that a death test only cares about three things:
1. does _statement_ abort or exit the process?
1. (in the case of `ASSERT_EXIT` and `EXPECT_EXIT`) does the exit status satisfy _predicate_? Or (in the case of `ASSERT_DEATH` and `EXPECT_DEATH`) is the exit status non-zero? And
1. does the stderr output match _regex_?
In particular, if _statement_ generates an `ASSERT_*` or `EXPECT_*` failure, it will **not** cause the death test to fail, as Google Test assertions don't abort the process.
To write a death test, simply use one of the above macros inside your test
function. For example,
```
TEST(MyDeathTest, Foo) {
// This death test uses a compound statement.
ASSERT_DEATH({ int n = 5; Foo(&n); }, "Error on line .* of Foo()");
}
TEST(MyDeathTest, NormalExit) {
EXPECT_EXIT(NormalExit(), ::testing::ExitedWithCode(0), "Success");
}
TEST(MyDeathTest, KillMyself) {
EXPECT_EXIT(KillMyself(), ::testing::KilledBySignal(SIGKILL), "Sending myself unblockable signal");
}
```
verifies that:
* calling `Foo(5)` causes the process to die with the given error message,
* calling `NormalExit()` causes the process to print `"Success"` to stderr and exit with exit code 0, and
* calling `KillMyself()` kills the process with signal `SIGKILL`.
The test function body may contain other assertions and statements as well, if
necessary.
_Important:_ We strongly recommend you to follow the convention of naming your
test case (not test) `*DeathTest` when it contains a death test, as
demonstrated in the above example. The `Death Tests And Threads` section below
explains why.
If a test fixture class is shared by normal tests and death tests, you
can use typedef to introduce an alias for the fixture class and avoid
duplicating its code:
```
class FooTest : public ::testing::Test { ... };
typedef FooTest FooDeathTest;
TEST_F(FooTest, DoesThis) {
// normal test
}
TEST_F(FooDeathTest, DoesThat) {
// death test
}
```
_Availability:_ Linux, Windows (requires MSVC 8.0 or above), Cygwin, and Mac (the latter three are supported since v1.3.0). `(ASSERT|EXPECT)_DEATH_IF_SUPPORTED` are new in v1.4.0.
## Regular Expression Syntax ##
On POSIX systems (e.g. Linux, Cygwin, and Mac), Google Test uses the
[POSIX extended regular expression](http://www.opengroup.org/onlinepubs/009695399/basedefs/xbd_chap09.html#tag_09_04)
syntax in death tests. To learn about this syntax, you may want to read this [Wikipedia entry](http://en.wikipedia.org/wiki/Regular_expression#POSIX_Extended_Regular_Expressions).
On Windows, Google Test uses its own simple regular expression
implementation. It lacks many features you can find in POSIX extended
regular expressions. For example, we don't support union (`"x|y"`),
grouping (`"(xy)"`), brackets (`"[xy]"`), and repetition count
(`"x{5,7}"`), among others. Below is what we do support (Letter `A` denotes a
literal character, period (`.`), or a single `\\` escape sequence; `x`
and `y` denote regular expressions.):
| `c` | matches any literal character `c` |
|:----|:----------------------------------|
| `\\d` | matches any decimal digit |
| `\\D` | matches any character that's not a decimal digit |
| `\\f` | matches `\f` |
| `\\n` | matches `\n` |
| `\\r` | matches `\r` |
| `\\s` | matches any ASCII whitespace, including `\n` |
| `\\S` | matches any character that's not a whitespace |
| `\\t` | matches `\t` |
| `\\v` | matches `\v` |
| `\\w` | matches any letter, `_`, or decimal digit |
| `\\W` | matches any character that `\\w` doesn't match |
| `\\c` | matches any literal character `c`, which must be a punctuation |
| `\\.` | matches the `.` character |
| `.` | matches any single character except `\n` |
| `A?` | matches 0 or 1 occurrences of `A` |
| `A*` | matches 0 or many occurrences of `A` |
| `A+` | matches 1 or many occurrences of `A` |
| `^` | matches the beginning of a string (not that of each line) |
| `$` | matches the end of a string (not that of each line) |
| `xy` | matches `x` followed by `y` |
To help you determine which capability is available on your system,
Google Test defines macro `GTEST_USES_POSIX_RE=1` when it uses POSIX
extended regular expressions, or `GTEST_USES_SIMPLE_RE=1` when it uses
the simple version. If you want your death tests to work in both
cases, you can either `#if` on these macros or use the more limited
syntax only.
## How It Works ##
Under the hood, `ASSERT_EXIT()` spawns a new process and executes the
death test statement in that process. The details of of how precisely
that happens depend on the platform and the variable
`::testing::GTEST_FLAG(death_test_style)` (which is initialized from the
command-line flag `--gtest_death_test_style`).
* On POSIX systems, `fork()` (or `clone()` on Linux) is used to spawn the child, after which:
* If the variable's value is `"fast"`, the death test statement is immediately executed.
* If the variable's value is `"threadsafe"`, the child process re-executes the unit test binary just as it was originally invoked, but with some extra flags to cause just the single death test under consideration to be run.
* On Windows, the child is spawned using the `CreateProcess()` API, and re-executes the binary to cause just the single death test under consideration to be run - much like the `threadsafe` mode on POSIX.
Other values for the variable are illegal and will cause the death test to
fail. Currently, the flag's default value is `"fast"`. However, we reserve the
right to change it in the future. Therefore, your tests should not depend on
this.
In either case, the parent process waits for the child process to complete, and checks that
1. the child's exit status satisfies the predicate, and
1. the child's stderr matches the regular expression.
If the death test statement runs to completion without dying, the child
process will nonetheless terminate, and the assertion fails.
## Death Tests And Threads ##
The reason for the two death test styles has to do with thread safety. Due to
well-known problems with forking in the presence of threads, death tests should
be run in a single-threaded context. Sometimes, however, it isn't feasible to
arrange that kind of environment. For example, statically-initialized modules
may start threads before main is ever reached. Once threads have been created,
it may be difficult or impossible to clean them up.
Google Test has three features intended to raise awareness of threading issues.
1. A warning is emitted if multiple threads are running when a death test is encountered.
1. Test cases with a name ending in "DeathTest" are run before all other tests.
1. It uses `clone()` instead of `fork()` to spawn the child process on Linux (`clone()` is not available on Cygwin and Mac), as `fork()` is more likely to cause the child to hang when the parent process has multiple threads.
It's perfectly fine to create threads inside a death test statement; they are
executed in a separate process and cannot affect the parent.
## Death Test Styles ##
The "threadsafe" death test style was introduced in order to help mitigate the
risks of testing in a possibly multithreaded environment. It trades increased
test execution time (potentially dramatically so) for improved thread safety.
We suggest using the faster, default "fast" style unless your test has specific
problems with it.
You can choose a particular style of death tests by setting the flag
programmatically:
```
::testing::FLAGS_gtest_death_test_style = "threadsafe";
```
You can do this in `main()` to set the style for all death tests in the
binary, or in individual tests. Recall that flags are saved before running each
test and restored afterwards, so you need not do that yourself. For example:
```
TEST(MyDeathTest, TestOne) {
::testing::FLAGS_gtest_death_test_style = "threadsafe";
// This test is run in the "threadsafe" style:
ASSERT_DEATH(ThisShouldDie(), "");
}
TEST(MyDeathTest, TestTwo) {
// This test is run in the "fast" style:
ASSERT_DEATH(ThisShouldDie(), "");
}
int main(int argc, char** argv) {
::testing::InitGoogleTest(&argc, argv);
::testing::FLAGS_gtest_death_test_style = "fast";
return RUN_ALL_TESTS();
}
```
## Caveats ##
The _statement_ argument of `ASSERT_EXIT()` can be any valid C++ statement.
If it leaves the current function via a `return` statement or by throwing an exception,
the death test is considered to have failed. Some Google Test macros may return
from the current function (e.g. `ASSERT_TRUE()`), so be sure to avoid them in _statement_.
Since _statement_ runs in the child process, any in-memory side effect (e.g.
modifying a variable, releasing memory, etc) it causes will _not_ be observable
in the parent process. In particular, if you release memory in a death test,
your program will fail the heap check as the parent process will never see the
memory reclaimed. To solve this problem, you can
1. try not to free memory in a death test;
1. free the memory again in the parent process; or
1. do not use the heap checker in your program.
Due to an implementation detail, you cannot place multiple death test
assertions on the same line; otherwise, compilation will fail with an unobvious
error message.
Despite the improved thread safety afforded by the "threadsafe" style of death
test, thread problems such as deadlock are still possible in the presence of
handlers registered with `pthread_atfork(3)`.
# Using Assertions in Sub-routines #
## Adding Traces to Assertions ##
If a test sub-routine is called from several places, when an assertion
inside it fails, it can be hard to tell which invocation of the
sub-routine the failure is from. You can alleviate this problem using
extra logging or custom failure messages, but that usually clutters up
your tests. A better solution is to use the `SCOPED_TRACE` macro:
| `SCOPED_TRACE(`_message_`);` |
|:-----------------------------|
where _message_ can be anything streamable to `std::ostream`. This
macro will cause the current file name, line number, and the given
message to be added in every failure message. The effect will be
undone when the control leaves the current lexical scope.
For example,
```
10: void Sub1(int n) {
11: EXPECT_EQ(1, Bar(n));
12: EXPECT_EQ(2, Bar(n + 1));
13: }
14:
15: TEST(FooTest, Bar) {
16: {
17: SCOPED_TRACE("A"); // This trace point will be included in
18: // every failure in this scope.
19: Sub1(1);
20: }
21: // Now it won't.
22: Sub1(9);
23: }
```
could result in messages like these:
```
path/to/foo_test.cc:11: Failure
Value of: Bar(n)
Expected: 1
Actual: 2
Trace:
path/to/foo_test.cc:17: A
path/to/foo_test.cc:12: Failure
Value of: Bar(n + 1)
Expected: 2
Actual: 3
```
Without the trace, it would've been difficult to know which invocation
of `Sub1()` the two failures come from respectively. (You could add an
extra message to each assertion in `Sub1()` to indicate the value of
`n`, but that's tedious.)
Some tips on using `SCOPED_TRACE`:
1. With a suitable message, it's often enough to use `SCOPED_TRACE` at the beginning of a sub-routine, instead of at each call site.
1. When calling sub-routines inside a loop, make the loop iterator part of the message in `SCOPED_TRACE` such that you can know which iteration the failure is from.
1. Sometimes the line number of the trace point is enough for identifying the particular invocation of a sub-routine. In this case, you don't have to choose a unique message for `SCOPED_TRACE`. You can simply use `""`.
1. You can use `SCOPED_TRACE` in an inner scope when there is one in the outer scope. In this case, all active trace points will be included in the failure messages, in reverse order they are encountered.
1. The trace dump is clickable in Emacs' compilation buffer - hit return on a line number and you'll be taken to that line in the source file!
_Availability:_ Linux, Windows, Mac.
## Propagating Fatal Failures ##
A common pitfall when using `ASSERT_*` and `FAIL*` is not understanding that
when they fail they only abort the _current function_, not the entire test. For
example, the following test will segfault:
```
void Subroutine() {
// Generates a fatal failure and aborts the current function.
ASSERT_EQ(1, 2);
// The following won't be executed.
...
}
TEST(FooTest, Bar) {
Subroutine();
// The intended behavior is for the fatal failure
// in Subroutine() to abort the entire test.
// The actual behavior: the function goes on after Subroutine() returns.
int* p = NULL;
*p = 3; // Segfault!
}
```
Since we don't use exceptions, it is technically impossible to
implement the intended behavior here. To alleviate this, Google Test
provides two solutions. You could use either the
`(ASSERT|EXPECT)_NO_FATAL_FAILURE` assertions or the
`HasFatalFailure()` function. They are described in the following two
subsections.
### Asserting on Subroutines ###
As shown above, if your test calls a subroutine that has an `ASSERT_*`
failure in it, the test will continue after the subroutine
returns. This may not be what you want.
Often people want fatal failures to propagate like exceptions. For
that Google Test offers the following macros:
| **Fatal assertion** | **Nonfatal assertion** | **Verifies** |
|:--------------------|:-----------------------|:-------------|
| `ASSERT_NO_FATAL_FAILURE(`_statement_`);` | `EXPECT_NO_FATAL_FAILURE(`_statement_`);` | _statement_ doesn't generate any new fatal failures in the current thread. |
Only failures in the thread that executes the assertion are checked to
determine the result of this type of assertions. If _statement_
creates new threads, failures in these threads are ignored.
Examples:
```
ASSERT_NO_FATAL_FAILURE(Foo());
int i;
EXPECT_NO_FATAL_FAILURE({
i = Bar();
});
```
_Availability:_ Linux, Windows, Mac. Assertions from multiple threads
are currently not supported.
### Checking for Failures in the Current Test ###
`HasFatalFailure()` in the `::testing::Test` class returns `true` if an
assertion in the current test has suffered a fatal failure. This
allows functions to catch fatal failures in a sub-routine and return
early.
```
class Test {
public:
...
static bool HasFatalFailure();
};
```
The typical usage, which basically simulates the behavior of a thrown
exception, is:
```
TEST(FooTest, Bar) {
Subroutine();
// Aborts if Subroutine() had a fatal failure.
if (HasFatalFailure())
return;
// The following won't be executed.
...
}
```
If `HasFatalFailure()` is used outside of `TEST()` , `TEST_F()` , or a test
fixture, you must add the `::testing::Test::` prefix, as in:
```
if (::testing::Test::HasFatalFailure())
return;
```
Similarly, `HasNonfatalFailure()` returns `true` if the current test
has at least one non-fatal failure, and `HasFailure()` returns `true`
if the current test has at least one failure of either kind.
_Availability:_ Linux, Windows, Mac. `HasNonfatalFailure()` and
`HasFailure()` are available since version 1.4.0.
# Logging Additional Information #
In your test code, you can call `RecordProperty("key", value)` to log
additional information, where `value` can be either a string or an `int`. The _last_ value recorded for a key will be emitted to the XML output
if you specify one. For example, the test
```
TEST_F(WidgetUsageTest, MinAndMaxWidgets) {
RecordProperty("MaximumWidgets", ComputeMaxUsage());
RecordProperty("MinimumWidgets", ComputeMinUsage());
}
```
will output XML like this:
```
...
<testcase name="MinAndMaxWidgets" status="run" time="6" classname="WidgetUsageTest"
MaximumWidgets="12"
MinimumWidgets="9" />
...
```
_Note_:
* `RecordProperty()` is a static member of the `Test` class. Therefore it needs to be prefixed with `::testing::Test::` if used outside of the `TEST` body and the test fixture class.
* `key` must be a valid XML attribute name, and cannot conflict with the ones already used by Google Test (`name`, `status`, `time`, `classname`, `type_param`, and `value_param`).
* Calling `RecordProperty()` outside of the lifespan of a test is allowed. If it's called outside of a test but between a test case's `SetUpTestCase()` and `TearDownTestCase()` methods, it will be attributed to the XML element for the test case. If it's called outside of all test cases (e.g. in a test environment), it will be attributed to the top-level XML element.
_Availability_: Linux, Windows, Mac.
# Sharing Resources Between Tests in the Same Test Case #
Google Test creates a new test fixture object for each test in order to make
tests independent and easier to debug. However, sometimes tests use resources
that are expensive to set up, making the one-copy-per-test model prohibitively
expensive.
If the tests don't change the resource, there's no harm in them sharing a
single resource copy. So, in addition to per-test set-up/tear-down, Google Test
also supports per-test-case set-up/tear-down. To use it:
1. In your test fixture class (say `FooTest` ), define as `static` some member variables to hold the shared resources.
1. In the same test fixture class, define a `static void SetUpTestCase()` function (remember not to spell it as **`SetupTestCase`** with a small `u`!) to set up the shared resources and a `static void TearDownTestCase()` function to tear them down.
That's it! Google Test automatically calls `SetUpTestCase()` before running the
_first test_ in the `FooTest` test case (i.e. before creating the first
`FooTest` object), and calls `TearDownTestCase()` after running the _last test_
in it (i.e. after deleting the last `FooTest` object). In between, the tests
can use the shared resources.
Remember that the test order is undefined, so your code can't depend on a test
preceding or following another. Also, the tests must either not modify the
state of any shared resource, or, if they do modify the state, they must
restore the state to its original value before passing control to the next
test.
Here's an example of per-test-case set-up and tear-down:
```
class FooTest : public ::testing::Test {
protected:
// Per-test-case set-up.
// Called before the first test in this test case.
// Can be omitted if not needed.
static void SetUpTestCase() {
shared_resource_ = new ...;
}
// Per-test-case tear-down.
// Called after the last test in this test case.
// Can be omitted if not needed.
static void TearDownTestCase() {
delete shared_resource_;
shared_resource_ = NULL;
}
// You can define per-test set-up and tear-down logic as usual.
virtual void SetUp() { ... }
virtual void TearDown() { ... }
// Some expensive resource shared by all tests.
static T* shared_resource_;
};
T* FooTest::shared_resource_ = NULL;
TEST_F(FooTest, Test1) {
... you can refer to shared_resource here ...
}
TEST_F(FooTest, Test2) {
... you can refer to shared_resource here ...
}
```
_Availability:_ Linux, Windows, Mac.
# Global Set-Up and Tear-Down #
Just as you can do set-up and tear-down at the test level and the test case
level, you can also do it at the test program level. Here's how.
First, you subclass the `::testing::Environment` class to define a test
environment, which knows how to set-up and tear-down:
```
class Environment {
public:
virtual ~Environment() {}
// Override this to define how to set up the environment.
virtual void SetUp() {}
// Override this to define how to tear down the environment.
virtual void TearDown() {}
};
```
Then, you register an instance of your environment class with Google Test by
calling the `::testing::AddGlobalTestEnvironment()` function:
```
Environment* AddGlobalTestEnvironment(Environment* env);
```
Now, when `RUN_ALL_TESTS()` is called, it first calls the `SetUp()` method of
the environment object, then runs the tests if there was no fatal failures, and
finally calls `TearDown()` of the environment object.
It's OK to register multiple environment objects. In this case, their `SetUp()`
will be called in the order they are registered, and their `TearDown()` will be
called in the reverse order.
Note that Google Test takes ownership of the registered environment objects.
Therefore **do not delete them** by yourself.
You should call `AddGlobalTestEnvironment()` before `RUN_ALL_TESTS()` is
called, probably in `main()`. If you use `gtest_main`, you need to call
this before `main()` starts for it to take effect. One way to do this is to
define a global variable like this:
```
::testing::Environment* const foo_env = ::testing::AddGlobalTestEnvironment(new FooEnvironment);
```
However, we strongly recommend you to write your own `main()` and call
`AddGlobalTestEnvironment()` there, as relying on initialization of global
variables makes the code harder to read and may cause problems when you
register multiple environments from different translation units and the
environments have dependencies among them (remember that the compiler doesn't
guarantee the order in which global variables from different translation units
are initialized).
_Availability:_ Linux, Windows, Mac.
# Value Parameterized Tests #
_Value-parameterized tests_ allow you to test your code with different
parameters without writing multiple copies of the same test.
Suppose you write a test for your code and then realize that your code is affected by a presence of a Boolean command line flag.
```
TEST(MyCodeTest, TestFoo) {
// A code to test foo().
}
```
Usually people factor their test code into a function with a Boolean parameter in such situations. The function sets the flag, then executes the testing code.
```
void TestFooHelper(bool flag_value) {
flag = flag_value;
// A code to test foo().
}
TEST(MyCodeTest, TestFoo) {
TestFooHelper(false);
TestFooHelper(true);
}
```
But this setup has serious drawbacks. First, when a test assertion fails in your tests, it becomes unclear what value of the parameter caused it to fail. You can stream a clarifying message into your `EXPECT`/`ASSERT` statements, but it you'll have to do it with all of them. Second, you have to add one such helper function per test. What if you have ten tests? Twenty? A hundred?
Value-parameterized tests will let you write your test only once and then easily instantiate and run it with an arbitrary number of parameter values.
Here are some other situations when value-parameterized tests come handy:
* You want to test different implementations of an OO interface.
* You want to test your code over various inputs (a.k.a. data-driven testing). This feature is easy to abuse, so please exercise your good sense when doing it!
## How to Write Value-Parameterized Tests ##
To write value-parameterized tests, first you should define a fixture
class. It must be derived from both `::testing::Test` and
`::testing::WithParamInterface<T>` (the latter is a pure interface),
where `T` is the type of your parameter values. For convenience, you
can just derive the fixture class from `::testing::TestWithParam<T>`,
which itself is derived from both `::testing::Test` and
`::testing::WithParamInterface<T>`. `T` can be any copyable type. If
it's a raw pointer, you are responsible for managing the lifespan of
the pointed values.
```
class FooTest : public ::testing::TestWithParam<const char*> {
// You can implement all the usual fixture class members here.
// To access the test parameter, call GetParam() from class
// TestWithParam<T>.
};
// Or, when you want to add parameters to a pre-existing fixture class:
class BaseTest : public ::testing::Test {
...
};
class BarTest : public BaseTest,
public ::testing::WithParamInterface<const char*> {
...
};
```
Then, use the `TEST_P` macro to define as many test patterns using
this fixture as you want. The `_P` suffix is for "parameterized" or
"pattern", whichever you prefer to think.
```
TEST_P(FooTest, DoesBlah) {
// Inside a test, access the test parameter with the GetParam() method
// of the TestWithParam<T> class:
EXPECT_TRUE(foo.Blah(GetParam()));
...
}
TEST_P(FooTest, HasBlahBlah) {
...
}
```
Finally, you can use `INSTANTIATE_TEST_CASE_P` to instantiate the test
case with any set of parameters you want. Google Test defines a number of
functions for generating test parameters. They return what we call
(surprise!) _parameter generators_. Here is a summary of them,
which are all in the `testing` namespace:
| `Range(begin, end[, step])` | Yields values `{begin, begin+step, begin+step+step, ...}`. The values do not include `end`. `step` defaults to 1. |
|:----------------------------|:------------------------------------------------------------------------------------------------------------------|
| `Values(v1, v2, ..., vN)` | Yields values `{v1, v2, ..., vN}`. |
| `ValuesIn(container)` and `ValuesIn(begin, end)` | Yields values from a C-style array, an STL-style container, or an iterator range `[begin, end)`. `container`, `begin`, and `end` can be expressions whose values are determined at run time. |
| `Bool()` | Yields sequence `{false, true}`. |
| `Combine(g1, g2, ..., gN)` | Yields all combinations (the Cartesian product for the math savvy) of the values generated by the `N` generators. This is only available if your system provides the `<tr1/tuple>` header. If you are sure your system does, and Google Test disagrees, you can override it by defining `GTEST_HAS_TR1_TUPLE=1`. See comments in [include/gtest/internal/gtest-port.h](../include/gtest/internal/gtest-port.h) for more information. |
For more details, see the comments at the definitions of these functions in the [source code](../include/gtest/gtest-param-test.h).
The following statement will instantiate tests from the `FooTest` test case
each with parameter values `"meeny"`, `"miny"`, and `"moe"`.
```
INSTANTIATE_TEST_CASE_P(InstantiationName,
FooTest,
::testing::Values("meeny", "miny", "moe"));
```
To distinguish different instances of the pattern (yes, you can
instantiate it more than once), the first argument to
`INSTANTIATE_TEST_CASE_P` is a prefix that will be added to the actual
test case name. Remember to pick unique prefixes for different
instantiations. The tests from the instantiation above will have these
names:
* `InstantiationName/FooTest.DoesBlah/0` for `"meeny"`
* `InstantiationName/FooTest.DoesBlah/1` for `"miny"`
* `InstantiationName/FooTest.DoesBlah/2` for `"moe"`
* `InstantiationName/FooTest.HasBlahBlah/0` for `"meeny"`
* `InstantiationName/FooTest.HasBlahBlah/1` for `"miny"`
* `InstantiationName/FooTest.HasBlahBlah/2` for `"moe"`
You can use these names in [--gtest\_filter](#running-a-subset-of-the-tests).
This statement will instantiate all tests from `FooTest` again, each
with parameter values `"cat"` and `"dog"`:
```
const char* pets[] = {"cat", "dog"};
INSTANTIATE_TEST_CASE_P(AnotherInstantiationName, FooTest,
::testing::ValuesIn(pets));
```
The tests from the instantiation above will have these names:
* `AnotherInstantiationName/FooTest.DoesBlah/0` for `"cat"`
* `AnotherInstantiationName/FooTest.DoesBlah/1` for `"dog"`
* `AnotherInstantiationName/FooTest.HasBlahBlah/0` for `"cat"`
* `AnotherInstantiationName/FooTest.HasBlahBlah/1` for `"dog"`
Please note that `INSTANTIATE_TEST_CASE_P` will instantiate _all_
tests in the given test case, whether their definitions come before or
_after_ the `INSTANTIATE_TEST_CASE_P` statement.
You can see
[these](../samples/sample7_unittest.cc)
[files](../samples/sample8_unittest.cc) for more examples.
_Availability_: Linux, Windows (requires MSVC 8.0 or above), Mac; since version 1.2.0.
## Creating Value-Parameterized Abstract Tests ##
In the above, we define and instantiate `FooTest` in the same source
file. Sometimes you may want to define value-parameterized tests in a
library and let other people instantiate them later. This pattern is
known as <i>abstract tests</i>. As an example of its application, when you
are designing an interface you can write a standard suite of abstract
tests (perhaps using a factory function as the test parameter) that
all implementations of the interface are expected to pass. When
someone implements the interface, he can instantiate your suite to get
all the interface-conformance tests for free.
To define abstract tests, you should organize your code like this:
1. Put the definition of the parameterized test fixture class (e.g. `FooTest`) in a header file, say `foo_param_test.h`. Think of this as _declaring_ your abstract tests.
1. Put the `TEST_P` definitions in `foo_param_test.cc`, which includes `foo_param_test.h`. Think of this as _implementing_ your abstract tests.
Once they are defined, you can instantiate them by including
`foo_param_test.h`, invoking `INSTANTIATE_TEST_CASE_P()`, and linking
with `foo_param_test.cc`. You can instantiate the same abstract test
case multiple times, possibly in different source files.
# Typed Tests #
Suppose you have multiple implementations of the same interface and
want to make sure that all of them satisfy some common requirements.
Or, you may have defined several types that are supposed to conform to
the same "concept" and you want to verify it. In both cases, you want
the same test logic repeated for different types.
While you can write one `TEST` or `TEST_F` for each type you want to
test (and you may even factor the test logic into a function template
that you invoke from the `TEST`), it's tedious and doesn't scale:
if you want _m_ tests over _n_ types, you'll end up writing _m\*n_
`TEST`s.
_Typed tests_ allow you to repeat the same test logic over a list of
types. You only need to write the test logic once, although you must
know the type list when writing typed tests. Here's how you do it:
First, define a fixture class template. It should be parameterized
by a type. Remember to derive it from `::testing::Test`:
```
template <typename T>
class FooTest : public ::testing::Test {
public:
...
typedef std::list<T> List;
static T shared_;
T value_;
};
```
Next, associate a list of types with the test case, which will be
repeated for each type in the list:
```
typedef ::testing::Types<char, int, unsigned int> MyTypes;
TYPED_TEST_CASE(FooTest, MyTypes);
```
The `typedef` is necessary for the `TYPED_TEST_CASE` macro to parse
correctly. Otherwise the compiler will think that each comma in the
type list introduces a new macro argument.
Then, use `TYPED_TEST()` instead of `TEST_F()` to define a typed test
for this test case. You can repeat this as many times as you want:
```
TYPED_TEST(FooTest, DoesBlah) {
// Inside a test, refer to the special name TypeParam to get the type
// parameter. Since we are inside a derived class template, C++ requires
// us to visit the members of FooTest via 'this'.
TypeParam n = this->value_;
// To visit static members of the fixture, add the 'TestFixture::'
// prefix.
n += TestFixture::shared_;
// To refer to typedefs in the fixture, add the 'typename TestFixture::'
// prefix. The 'typename' is required to satisfy the compiler.
typename TestFixture::List values;
values.push_back(n);
...
}
TYPED_TEST(FooTest, HasPropertyA) { ... }
```
You can see `samples/sample6_unittest.cc` for a complete example.
_Availability:_ Linux, Windows (requires MSVC 8.0 or above), Mac;
since version 1.1.0.
# Type-Parameterized Tests #
_Type-parameterized tests_ are like typed tests, except that they
don't require you to know the list of types ahead of time. Instead,
you can define the test logic first and instantiate it with different
type lists later. You can even instantiate it more than once in the
same program.
If you are designing an interface or concept, you can define a suite
of type-parameterized tests to verify properties that any valid
implementation of the interface/concept should have. Then, the author
of each implementation can just instantiate the test suite with his
type to verify that it conforms to the requirements, without having to
write similar tests repeatedly. Here's an example:
First, define a fixture class template, as we did with typed tests:
```
template <typename T>
class FooTest : public ::testing::Test {
...
};
```
Next, declare that you will define a type-parameterized test case:
```
TYPED_TEST_CASE_P(FooTest);
```
The `_P` suffix is for "parameterized" or "pattern", whichever you
prefer to think.
Then, use `TYPED_TEST_P()` to define a type-parameterized test. You
can repeat this as many times as you want:
```
TYPED_TEST_P(FooTest, DoesBlah) {
// Inside a test, refer to TypeParam to get the type parameter.
TypeParam n = 0;
...
}
TYPED_TEST_P(FooTest, HasPropertyA) { ... }
```
Now the tricky part: you need to register all test patterns using the
`REGISTER_TYPED_TEST_CASE_P` macro before you can instantiate them.
The first argument of the macro is the test case name; the rest are
the names of the tests in this test case:
```
REGISTER_TYPED_TEST_CASE_P(FooTest,
DoesBlah, HasPropertyA);
```
Finally, you are free to instantiate the pattern with the types you
want. If you put the above code in a header file, you can `#include`
it in multiple C++ source files and instantiate it multiple times.
```
typedef ::testing::Types<char, int, unsigned int> MyTypes;
INSTANTIATE_TYPED_TEST_CASE_P(My, FooTest, MyTypes);
```
To distinguish different instances of the pattern, the first argument
to the `INSTANTIATE_TYPED_TEST_CASE_P` macro is a prefix that will be
added to the actual test case name. Remember to pick unique prefixes
for different instances.
In the special case where the type list contains only one type, you
can write that type directly without `::testing::Types<...>`, like this:
```
INSTANTIATE_TYPED_TEST_CASE_P(My, FooTest, int);
```
You can see `samples/sample6_unittest.cc` for a complete example.
_Availability:_ Linux, Windows (requires MSVC 8.0 or above), Mac;
since version 1.1.0.
# Testing Private Code #
If you change your software's internal implementation, your tests should not
break as long as the change is not observable by users. Therefore, per the
_black-box testing principle_, most of the time you should test your code
through its public interfaces.
If you still find yourself needing to test internal implementation code,
consider if there's a better design that wouldn't require you to do so. If you
absolutely have to test non-public interface code though, you can. There are
two cases to consider:
* Static functions (_not_ the same as static member functions!) or unnamed namespaces, and
* Private or protected class members
## Static Functions ##
Both static functions and definitions/declarations in an unnamed namespace are
only visible within the same translation unit. To test them, you can `#include`
the entire `.cc` file being tested in your `*_test.cc` file. (`#include`ing `.cc`
files is not a good way to reuse code - you should not do this in production
code!)
However, a better approach is to move the private code into the
`foo::internal` namespace, where `foo` is the namespace your project normally
uses, and put the private declarations in a `*-internal.h` file. Your
production `.cc` files and your tests are allowed to include this internal
header, but your clients are not. This way, you can fully test your internal
implementation without leaking it to your clients.
## Private Class Members ##
Private class members are only accessible from within the class or by friends.
To access a class' private members, you can declare your test fixture as a
friend to the class and define accessors in your fixture. Tests using the
fixture can then access the private members of your production class via the
accessors in the fixture. Note that even though your fixture is a friend to
your production class, your tests are not automatically friends to it, as they
are technically defined in sub-classes of the fixture.
Another way to test private members is to refactor them into an implementation
class, which is then declared in a `*-internal.h` file. Your clients aren't
allowed to include this header but your tests can. Such is called the Pimpl
(Private Implementation) idiom.
Or, you can declare an individual test as a friend of your class by adding this
line in the class body:
```
FRIEND_TEST(TestCaseName, TestName);
```
For example,
```
// foo.h
#include "gtest/gtest_prod.h"
// Defines FRIEND_TEST.
class Foo {
...
private:
FRIEND_TEST(FooTest, BarReturnsZeroOnNull);
int Bar(void* x);
};
// foo_test.cc
...
TEST(FooTest, BarReturnsZeroOnNull) {
Foo foo;
EXPECT_EQ(0, foo.Bar(NULL));
// Uses Foo's private member Bar().
}
```
Pay special attention when your class is defined in a namespace, as you should
define your test fixtures and tests in the same namespace if you want them to
be friends of your class. For example, if the code to be tested looks like:
```
namespace my_namespace {
class Foo {
friend class FooTest;
FRIEND_TEST(FooTest, Bar);
FRIEND_TEST(FooTest, Baz);
...
definition of the class Foo
...
};
} // namespace my_namespace
```
Your test code should be something like:
```
namespace my_namespace {
class FooTest : public ::testing::Test {
protected:
...
};
TEST_F(FooTest, Bar) { ... }
TEST_F(FooTest, Baz) { ... }
} // namespace my_namespace
```
# Catching Failures #
If you are building a testing utility on top of Google Test, you'll
want to test your utility. What framework would you use to test it?
Google Test, of course.
The challenge is to verify that your testing utility reports failures
correctly. In frameworks that report a failure by throwing an
exception, you could catch the exception and assert on it. But Google
Test doesn't use exceptions, so how do we test that a piece of code
generates an expected failure?
`"gtest/gtest-spi.h"` contains some constructs to do this. After
`#include`ing this header, you can use
| `EXPECT_FATAL_FAILURE(`_statement, substring_`);` |
|:--------------------------------------------------|
to assert that _statement_ generates a fatal (e.g. `ASSERT_*`) failure
whose message contains the given _substring_, or use
| `EXPECT_NONFATAL_FAILURE(`_statement, substring_`);` |
|:-----------------------------------------------------|
if you are expecting a non-fatal (e.g. `EXPECT_*`) failure.
For technical reasons, there are some caveats:
1. You cannot stream a failure message to either macro.
1. _statement_ in `EXPECT_FATAL_FAILURE()` cannot reference local non-static variables or non-static members of `this` object.
1. _statement_ in `EXPECT_FATAL_FAILURE()` cannot return a value.
_Note:_ Google Test is designed with threads in mind. Once the
synchronization primitives in `"gtest/internal/gtest-port.h"` have
been implemented, Google Test will become thread-safe, meaning that
you can then use assertions in multiple threads concurrently. Before
that, however, Google Test only supports single-threaded usage. Once
thread-safe, `EXPECT_FATAL_FAILURE()` and `EXPECT_NONFATAL_FAILURE()`
will capture failures in the current thread only. If _statement_
creates new threads, failures in these threads will be ignored. If
you want to capture failures from all threads instead, you should use
the following macros:
| `EXPECT_FATAL_FAILURE_ON_ALL_THREADS(`_statement, substring_`);` |
|:-----------------------------------------------------------------|
| `EXPECT_NONFATAL_FAILURE_ON_ALL_THREADS(`_statement, substring_`);` |
# Getting the Current Test's Name #
Sometimes a function may need to know the name of the currently running test.
For example, you may be using the `SetUp()` method of your test fixture to set
the golden file name based on which test is running. The `::testing::TestInfo`
class has this information:
```
namespace testing {
class TestInfo {
public:
// Returns the test case name and the test name, respectively.
//
// Do NOT delete or free the return value - it's managed by the
// TestInfo class.
const char* test_case_name() const;
const char* name() const;
};
} // namespace testing
```
> To obtain a `TestInfo` object for the currently running test, call
`current_test_info()` on the `UnitTest` singleton object:
```
// Gets information about the currently running test.
// Do NOT delete the returned object - it's managed by the UnitTest class.
const ::testing::TestInfo* const test_info =
::testing::UnitTest::GetInstance()->current_test_info();
printf("We are in test %s of test case %s.\n",
test_info->name(), test_info->test_case_name());
```
`current_test_info()` returns a null pointer if no test is running. In
particular, you cannot find the test case name in `TestCaseSetUp()`,
`TestCaseTearDown()` (where you know the test case name implicitly), or
functions called from them.
_Availability:_ Linux, Windows, Mac.
# Extending Google Test by Handling Test Events #
Google Test provides an <b>event listener API</b> to let you receive
notifications about the progress of a test program and test
failures. The events you can listen to include the start and end of
the test program, a test case, or a test method, among others. You may
use this API to augment or replace the standard console output,
replace the XML output, or provide a completely different form of
output, such as a GUI or a database. You can also use test events as
checkpoints to implement a resource leak checker, for example.
_Availability:_ Linux, Windows, Mac; since v1.4.0.
## Defining Event Listeners ##
To define a event listener, you subclass either
[testing::TestEventListener](../include/gtest/gtest.h#L991)
or [testing::EmptyTestEventListener](../include/gtest/gtest.h#L1044).
The former is an (abstract) interface, where <i>each pure virtual method<br>
can be overridden to handle a test event</i> (For example, when a test
starts, the `OnTestStart()` method will be called.). The latter provides
an empty implementation of all methods in the interface, such that a
subclass only needs to override the methods it cares about.
When an event is fired, its context is passed to the handler function
as an argument. The following argument types are used:
* [UnitTest](../include/gtest/gtest.h#L1151) reflects the state of the entire test program,
* [TestCase](../include/gtest/gtest.h#L778) has information about a test case, which can contain one or more tests,
* [TestInfo](../include/gtest/gtest.h#L644) contains the state of a test, and
* [TestPartResult](../include/gtest/gtest-test-part.h#L47) represents the result of a test assertion.
An event handler function can examine the argument it receives to find
out interesting information about the event and the test program's
state. Here's an example:
```
class MinimalistPrinter : public ::testing::EmptyTestEventListener {
// Called before a test starts.
virtual void OnTestStart(const ::testing::TestInfo& test_info) {
printf("*** Test %s.%s starting.\n",
test_info.test_case_name(), test_info.name());
}
// Called after a failed assertion or a SUCCEED() invocation.
virtual void OnTestPartResult(
const ::testing::TestPartResult& test_part_result) {
printf("%s in %s:%d\n%s\n",
test_part_result.failed() ? "*** Failure" : "Success",
test_part_result.file_name(),
test_part_result.line_number(),
test_part_result.summary());
}
// Called after a test ends.
virtual void OnTestEnd(const ::testing::TestInfo& test_info) {
printf("*** Test %s.%s ending.\n",
test_info.test_case_name(), test_info.name());
}
};
```
## Using Event Listeners ##
To use the event listener you have defined, add an instance of it to
the Google Test event listener list (represented by class
[TestEventListeners](../include/gtest/gtest.h#L1064)
- note the "s" at the end of the name) in your
`main()` function, before calling `RUN_ALL_TESTS()`:
```
int main(int argc, char** argv) {
::testing::InitGoogleTest(&argc, argv);
// Gets hold of the event listener list.
::testing::TestEventListeners& listeners =
::testing::UnitTest::GetInstance()->listeners();
// Adds a listener to the end. Google Test takes the ownership.
listeners.Append(new MinimalistPrinter);
return RUN_ALL_TESTS();
}
```
There's only one problem: the default test result printer is still in
effect, so its output will mingle with the output from your minimalist
printer. To suppress the default printer, just release it from the
event listener list and delete it. You can do so by adding one line:
```
...
delete listeners.Release(listeners.default_result_printer());
listeners.Append(new MinimalistPrinter);
return RUN_ALL_TESTS();
```
Now, sit back and enjoy a completely different output from your
tests. For more details, you can read this
[sample](../samples/sample9_unittest.cc).
You may append more than one listener to the list. When an `On*Start()`
or `OnTestPartResult()` event is fired, the listeners will receive it in
the order they appear in the list (since new listeners are added to
the end of the list, the default text printer and the default XML
generator will receive the event first). An `On*End()` event will be
received by the listeners in the _reverse_ order. This allows output by
listeners added later to be framed by output from listeners added
earlier.
## Generating Failures in Listeners ##
You may use failure-raising macros (`EXPECT_*()`, `ASSERT_*()`,
`FAIL()`, etc) when processing an event. There are some restrictions:
1. You cannot generate any failure in `OnTestPartResult()` (otherwise it will cause `OnTestPartResult()` to be called recursively).
1. A listener that handles `OnTestPartResult()` is not allowed to generate any failure.
When you add listeners to the listener list, you should put listeners
that handle `OnTestPartResult()` _before_ listeners that can generate
failures. This ensures that failures generated by the latter are
attributed to the right test by the former.
We have a sample of failure-raising listener
[here](../samples/sample10_unittest.cc).
# Running Test Programs: Advanced Options #
Google Test test programs are ordinary executables. Once built, you can run
them directly and affect their behavior via the following environment variables
and/or command line flags. For the flags to work, your programs must call
`::testing::InitGoogleTest()` before calling `RUN_ALL_TESTS()`.
To see a list of supported flags and their usage, please run your test
program with the `--help` flag. You can also use `-h`, `-?`, or `/?`
for short. This feature is added in version 1.3.0.
If an option is specified both by an environment variable and by a
flag, the latter takes precedence. Most of the options can also be
set/read in code: to access the value of command line flag
`--gtest_foo`, write `::testing::GTEST_FLAG(foo)`. A common pattern is
to set the value of a flag before calling `::testing::InitGoogleTest()`
to change the default value of the flag:
```
int main(int argc, char** argv) {
// Disables elapsed time by default.
::testing::GTEST_FLAG(print_time) = false;
// This allows the user to override the flag on the command line.
::testing::InitGoogleTest(&argc, argv);
return RUN_ALL_TESTS();
}
```
## Selecting Tests ##
This section shows various options for choosing which tests to run.
### Listing Test Names ###
Sometimes it is necessary to list the available tests in a program before
running them so that a filter may be applied if needed. Including the flag
`--gtest_list_tests` overrides all other flags and lists tests in the following
format:
```
TestCase1.
TestName1
TestName2
TestCase2.
TestName
```
None of the tests listed are actually run if the flag is provided. There is no
corresponding environment variable for this flag.
_Availability:_ Linux, Windows, Mac.
### Running a Subset of the Tests ###
By default, a Google Test program runs all tests the user has defined.
Sometimes, you want to run only a subset of the tests (e.g. for debugging or
quickly verifying a change). If you set the `GTEST_FILTER` environment variable
or the `--gtest_filter` flag to a filter string, Google Test will only run the
tests whose full names (in the form of `TestCaseName.TestName`) match the
filter.
The format of a filter is a '`:`'-separated list of wildcard patterns (called
the positive patterns) optionally followed by a '`-`' and another
'`:`'-separated pattern list (called the negative patterns). A test matches the
filter if and only if it matches any of the positive patterns but does not
match any of the negative patterns.
A pattern may contain `'*'` (matches any string) or `'?'` (matches any single
character). For convenience, the filter `'*-NegativePatterns'` can be also
written as `'-NegativePatterns'`.
For example:
* `./foo_test` Has no flag, and thus runs all its tests.
* `./foo_test --gtest_filter=*` Also runs everything, due to the single match-everything `*` value.
* `./foo_test --gtest_filter=FooTest.*` Runs everything in test case `FooTest`.
* `./foo_test --gtest_filter=*Null*:*Constructor*` Runs any test whose full name contains either `"Null"` or `"Constructor"`.
* `./foo_test --gtest_filter=-*DeathTest.*` Runs all non-death tests.
* `./foo_test --gtest_filter=FooTest.*-FooTest.Bar` Runs everything in test case `FooTest` except `FooTest.Bar`.
_Availability:_ Linux, Windows, Mac.
### Temporarily Disabling Tests ###
If you have a broken test that you cannot fix right away, you can add the
`DISABLED_` prefix to its name. This will exclude it from execution. This is
better than commenting out the code or using `#if 0`, as disabled tests are
still compiled (and thus won't rot).
If you need to disable all tests in a test case, you can either add `DISABLED_`
to the front of the name of each test, or alternatively add it to the front of
the test case name.
For example, the following tests won't be run by Google Test, even though they
will still be compiled:
```
// Tests that Foo does Abc.
TEST(FooTest, DISABLED_DoesAbc) { ... }
class DISABLED_BarTest : public ::testing::Test { ... };
// Tests that Bar does Xyz.
TEST_F(DISABLED_BarTest, DoesXyz) { ... }
```
_Note:_ This feature should only be used for temporary pain-relief. You still
have to fix the disabled tests at a later date. As a reminder, Google Test will
print a banner warning you if a test program contains any disabled tests.
_Tip:_ You can easily count the number of disabled tests you have
using `grep`. This number can be used as a metric for improving your
test quality.
_Availability:_ Linux, Windows, Mac.
### Temporarily Enabling Disabled Tests ###
To include [disabled tests](#temporarily-disabling-tests) in test
execution, just invoke the test program with the
`--gtest_also_run_disabled_tests` flag or set the
`GTEST_ALSO_RUN_DISABLED_TESTS` environment variable to a value other
than `0`. You can combine this with the
[--gtest\_filter](#running-a-subset-of-the-tests) flag to further select
which disabled tests to run.
_Availability:_ Linux, Windows, Mac; since version 1.3.0.
## Repeating the Tests ##
Once in a while you'll run into a test whose result is hit-or-miss. Perhaps it
will fail only 1% of the time, making it rather hard to reproduce the bug under
a debugger. This can be a major source of frustration.
The `--gtest_repeat` flag allows you to repeat all (or selected) test methods
in a program many times. Hopefully, a flaky test will eventually fail and give
you a chance to debug. Here's how to use it:
| `$ foo_test --gtest_repeat=1000` | Repeat foo\_test 1000 times and don't stop at failures. |
|:---------------------------------|:--------------------------------------------------------|
| `$ foo_test --gtest_repeat=-1` | A negative count means repeating forever. |
| `$ foo_test --gtest_repeat=1000 --gtest_break_on_failure` | Repeat foo\_test 1000 times, stopping at the first failure. This is especially useful when running under a debugger: when the testfails, it will drop into the debugger and you can then inspect variables and stacks. |
| `$ foo_test --gtest_repeat=1000 --gtest_filter=FooBar` | Repeat the tests whose name matches the filter 1000 times. |
If your test program contains global set-up/tear-down code registered
using `AddGlobalTestEnvironment()`, it will be repeated in each
iteration as well, as the flakiness may be in it. You can also specify
the repeat count by setting the `GTEST_REPEAT` environment variable.
_Availability:_ Linux, Windows, Mac.
## Shuffling the Tests ##
You can specify the `--gtest_shuffle` flag (or set the `GTEST_SHUFFLE`
environment variable to `1`) to run the tests in a program in a random
order. This helps to reveal bad dependencies between tests.
By default, Google Test uses a random seed calculated from the current
time. Therefore you'll get a different order every time. The console
output includes the random seed value, such that you can reproduce an
order-related test failure later. To specify the random seed
explicitly, use the `--gtest_random_seed=SEED` flag (or set the
`GTEST_RANDOM_SEED` environment variable), where `SEED` is an integer
between 0 and 99999. The seed value 0 is special: it tells Google Test
to do the default behavior of calculating the seed from the current
time.
If you combine this with `--gtest_repeat=N`, Google Test will pick a
different random seed and re-shuffle the tests in each iteration.
_Availability:_ Linux, Windows, Mac; since v1.4.0.
## Controlling Test Output ##
This section teaches how to tweak the way test results are reported.
### Colored Terminal Output ###
Google Test can use colors in its terminal output to make it easier to spot
the separation between tests, and whether tests passed.
You can set the GTEST\_COLOR environment variable or set the `--gtest_color`
command line flag to `yes`, `no`, or `auto` (the default) to enable colors,
disable colors, or let Google Test decide. When the value is `auto`, Google
Test will use colors if and only if the output goes to a terminal and (on
non-Windows platforms) the `TERM` environment variable is set to `xterm` or
`xterm-color`.
_Availability:_ Linux, Windows, Mac.
### Suppressing the Elapsed Time ###
By default, Google Test prints the time it takes to run each test. To
suppress that, run the test program with the `--gtest_print_time=0`
command line flag. Setting the `GTEST_PRINT_TIME` environment
variable to `0` has the same effect.
_Availability:_ Linux, Windows, Mac. (In Google Test 1.3.0 and lower,
the default behavior is that the elapsed time is **not** printed.)
### Generating an XML Report ###
Google Test can emit a detailed XML report to a file in addition to its normal
textual output. The report contains the duration of each test, and thus can
help you identify slow tests.
To generate the XML report, set the `GTEST_OUTPUT` environment variable or the
`--gtest_output` flag to the string `"xml:_path_to_output_file_"`, which will
create the file at the given location. You can also just use the string
`"xml"`, in which case the output can be found in the `test_detail.xml` file in
the current directory.
If you specify a directory (for example, `"xml:output/directory/"` on Linux or
`"xml:output\directory\"` on Windows), Google Test will create the XML file in
that directory, named after the test executable (e.g. `foo_test.xml` for test
program `foo_test` or `foo_test.exe`). If the file already exists (perhaps left
over from a previous run), Google Test will pick a different name (e.g.
`foo_test_1.xml`) to avoid overwriting it.
The report uses the format described here. It is based on the
`junitreport` Ant task and can be parsed by popular continuous build
systems like [Hudson](https://hudson.dev.java.net/). Since that format
was originally intended for Java, a little interpretation is required
to make it apply to Google Test tests, as shown here:
```
<testsuites name="AllTests" ...>
<testsuite name="test_case_name" ...>
<testcase name="test_name" ...>
<failure message="..."/>
<failure message="..."/>
<failure message="..."/>
</testcase>
</testsuite>
</testsuites>
```
* The root `<testsuites>` element corresponds to the entire test program.
* `<testsuite>` elements correspond to Google Test test cases.
* `<testcase>` elements correspond to Google Test test functions.
For instance, the following program
```
TEST(MathTest, Addition) { ... }
TEST(MathTest, Subtraction) { ... }
TEST(LogicTest, NonContradiction) { ... }
```
could generate this report:
```
<?xml version="1.0" encoding="UTF-8"?>
<testsuites tests="3" failures="1" errors="0" time="35" name="AllTests">
<testsuite name="MathTest" tests="2" failures="1" errors="0" time="15">
<testcase name="Addition" status="run" time="7" classname="">
<failure message="Value of: add(1, 1)&#x0A; Actual: 3&#x0A;Expected: 2" type=""/>
<failure message="Value of: add(1, -1)&#x0A; Actual: 1&#x0A;Expected: 0" type=""/>
</testcase>
<testcase name="Subtraction" status="run" time="5" classname="">
</testcase>
</testsuite>
<testsuite name="LogicTest" tests="1" failures="0" errors="0" time="5">
<testcase name="NonContradiction" status="run" time="5" classname="">
</testcase>
</testsuite>
</testsuites>
```
Things to note:
* The `tests` attribute of a `<testsuites>` or `<testsuite>` element tells how many test functions the Google Test program or test case contains, while the `failures` attribute tells how many of them failed.
* The `time` attribute expresses the duration of the test, test case, or entire test program in milliseconds.
* Each `<failure>` element corresponds to a single failed Google Test assertion.
* Some JUnit concepts don't apply to Google Test, yet we have to conform to the DTD. Therefore you'll see some dummy elements and attributes in the report. You can safely ignore these parts.
_Availability:_ Linux, Windows, Mac.
## Controlling How Failures Are Reported ##
### Turning Assertion Failures into Break-Points ###
When running test programs under a debugger, it's very convenient if the
debugger can catch an assertion failure and automatically drop into interactive
mode. Google Test's _break-on-failure_ mode supports this behavior.
To enable it, set the `GTEST_BREAK_ON_FAILURE` environment variable to a value
other than `0` . Alternatively, you can use the `--gtest_break_on_failure`
command line flag.
_Availability:_ Linux, Windows, Mac.
### Disabling Catching Test-Thrown Exceptions ###
Google Test can be used either with or without exceptions enabled. If
a test throws a C++ exception or (on Windows) a structured exception
(SEH), by default Google Test catches it, reports it as a test
failure, and continues with the next test method. This maximizes the
coverage of a test run. Also, on Windows an uncaught exception will
cause a pop-up window, so catching the exceptions allows you to run
the tests automatically.
When debugging the test failures, however, you may instead want the
exceptions to be handled by the debugger, such that you can examine
the call stack when an exception is thrown. To achieve that, set the
`GTEST_CATCH_EXCEPTIONS` environment variable to `0`, or use the
`--gtest_catch_exceptions=0` flag when running the tests.
**Availability**: Linux, Windows, Mac.
### Letting Another Testing Framework Drive ###
If you work on a project that has already been using another testing
framework and is not ready to completely switch to Google Test yet,
you can get much of Google Test's benefit by using its assertions in
your existing tests. Just change your `main()` function to look
like:
```
#include "gtest/gtest.h"
int main(int argc, char** argv) {
::testing::GTEST_FLAG(throw_on_failure) = true;
// Important: Google Test must be initialized.
::testing::InitGoogleTest(&argc, argv);
... whatever your existing testing framework requires ...
}
```
With that, you can use Google Test assertions in addition to the
native assertions your testing framework provides, for example:
```
void TestFooDoesBar() {
Foo foo;
EXPECT_LE(foo.Bar(1), 100); // A Google Test assertion.
CPPUNIT_ASSERT(foo.IsEmpty()); // A native assertion.
}
```
If a Google Test assertion fails, it will print an error message and
throw an exception, which will be treated as a failure by your host
testing framework. If you compile your code with exceptions disabled,
a failed Google Test assertion will instead exit your program with a
non-zero code, which will also signal a test failure to your test
runner.
If you don't write `::testing::GTEST_FLAG(throw_on_failure) = true;` in
your `main()`, you can alternatively enable this feature by specifying
the `--gtest_throw_on_failure` flag on the command-line or setting the
`GTEST_THROW_ON_FAILURE` environment variable to a non-zero value.
Death tests are _not_ supported when other test framework is used to organize tests.
_Availability:_ Linux, Windows, Mac; since v1.3.0.
## Distributing Test Functions to Multiple Machines ##
If you have more than one machine you can use to run a test program,
you might want to run the test functions in parallel and get the
result faster. We call this technique _sharding_, where each machine
is called a _shard_.
Google Test is compatible with test sharding. To take advantage of
this feature, your test runner (not part of Google Test) needs to do
the following:
1. Allocate a number of machines (shards) to run the tests.
1. On each shard, set the `GTEST_TOTAL_SHARDS` environment variable to the total number of shards. It must be the same for all shards.
1. On each shard, set the `GTEST_SHARD_INDEX` environment variable to the index of the shard. Different shards must be assigned different indices, which must be in the range `[0, GTEST_TOTAL_SHARDS - 1]`.
1. Run the same test program on all shards. When Google Test sees the above two environment variables, it will select a subset of the test functions to run. Across all shards, each test function in the program will be run exactly once.
1. Wait for all shards to finish, then collect and report the results.
Your project may have tests that were written without Google Test and
thus don't understand this protocol. In order for your test runner to
figure out which test supports sharding, it can set the environment
variable `GTEST_SHARD_STATUS_FILE` to a non-existent file path. If a
test program supports sharding, it will create this file to
acknowledge the fact (the actual contents of the file are not
important at this time; although we may stick some useful information
in it in the future.); otherwise it will not create it.
Here's an example to make it clear. Suppose you have a test program
`foo_test` that contains the following 5 test functions:
```
TEST(A, V)
TEST(A, W)
TEST(B, X)
TEST(B, Y)
TEST(B, Z)
```
and you have 3 machines at your disposal. To run the test functions in
parallel, you would set `GTEST_TOTAL_SHARDS` to 3 on all machines, and
set `GTEST_SHARD_INDEX` to 0, 1, and 2 on the machines respectively.
Then you would run the same `foo_test` on each machine.
Google Test reserves the right to change how the work is distributed
across the shards, but here's one possible scenario:
* Machine #0 runs `A.V` and `B.X`.
* Machine #1 runs `A.W` and `B.Y`.
* Machine #2 runs `B.Z`.
_Availability:_ Linux, Windows, Mac; since version 1.3.0.
# Fusing Google Test Source Files #
Google Test's implementation consists of ~30 files (excluding its own
tests). Sometimes you may want them to be packaged up in two files (a
`.h` and a `.cc`) instead, such that you can easily copy them to a new
machine and start hacking there. For this we provide an experimental
Python script `fuse_gtest_files.py` in the `scripts/` directory (since release 1.3.0).
Assuming you have Python 2.4 or above installed on your machine, just
go to that directory and run
```
python fuse_gtest_files.py OUTPUT_DIR
```
and you should see an `OUTPUT_DIR` directory being created with files
`gtest/gtest.h` and `gtest/gtest-all.cc` in it. These files contain
everything you need to use Google Test. Just copy them to anywhere
you want and you are ready to write tests. You can use the
[scripts/test/Makefile](../scripts/test/Makefile)
file as an example on how to compile your tests against them.
# Where to Go from Here #
Congratulations! You've now learned more advanced Google Test tools and are
ready to tackle more complex testing tasks. If you want to dive even deeper, you
can read the [Frequently-Asked Questions](FAQ.md).
test/gtest-1.8.0/googletest/docs/DevGuide.md 0 → 100644
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If you are interested in understanding the internals of Google Test,
building from source, or contributing ideas or modifications to the
project, then this document is for you.
# Introduction #
First, let's give you some background of the project.
## Licensing ##
All Google Test source and pre-built packages are provided under the [New BSD License](http://www.opensource.org/licenses/bsd-license.php).
## The Google Test Community ##
The Google Test community exists primarily through the [discussion group](http://groups.google.com/group/googletestframework) and the GitHub repository.
You are definitely encouraged to contribute to the
discussion and you can also help us to keep the effectiveness of the
group high by following and promoting the guidelines listed here.
### Please Be Friendly ###
Showing courtesy and respect to others is a vital part of the Google
culture, and we strongly encourage everyone participating in Google
Test development to join us in accepting nothing less. Of course,
being courteous is not the same as failing to constructively disagree
with each other, but it does mean that we should be respectful of each
other when enumerating the 42 technical reasons that a particular
proposal may not be the best choice. There's never a reason to be
antagonistic or dismissive toward anyone who is sincerely trying to
contribute to a discussion.
Sure, C++ testing is serious business and all that, but it's also
a lot of fun. Let's keep it that way. Let's strive to be one of the
friendliest communities in all of open source.
As always, discuss Google Test in the official GoogleTest discussion group.
You don't have to actually submit code in order to sign up. Your participation
itself is a valuable contribution.
# Working with the Code #
If you want to get your hands dirty with the code inside Google Test,
this is the section for you.
## Compiling from Source ##
Once you check out the code, you can find instructions on how to
compile it in the [README](../README.md) file.
## Testing ##
A testing framework is of no good if itself is not thoroughly tested.
Tests should be written for any new code, and changes should be
verified to not break existing tests before they are submitted for
review. To perform the tests, follow the instructions in
[README](../README.md) and verify that there are no failures.
# Contributing Code #
We are excited that Google Test is now open source, and hope to get
great patches from the community. Before you fire up your favorite IDE
and begin hammering away at that new feature, though, please take the
time to read this section and understand the process. While it seems
rigorous, we want to keep a high standard of quality in the code
base.
## Contributor License Agreements ##
You must sign a Contributor License Agreement (CLA) before we can
accept any code. The CLA protects you and us.
* If you are an individual writing original source code and you're sure you own the intellectual property, then you'll need to sign an [individual CLA](http://code.google.com/legal/individual-cla-v1.0.html).
* If you work for a company that wants to allow you to contribute your work to Google Test, then you'll need to sign a [corporate CLA](http://code.google.com/legal/corporate-cla-v1.0.html).
Follow either of the two links above to access the appropriate CLA and
instructions for how to sign and return it.
## Coding Style ##
To keep the source consistent, readable, diffable and easy to merge,
we use a fairly rigid coding style, as defined by the [google-styleguide](http://code.google.com/p/google-styleguide/) project. All patches will be expected
to conform to the style outlined [here](http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml).
## Updating Generated Code ##
Some of Google Test's source files are generated by the Pump tool (a
Python script). If you need to update such files, please modify the
source (`foo.h.pump`) and re-generate the C++ file using Pump. You
can read the PumpManual for details.
## Submitting Patches ##
Please do submit code. Here's what you need to do:
1. A submission should be a set of changes that addresses one issue in the [issue tracker](https://github.com/google/googletest/issues). Please don't mix more than one logical change per submittal, because it makes the history hard to follow. If you want to make a change that doesn't have a corresponding issue in the issue tracker, please create one.
1. Also, coordinate with team members that are listed on the issue in question. This ensures that work isn't being duplicated and communicating your plan early also generally leads to better patches.
1. Ensure that your code adheres to the [Google Test source code style](#Coding_Style.md).
1. Ensure that there are unit tests for your code.
1. Sign a Contributor License Agreement.
1. Create a Pull Request in the usual way.
## Google Test Committers ##
The current members of the Google Test engineering team are the only
committers at present. In the great tradition of eating one's own
dogfood, we will be requiring each new Google Test engineering team
member to earn the right to become a committer by following the
procedures in this document, writing consistently great code, and
demonstrating repeatedly that he or she truly gets the zen of Google
Test.
# Release Process #
We follow a typical release process:
1. A release branch named `release-X.Y` is created.
1. Bugs are fixed and features are added in trunk; those individual patches are merged into the release branch until it's stable.
1. An individual point release (the `Z` in `X.Y.Z`) is made by creating a tag from the branch.
1. Repeat steps 2 and 3 throughout one release cycle (as determined by features or time).
1. Go back to step 1 to create another release branch and so on.
---
This page is based on the [Making GWT Better](http://code.google.com/webtoolkit/makinggwtbetter.html) guide from the [Google Web Toolkit](http://code.google.com/webtoolkit/) project. Except as otherwise [noted](http://code.google.com/policies.html#restrictions), the content of this page is licensed under the [Creative Commons Attribution 2.5 License](http://creativecommons.org/licenses/by/2.5/).
test/gtest-1.8.0/googletest/docs/Documentation.md 0 → 100644
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This page lists all documentation wiki pages for Google Test **(the SVN trunk version)**
-- **if you use a released version of Google Test, please read the
documentation for that specific version instead.**
* [Primer](Primer.md) -- start here if you are new to Google Test.
* [Samples](Samples.md) -- learn from examples.
* [AdvancedGuide](AdvancedGuide.md) -- learn more about Google Test.
* [XcodeGuide](XcodeGuide.md) -- how to use Google Test in Xcode on Mac.
* [Frequently-Asked Questions](FAQ.md) -- check here before asking a question on the mailing list.
To contribute code to Google Test, read:
* [DevGuide](DevGuide.md) -- read this _before_ writing your first patch.
* [PumpManual](PumpManual.md) -- how we generate some of Google Test's source files.
\ No newline at end of file
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If you cannot find the answer to your question here, and you have read
[Primer](Primer.md) and [AdvancedGuide](AdvancedGuide.md), send it to
googletestframework@googlegroups.com.
## Why should I use Google Test instead of my favorite C++ testing framework? ##
First, let us say clearly that we don't want to get into the debate of
which C++ testing framework is **the best**. There exist many fine
frameworks for writing C++ tests, and we have tremendous respect for
the developers and users of them. We don't think there is (or will
be) a single best framework - you have to pick the right tool for the
particular task you are tackling.
We created Google Test because we couldn't find the right combination
of features and conveniences in an existing framework to satisfy _our_
needs. The following is a list of things that _we_ like about Google
Test. We don't claim them to be unique to Google Test - rather, the
combination of them makes Google Test the choice for us. We hope this
list can help you decide whether it is for you too.
* Google Test is designed to be portable: it doesn't require exceptions or RTTI; it works around various bugs in various compilers and environments; etc. As a result, it works on Linux, Mac OS X, Windows and several embedded operating systems.
* Nonfatal assertions (`EXPECT_*`) have proven to be great time savers, as they allow a test to report multiple failures in a single edit-compile-test cycle.
* It's easy to write assertions that generate informative messages: you just use the stream syntax to append any additional information, e.g. `ASSERT_EQ(5, Foo(i)) << " where i = " << i;`. It doesn't require a new set of macros or special functions.
* Google Test automatically detects your tests and doesn't require you to enumerate them in order to run them.
* Death tests are pretty handy for ensuring that your asserts in production code are triggered by the right conditions.
* `SCOPED_TRACE` helps you understand the context of an assertion failure when it comes from inside a sub-routine or loop.
* You can decide which tests to run using name patterns. This saves time when you want to quickly reproduce a test failure.
* Google Test can generate XML test result reports that can be parsed by popular continuous build system like Hudson.
* Simple things are easy in Google Test, while hard things are possible: in addition to advanced features like [global test environments](AdvancedGuide.md#global-set-up-and-tear-down) and tests parameterized by [values](AdvancedGuide.md#value-parameterized-tests) or [types](docs/AdvancedGuide.md#typed-tests), Google Test supports various ways for the user to extend the framework -- if Google Test doesn't do something out of the box, chances are that a user can implement the feature using Google Test's public API, without changing Google Test itself. In particular, you can:
* expand your testing vocabulary by defining [custom predicates](AdvancedGuide.md#predicate-assertions-for-better-error-messages),
* teach Google Test how to [print your types](AdvancedGuide.md#teaching-google-test-how-to-print-your-values),
* define your own testing macros or utilities and verify them using Google Test's [Service Provider Interface](AdvancedGuide.md#catching-failures), and
* reflect on the test cases or change the test output format by intercepting the [test events](AdvancedGuide.md#extending-google-test-by-handling-test-events).
## I'm getting warnings when compiling Google Test. Would you fix them? ##
We strive to minimize compiler warnings Google Test generates. Before releasing a new version, we test to make sure that it doesn't generate warnings when compiled using its CMake script on Windows, Linux, and Mac OS.
Unfortunately, this doesn't mean you are guaranteed to see no warnings when compiling Google Test in your environment:
* You may be using a different compiler as we use, or a different version of the same compiler. We cannot possibly test for all compilers.
* You may be compiling on a different platform as we do.
* Your project may be using different compiler flags as we do.
It is not always possible to make Google Test warning-free for everyone. Or, it may not be desirable if the warning is rarely enabled and fixing the violations makes the code more complex.
If you see warnings when compiling Google Test, we suggest that you use the `-isystem` flag (assuming your are using GCC) to mark Google Test headers as system headers. That'll suppress warnings from Google Test headers.
## Why should not test case names and test names contain underscore? ##
Underscore (`_`) is special, as C++ reserves the following to be used by
the compiler and the standard library:
1. any identifier that starts with an `_` followed by an upper-case letter, and
1. any identifier that containers two consecutive underscores (i.e. `__`) _anywhere_ in its name.
User code is _prohibited_ from using such identifiers.
Now let's look at what this means for `TEST` and `TEST_F`.
Currently `TEST(TestCaseName, TestName)` generates a class named
`TestCaseName_TestName_Test`. What happens if `TestCaseName` or `TestName`
contains `_`?
1. If `TestCaseName` starts with an `_` followed by an upper-case letter (say, `_Foo`), we end up with `_Foo_TestName_Test`, which is reserved and thus invalid.
1. If `TestCaseName` ends with an `_` (say, `Foo_`), we get `Foo__TestName_Test`, which is invalid.
1. If `TestName` starts with an `_` (say, `_Bar`), we get `TestCaseName__Bar_Test`, which is invalid.
1. If `TestName` ends with an `_` (say, `Bar_`), we get `TestCaseName_Bar__Test`, which is invalid.
So clearly `TestCaseName` and `TestName` cannot start or end with `_`
(Actually, `TestCaseName` can start with `_` -- as long as the `_` isn't
followed by an upper-case letter. But that's getting complicated. So
for simplicity we just say that it cannot start with `_`.).
It may seem fine for `TestCaseName` and `TestName` to contain `_` in the
middle. However, consider this:
``` cpp
TEST(Time, Flies_Like_An_Arrow) { ... }
TEST(Time_Flies, Like_An_Arrow) { ... }
```
Now, the two `TEST`s will both generate the same class
(`Time_Files_Like_An_Arrow_Test`). That's not good.
So for simplicity, we just ask the users to avoid `_` in `TestCaseName`
and `TestName`. The rule is more constraining than necessary, but it's
simple and easy to remember. It also gives Google Test some wiggle
room in case its implementation needs to change in the future.
If you violate the rule, there may not be immediately consequences,
but your test may (just may) break with a new compiler (or a new
version of the compiler you are using) or with a new version of Google
Test. Therefore it's best to follow the rule.
## Why is it not recommended to install a pre-compiled copy of Google Test (for example, into /usr/local)? ##
In the early days, we said that you could install
compiled Google Test libraries on `*`nix systems using `make install`.
Then every user of your machine can write tests without
recompiling Google Test.
This seemed like a good idea, but it has a
got-cha: every user needs to compile his tests using the _same_ compiler
flags used to compile the installed Google Test libraries; otherwise
he may run into undefined behaviors (i.e. the tests can behave
strangely and may even crash for no obvious reasons).
Why? Because C++ has this thing called the One-Definition Rule: if
two C++ source files contain different definitions of the same
class/function/variable, and you link them together, you violate the
rule. The linker may or may not catch the error (in many cases it's
not required by the C++ standard to catch the violation). If it
doesn't, you get strange run-time behaviors that are unexpected and
hard to debug.
If you compile Google Test and your test code using different compiler
flags, they may see different definitions of the same
class/function/variable (e.g. due to the use of `#if` in Google Test).
Therefore, for your sanity, we recommend to avoid installing pre-compiled
Google Test libraries. Instead, each project should compile
Google Test itself such that it can be sure that the same flags are
used for both Google Test and the tests.
## How do I generate 64-bit binaries on Windows (using Visual Studio 2008)? ##
(Answered by Trevor Robinson)
Load the supplied Visual Studio solution file, either `msvc\gtest-md.sln` or
`msvc\gtest.sln`. Go through the migration wizard to migrate the
solution and project files to Visual Studio 2008. Select
`Configuration Manager...` from the `Build` menu. Select `<New...>` from
the `Active solution platform` dropdown. Select `x64` from the new
platform dropdown, leave `Copy settings from` set to `Win32` and
`Create new project platforms` checked, then click `OK`. You now have
`Win32` and `x64` platform configurations, selectable from the
`Standard` toolbar, which allow you to toggle between building 32-bit or
64-bit binaries (or both at once using Batch Build).
In order to prevent build output files from overwriting one another,
you'll need to change the `Intermediate Directory` settings for the
newly created platform configuration across all the projects. To do
this, multi-select (e.g. using shift-click) all projects (but not the
solution) in the `Solution Explorer`. Right-click one of them and
select `Properties`. In the left pane, select `Configuration Properties`,
and from the `Configuration` dropdown, select `All Configurations`.
Make sure the selected platform is `x64`. For the
`Intermediate Directory` setting, change the value from
`$(PlatformName)\$(ConfigurationName)` to
`$(OutDir)\$(ProjectName)`. Click `OK` and then build the
solution. When the build is complete, the 64-bit binaries will be in
the `msvc\x64\Debug` directory.
## Can I use Google Test on MinGW? ##
We haven't tested this ourselves, but Per Abrahamsen reported that he
was able to compile and install Google Test successfully when using
MinGW from Cygwin. You'll need to configure it with:
`PATH/TO/configure CC="gcc -mno-cygwin" CXX="g++ -mno-cygwin"`
You should be able to replace the `-mno-cygwin` option with direct links
to the real MinGW binaries, but we haven't tried that.
Caveats:
* There are many warnings when compiling.
* `make check` will produce some errors as not all tests for Google Test itself are compatible with MinGW.
We also have reports on successful cross compilation of Google Test
MinGW binaries on Linux using
[these instructions](http://wiki.wxwidgets.org/Cross-Compiling_Under_Linux#Cross-compiling_under_Linux_for_MS_Windows)
on the WxWidgets site.
Please contact `googletestframework@googlegroups.com` if you are
interested in improving the support for MinGW.
## Why does Google Test support EXPECT\_EQ(NULL, ptr) and ASSERT\_EQ(NULL, ptr) but not EXPECT\_NE(NULL, ptr) and ASSERT\_NE(NULL, ptr)? ##
Due to some peculiarity of C++, it requires some non-trivial template
meta programming tricks to support using `NULL` as an argument of the
`EXPECT_XX()` and `ASSERT_XX()` macros. Therefore we only do it where
it's most needed (otherwise we make the implementation of Google Test
harder to maintain and more error-prone than necessary).
The `EXPECT_EQ()` macro takes the _expected_ value as its first
argument and the _actual_ value as the second. It's reasonable that
someone wants to write `EXPECT_EQ(NULL, some_expression)`, and this
indeed was requested several times. Therefore we implemented it.
The need for `EXPECT_NE(NULL, ptr)` isn't nearly as strong. When the
assertion fails, you already know that `ptr` must be `NULL`, so it
doesn't add any information to print ptr in this case. That means
`EXPECT_TRUE(ptr != NULL)` works just as well.
If we were to support `EXPECT_NE(NULL, ptr)`, for consistency we'll
have to support `EXPECT_NE(ptr, NULL)` as well, as unlike `EXPECT_EQ`,
we don't have a convention on the order of the two arguments for
`EXPECT_NE`. This means using the template meta programming tricks
twice in the implementation, making it even harder to understand and
maintain. We believe the benefit doesn't justify the cost.
Finally, with the growth of Google Mock's [matcher](../../googlemock/docs/CookBook.md#using-matchers-in-google-test-assertions) library, we are
encouraging people to use the unified `EXPECT_THAT(value, matcher)`
syntax more often in tests. One significant advantage of the matcher
approach is that matchers can be easily combined to form new matchers,
while the `EXPECT_NE`, etc, macros cannot be easily
combined. Therefore we want to invest more in the matchers than in the
`EXPECT_XX()` macros.
## Does Google Test support running tests in parallel? ##
Test runners tend to be tightly coupled with the build/test
environment, and Google Test doesn't try to solve the problem of
running tests in parallel. Instead, we tried to make Google Test work
nicely with test runners. For example, Google Test's XML report
contains the time spent on each test, and its `gtest_list_tests` and
`gtest_filter` flags can be used for splitting the execution of test
methods into multiple processes. These functionalities can help the
test runner run the tests in parallel.
## Why don't Google Test run the tests in different threads to speed things up? ##
It's difficult to write thread-safe code. Most tests are not written
with thread-safety in mind, and thus may not work correctly in a
multi-threaded setting.
If you think about it, it's already hard to make your code work when
you know what other threads are doing. It's much harder, and
sometimes even impossible, to make your code work when you don't know
what other threads are doing (remember that test methods can be added,
deleted, or modified after your test was written). If you want to run
the tests in parallel, you'd better run them in different processes.
## Why aren't Google Test assertions implemented using exceptions? ##
Our original motivation was to be able to use Google Test in projects
that disable exceptions. Later we realized some additional benefits
of this approach:
1. Throwing in a destructor is undefined behavior in C++. Not using exceptions means Google Test's assertions are safe to use in destructors.
1. The `EXPECT_*` family of macros will continue even after a failure, allowing multiple failures in a `TEST` to be reported in a single run. This is a popular feature, as in C++ the edit-compile-test cycle is usually quite long and being able to fixing more than one thing at a time is a blessing.
1. If assertions are implemented using exceptions, a test may falsely ignore a failure if it's caught by user code:
``` cpp
try { ... ASSERT_TRUE(...) ... }
catch (...) { ... }
```
The above code will pass even if the `ASSERT_TRUE` throws. While it's unlikely for someone to write this in a test, it's possible to run into this pattern when you write assertions in callbacks that are called by the code under test.
The downside of not using exceptions is that `ASSERT_*` (implemented
using `return`) will only abort the current function, not the current
`TEST`.
## Why do we use two different macros for tests with and without fixtures? ##
Unfortunately, C++'s macro system doesn't allow us to use the same
macro for both cases. One possibility is to provide only one macro
for tests with fixtures, and require the user to define an empty
fixture sometimes:
``` cpp
class FooTest : public ::testing::Test {};
TEST_F(FooTest, DoesThis) { ... }
```
or
``` cpp
typedef ::testing::Test FooTest;
TEST_F(FooTest, DoesThat) { ... }
```
Yet, many people think this is one line too many. :-) Our goal was to
make it really easy to write tests, so we tried to make simple tests
trivial to create. That means using a separate macro for such tests.
We think neither approach is ideal, yet either of them is reasonable.
In the end, it probably doesn't matter much either way.
## Why don't we use structs as test fixtures? ##
We like to use structs only when representing passive data. This
distinction between structs and classes is good for documenting the
intent of the code's author. Since test fixtures have logic like
`SetUp()` and `TearDown()`, they are better defined as classes.
## Why are death tests implemented as assertions instead of using a test runner? ##
Our goal was to make death tests as convenient for a user as C++
possibly allows. In particular:
* The runner-style requires to split the information into two pieces: the definition of the death test itself, and the specification for the runner on how to run the death test and what to expect. The death test would be written in C++, while the runner spec may or may not be. A user needs to carefully keep the two in sync. `ASSERT_DEATH(statement, expected_message)` specifies all necessary information in one place, in one language, without boilerplate code. It is very declarative.
* `ASSERT_DEATH` has a similar syntax and error-reporting semantics as other Google Test assertions, and thus is easy to learn.
* `ASSERT_DEATH` can be mixed with other assertions and other logic at your will. You are not limited to one death test per test method. For example, you can write something like:
``` cpp
if (FooCondition()) {
ASSERT_DEATH(Bar(), "blah");
} else {
ASSERT_EQ(5, Bar());
}
```
If you prefer one death test per test method, you can write your tests in that style too, but we don't want to impose that on the users. The fewer artificial limitations the better.
* `ASSERT_DEATH` can reference local variables in the current function, and you can decide how many death tests you want based on run-time information. For example,
``` cpp
const int count = GetCount(); // Only known at run time.
for (int i = 1; i <= count; i++) {
ASSERT_DEATH({
double* buffer = new double[i];
... initializes buffer ...
Foo(buffer, i)
}, "blah blah");
}
```
The runner-based approach tends to be more static and less flexible, or requires more user effort to get this kind of flexibility.
Another interesting thing about `ASSERT_DEATH` is that it calls `fork()`
to create a child process to run the death test. This is lightening
fast, as `fork()` uses copy-on-write pages and incurs almost zero
overhead, and the child process starts from the user-supplied
statement directly, skipping all global and local initialization and
any code leading to the given statement. If you launch the child
process from scratch, it can take seconds just to load everything and
start running if the test links to many libraries dynamically.
## My death test modifies some state, but the change seems lost after the death test finishes. Why? ##
Death tests (`EXPECT_DEATH`, etc) are executed in a sub-process s.t. the
expected crash won't kill the test program (i.e. the parent process). As a
result, any in-memory side effects they incur are observable in their
respective sub-processes, but not in the parent process. You can think of them
as running in a parallel universe, more or less.
## The compiler complains about "undefined references" to some static const member variables, but I did define them in the class body. What's wrong? ##
If your class has a static data member:
``` cpp
// foo.h
class Foo {
...
static const int kBar = 100;
};
```
You also need to define it _outside_ of the class body in `foo.cc`:
``` cpp
const int Foo::kBar; // No initializer here.
```
Otherwise your code is **invalid C++**, and may break in unexpected ways. In
particular, using it in Google Test comparison assertions (`EXPECT_EQ`, etc)
will generate an "undefined reference" linker error.
## I have an interface that has several implementations. Can I write a set of tests once and repeat them over all the implementations? ##
Google Test doesn't yet have good support for this kind of tests, or
data-driven tests in general. We hope to be able to make improvements in this
area soon.
## Can I derive a test fixture from another? ##
Yes.
Each test fixture has a corresponding and same named test case. This means only
one test case can use a particular fixture. Sometimes, however, multiple test
cases may want to use the same or slightly different fixtures. For example, you
may want to make sure that all of a GUI library's test cases don't leak
important system resources like fonts and brushes.
In Google Test, you share a fixture among test cases by putting the shared
logic in a base test fixture, then deriving from that base a separate fixture
for each test case that wants to use this common logic. You then use `TEST_F()`
to write tests using each derived fixture.
Typically, your code looks like this:
``` cpp
// Defines a base test fixture.
class BaseTest : public ::testing::Test {
protected:
...
};
// Derives a fixture FooTest from BaseTest.
class FooTest : public BaseTest {
protected:
virtual void SetUp() {
BaseTest::SetUp(); // Sets up the base fixture first.
... additional set-up work ...
}
virtual void TearDown() {
... clean-up work for FooTest ...
BaseTest::TearDown(); // Remember to tear down the base fixture
// after cleaning up FooTest!
}
... functions and variables for FooTest ...
};
// Tests that use the fixture FooTest.
TEST_F(FooTest, Bar) { ... }
TEST_F(FooTest, Baz) { ... }
... additional fixtures derived from BaseTest ...
```
If necessary, you can continue to derive test fixtures from a derived fixture.
Google Test has no limit on how deep the hierarchy can be.
For a complete example using derived test fixtures, see
[sample5](../samples/sample5_unittest.cc).
## My compiler complains "void value not ignored as it ought to be." What does this mean? ##
You're probably using an `ASSERT_*()` in a function that doesn't return `void`.
`ASSERT_*()` can only be used in `void` functions.
## My death test hangs (or seg-faults). How do I fix it? ##
In Google Test, death tests are run in a child process and the way they work is
delicate. To write death tests you really need to understand how they work.
Please make sure you have read this.
In particular, death tests don't like having multiple threads in the parent
process. So the first thing you can try is to eliminate creating threads
outside of `EXPECT_DEATH()`.
Sometimes this is impossible as some library you must use may be creating
threads before `main()` is even reached. In this case, you can try to minimize
the chance of conflicts by either moving as many activities as possible inside
`EXPECT_DEATH()` (in the extreme case, you want to move everything inside), or
leaving as few things as possible in it. Also, you can try to set the death
test style to `"threadsafe"`, which is safer but slower, and see if it helps.
If you go with thread-safe death tests, remember that they rerun the test
program from the beginning in the child process. Therefore make sure your
program can run side-by-side with itself and is deterministic.
In the end, this boils down to good concurrent programming. You have to make
sure that there is no race conditions or dead locks in your program. No silver
bullet - sorry!
## Should I use the constructor/destructor of the test fixture or the set-up/tear-down function? ##
The first thing to remember is that Google Test does not reuse the
same test fixture object across multiple tests. For each `TEST_F`,
Google Test will create a fresh test fixture object, _immediately_
call `SetUp()`, run the test body, call `TearDown()`, and then
_immediately_ delete the test fixture object.
When you need to write per-test set-up and tear-down logic, you have
the choice between using the test fixture constructor/destructor or
`SetUp()/TearDown()`. The former is usually preferred, as it has the
following benefits:
* By initializing a member variable in the constructor, we have the option to make it `const`, which helps prevent accidental changes to its value and makes the tests more obviously correct.
* In case we need to subclass the test fixture class, the subclass' constructor is guaranteed to call the base class' constructor first, and the subclass' destructor is guaranteed to call the base class' destructor afterward. With `SetUp()/TearDown()`, a subclass may make the mistake of forgetting to call the base class' `SetUp()/TearDown()` or call them at the wrong moment.
You may still want to use `SetUp()/TearDown()` in the following rare cases:
* If the tear-down operation could throw an exception, you must use `TearDown()` as opposed to the destructor, as throwing in a destructor leads to undefined behavior and usually will kill your program right away. Note that many standard libraries (like STL) may throw when exceptions are enabled in the compiler. Therefore you should prefer `TearDown()` if you want to write portable tests that work with or without exceptions.
* The assertion macros throw an exception when flag `--gtest_throw_on_failure` is specified. Therefore, you shouldn't use Google Test assertions in a destructor if you plan to run your tests with this flag.
* In a constructor or destructor, you cannot make a virtual function call on this object. (You can call a method declared as virtual, but it will be statically bound.) Therefore, if you need to call a method that will be overriden in a derived class, you have to use `SetUp()/TearDown()`.
## The compiler complains "no matching function to call" when I use ASSERT\_PREDn. How do I fix it? ##
If the predicate function you use in `ASSERT_PRED*` or `EXPECT_PRED*` is
overloaded or a template, the compiler will have trouble figuring out which
overloaded version it should use. `ASSERT_PRED_FORMAT*` and
`EXPECT_PRED_FORMAT*` don't have this problem.
If you see this error, you might want to switch to
`(ASSERT|EXPECT)_PRED_FORMAT*`, which will also give you a better failure
message. If, however, that is not an option, you can resolve the problem by
explicitly telling the compiler which version to pick.
For example, suppose you have
``` cpp
bool IsPositive(int n) {
return n > 0;
}
bool IsPositive(double x) {
return x > 0;
}
```
you will get a compiler error if you write
``` cpp
EXPECT_PRED1(IsPositive, 5);
```
However, this will work:
``` cpp
EXPECT_PRED1(*static_cast<bool (*)(int)>*(IsPositive), 5);
```
(The stuff inside the angled brackets for the `static_cast` operator is the
type of the function pointer for the `int`-version of `IsPositive()`.)
As another example, when you have a template function
``` cpp
template <typename T>
bool IsNegative(T x) {
return x < 0;
}
```
you can use it in a predicate assertion like this:
``` cpp
ASSERT_PRED1(IsNegative*<int>*, -5);
```
Things are more interesting if your template has more than one parameters. The
following won't compile:
``` cpp
ASSERT_PRED2(*GreaterThan<int, int>*, 5, 0);
```
as the C++ pre-processor thinks you are giving `ASSERT_PRED2` 4 arguments,
which is one more than expected. The workaround is to wrap the predicate
function in parentheses:
``` cpp
ASSERT_PRED2(*(GreaterThan<int, int>)*, 5, 0);
```
## My compiler complains about "ignoring return value" when I call RUN\_ALL\_TESTS(). Why? ##
Some people had been ignoring the return value of `RUN_ALL_TESTS()`. That is,
instead of
``` cpp
return RUN_ALL_TESTS();
```
they write
``` cpp
RUN_ALL_TESTS();
```
This is wrong and dangerous. A test runner needs to see the return value of
`RUN_ALL_TESTS()` in order to determine if a test has passed. If your `main()`
function ignores it, your test will be considered successful even if it has a
Google Test assertion failure. Very bad.
To help the users avoid this dangerous bug, the implementation of
`RUN_ALL_TESTS()` causes gcc to raise this warning, when the return value is
ignored. If you see this warning, the fix is simple: just make sure its value
is used as the return value of `main()`.
## My compiler complains that a constructor (or destructor) cannot return a value. What's going on? ##
Due to a peculiarity of C++, in order to support the syntax for streaming
messages to an `ASSERT_*`, e.g.
``` cpp
ASSERT_EQ(1, Foo()) << "blah blah" << foo;
```
we had to give up using `ASSERT*` and `FAIL*` (but not `EXPECT*` and
`ADD_FAILURE*`) in constructors and destructors. The workaround is to move the
content of your constructor/destructor to a private void member function, or
switch to `EXPECT_*()` if that works. This section in the user's guide explains
it.
## My set-up function is not called. Why? ##
C++ is case-sensitive. It should be spelled as `SetUp()`. Did you
spell it as `Setup()`?
Similarly, sometimes people spell `SetUpTestCase()` as `SetupTestCase()` and
wonder why it's never called.
## How do I jump to the line of a failure in Emacs directly? ##
Google Test's failure message format is understood by Emacs and many other
IDEs, like acme and XCode. If a Google Test message is in a compilation buffer
in Emacs, then it's clickable. You can now hit `enter` on a message to jump to
the corresponding source code, or use `C-x `` to jump to the next failure.
## I have several test cases which share the same test fixture logic, do I have to define a new test fixture class for each of them? This seems pretty tedious. ##
You don't have to. Instead of
``` cpp
class FooTest : public BaseTest {};
TEST_F(FooTest, Abc) { ... }
TEST_F(FooTest, Def) { ... }
class BarTest : public BaseTest {};
TEST_F(BarTest, Abc) { ... }
TEST_F(BarTest, Def) { ... }
```
you can simply `typedef` the test fixtures:
``` cpp
typedef BaseTest FooTest;
TEST_F(FooTest, Abc) { ... }
TEST_F(FooTest, Def) { ... }
typedef BaseTest BarTest;
TEST_F(BarTest, Abc) { ... }
TEST_F(BarTest, Def) { ... }
```
## The Google Test output is buried in a whole bunch of log messages. What do I do? ##
The Google Test output is meant to be a concise and human-friendly report. If
your test generates textual output itself, it will mix with the Google Test
output, making it hard to read. However, there is an easy solution to this
problem.
Since most log messages go to stderr, we decided to let Google Test output go
to stdout. This way, you can easily separate the two using redirection. For
example:
```
./my_test > googletest_output.txt
```
## Why should I prefer test fixtures over global variables? ##
There are several good reasons:
1. It's likely your test needs to change the states of its global variables. This makes it difficult to keep side effects from escaping one test and contaminating others, making debugging difficult. By using fixtures, each test has a fresh set of variables that's different (but with the same names). Thus, tests are kept independent of each other.
1. Global variables pollute the global namespace.
1. Test fixtures can be reused via subclassing, which cannot be done easily with global variables. This is useful if many test cases have something in common.
## How do I test private class members without writing FRIEND\_TEST()s? ##
You should try to write testable code, which means classes should be easily
tested from their public interface. One way to achieve this is the Pimpl idiom:
you move all private members of a class into a helper class, and make all
members of the helper class public.
You have several other options that don't require using `FRIEND_TEST`:
* Write the tests as members of the fixture class:
``` cpp
class Foo {
friend class FooTest;
...
};
class FooTest : public ::testing::Test {
protected:
...
void Test1() {...} // This accesses private members of class Foo.
void Test2() {...} // So does this one.
};
TEST_F(FooTest, Test1) {
Test1();
}
TEST_F(FooTest, Test2) {
Test2();
}
```
* In the fixture class, write accessors for the tested class' private members, then use the accessors in your tests:
``` cpp
class Foo {
friend class FooTest;
...
};
class FooTest : public ::testing::Test {
protected:
...
T1 get_private_member1(Foo* obj) {
return obj->private_member1_;
}
};
TEST_F(FooTest, Test1) {
...
get_private_member1(x)
...
}
```
* If the methods are declared **protected**, you can change their access level in a test-only subclass:
``` cpp
class YourClass {
...
protected: // protected access for testability.
int DoSomethingReturningInt();
...
};
// in the your_class_test.cc file:
class TestableYourClass : public YourClass {
...
public: using YourClass::DoSomethingReturningInt; // changes access rights
...
};
TEST_F(YourClassTest, DoSomethingTest) {
TestableYourClass obj;
assertEquals(expected_value, obj.DoSomethingReturningInt());
}
```
## How do I test private class static members without writing FRIEND\_TEST()s? ##
We find private static methods clutter the header file. They are
implementation details and ideally should be kept out of a .h. So often I make
them free functions instead.
Instead of:
``` cpp
// foo.h
class Foo {
...
private:
static bool Func(int n);
};
// foo.cc
bool Foo::Func(int n) { ... }
// foo_test.cc
EXPECT_TRUE(Foo::Func(12345));
```
You probably should better write:
``` cpp
// foo.h
class Foo {
...
};
// foo.cc
namespace internal {
bool Func(int n) { ... }
}
// foo_test.cc
namespace internal {
bool Func(int n);
}
EXPECT_TRUE(internal::Func(12345));
```
## I would like to run a test several times with different parameters. Do I need to write several similar copies of it? ##
No. You can use a feature called [value-parameterized tests](AdvancedGuide.md#Value_Parameterized_Tests) which
lets you repeat your tests with different parameters, without defining it more than once.
## How do I test a file that defines main()? ##
To test a `foo.cc` file, you need to compile and link it into your unit test
program. However, when the file contains a definition for the `main()`
function, it will clash with the `main()` of your unit test, and will result in
a build error.
The right solution is to split it into three files:
1. `foo.h` which contains the declarations,
1. `foo.cc` which contains the definitions except `main()`, and
1. `foo_main.cc` which contains nothing but the definition of `main()`.
Then `foo.cc` can be easily tested.
If you are adding tests to an existing file and don't want an intrusive change
like this, there is a hack: just include the entire `foo.cc` file in your unit
test. For example:
``` cpp
// File foo_unittest.cc
// The headers section
...
// Renames main() in foo.cc to make room for the unit test main()
#define main FooMain
#include "a/b/foo.cc"
// The tests start here.
...
```
However, please remember this is a hack and should only be used as the last
resort.
## What can the statement argument in ASSERT\_DEATH() be? ##
`ASSERT_DEATH(_statement_, _regex_)` (or any death assertion macro) can be used
wherever `_statement_` is valid. So basically `_statement_` can be any C++
statement that makes sense in the current context. In particular, it can
reference global and/or local variables, and can be:
* a simple function call (often the case),
* a complex expression, or
* a compound statement.
Some examples are shown here:
``` cpp
// A death test can be a simple function call.
TEST(MyDeathTest, FunctionCall) {
ASSERT_DEATH(Xyz(5), "Xyz failed");
}
// Or a complex expression that references variables and functions.
TEST(MyDeathTest, ComplexExpression) {
const bool c = Condition();
ASSERT_DEATH((c ? Func1(0) : object2.Method("test")),
"(Func1|Method) failed");
}
// Death assertions can be used any where in a function. In
// particular, they can be inside a loop.
TEST(MyDeathTest, InsideLoop) {
// Verifies that Foo(0), Foo(1), ..., and Foo(4) all die.
for (int i = 0; i < 5; i++) {
EXPECT_DEATH_M(Foo(i), "Foo has \\d+ errors",
::testing::Message() << "where i is " << i);
}
}
// A death assertion can contain a compound statement.
TEST(MyDeathTest, CompoundStatement) {
// Verifies that at lease one of Bar(0), Bar(1), ..., and
// Bar(4) dies.
ASSERT_DEATH({
for (int i = 0; i < 5; i++) {
Bar(i);
}
},
"Bar has \\d+ errors");}
```
`googletest_unittest.cc` contains more examples if you are interested.
## What syntax does the regular expression in ASSERT\_DEATH use? ##
On POSIX systems, Google Test uses the POSIX Extended regular
expression syntax
(http://en.wikipedia.org/wiki/Regular_expression#POSIX_Extended_Regular_Expressions).
On Windows, it uses a limited variant of regular expression
syntax. For more details, see the
[regular expression syntax](AdvancedGuide.md#Regular_Expression_Syntax).
## I have a fixture class Foo, but TEST\_F(Foo, Bar) gives me error "no matching function for call to Foo::Foo()". Why? ##
Google Test needs to be able to create objects of your test fixture class, so
it must have a default constructor. Normally the compiler will define one for
you. However, there are cases where you have to define your own:
* If you explicitly declare a non-default constructor for class `Foo`, then you need to define a default constructor, even if it would be empty.
* If `Foo` has a const non-static data member, then you have to define the default constructor _and_ initialize the const member in the initializer list of the constructor. (Early versions of `gcc` doesn't force you to initialize the const member. It's a bug that has been fixed in `gcc 4`.)
## Why does ASSERT\_DEATH complain about previous threads that were already joined? ##
With the Linux pthread library, there is no turning back once you cross the
line from single thread to multiple threads. The first time you create a
thread, a manager thread is created in addition, so you get 3, not 2, threads.
Later when the thread you create joins the main thread, the thread count
decrements by 1, but the manager thread will never be killed, so you still have
2 threads, which means you cannot safely run a death test.
The new NPTL thread library doesn't suffer from this problem, as it doesn't
create a manager thread. However, if you don't control which machine your test
runs on, you shouldn't depend on this.
## Why does Google Test require the entire test case, instead of individual tests, to be named FOODeathTest when it uses ASSERT\_DEATH? ##
Google Test does not interleave tests from different test cases. That is, it
runs all tests in one test case first, and then runs all tests in the next test
case, and so on. Google Test does this because it needs to set up a test case
before the first test in it is run, and tear it down afterwords. Splitting up
the test case would require multiple set-up and tear-down processes, which is
inefficient and makes the semantics unclean.
If we were to determine the order of tests based on test name instead of test
case name, then we would have a problem with the following situation:
``` cpp
TEST_F(FooTest, AbcDeathTest) { ... }
TEST_F(FooTest, Uvw) { ... }
TEST_F(BarTest, DefDeathTest) { ... }
TEST_F(BarTest, Xyz) { ... }
```
Since `FooTest.AbcDeathTest` needs to run before `BarTest.Xyz`, and we don't
interleave tests from different test cases, we need to run all tests in the
`FooTest` case before running any test in the `BarTest` case. This contradicts
with the requirement to run `BarTest.DefDeathTest` before `FooTest.Uvw`.
## But I don't like calling my entire test case FOODeathTest when it contains both death tests and non-death tests. What do I do? ##
You don't have to, but if you like, you may split up the test case into
`FooTest` and `FooDeathTest`, where the names make it clear that they are
related:
``` cpp
class FooTest : public ::testing::Test { ... };
TEST_F(FooTest, Abc) { ... }
TEST_F(FooTest, Def) { ... }
typedef FooTest FooDeathTest;
TEST_F(FooDeathTest, Uvw) { ... EXPECT_DEATH(...) ... }
TEST_F(FooDeathTest, Xyz) { ... ASSERT_DEATH(...) ... }
```
## The compiler complains about "no match for 'operator<<'" when I use an assertion. What gives? ##
If you use a user-defined type `FooType` in an assertion, you must make sure
there is an `std::ostream& operator<<(std::ostream&, const FooType&)` function
defined such that we can print a value of `FooType`.
In addition, if `FooType` is declared in a name space, the `<<` operator also
needs to be defined in the _same_ name space.
## How do I suppress the memory leak messages on Windows? ##
Since the statically initialized Google Test singleton requires allocations on
the heap, the Visual C++ memory leak detector will report memory leaks at the
end of the program run. The easiest way to avoid this is to use the
`_CrtMemCheckpoint` and `_CrtMemDumpAllObjectsSince` calls to not report any
statically initialized heap objects. See MSDN for more details and additional
heap check/debug routines.
## I am building my project with Google Test in Visual Studio and all I'm getting is a bunch of linker errors (or warnings). Help! ##
You may get a number of the following linker error or warnings if you
attempt to link your test project with the Google Test library when
your project and the are not built using the same compiler settings.
* LNK2005: symbol already defined in object
* LNK4217: locally defined symbol 'symbol' imported in function 'function'
* LNK4049: locally defined symbol 'symbol' imported
The Google Test project (gtest.vcproj) has the Runtime Library option
set to /MT (use multi-threaded static libraries, /MTd for debug). If
your project uses something else, for example /MD (use multi-threaded
DLLs, /MDd for debug), you need to change the setting in the Google
Test project to match your project's.
To update this setting open the project properties in the Visual
Studio IDE then select the branch Configuration Properties | C/C++ |
Code Generation and change the option "Runtime Library". You may also try
using gtest-md.vcproj instead of gtest.vcproj.
## I put my tests in a library and Google Test doesn't run them. What's happening? ##
Have you read a
[warning](Primer.md#important-note-for-visual-c-users) on
the Google Test Primer page?
## I want to use Google Test with Visual Studio but don't know where to start. ##
Many people are in your position and one of the posted his solution to
our mailing list.
## I am seeing compile errors mentioning std::type\_traits when I try to use Google Test on Solaris. ##
Google Test uses parts of the standard C++ library that SunStudio does not support.
Our users reported success using alternative implementations. Try running the build after runing this commad:
`export CC=cc CXX=CC CXXFLAGS='-library=stlport4'`
## How can my code detect if it is running in a test? ##
If you write code that sniffs whether it's running in a test and does
different things accordingly, you are leaking test-only logic into
production code and there is no easy way to ensure that the test-only
code paths aren't run by mistake in production. Such cleverness also
leads to
[Heisenbugs](http://en.wikipedia.org/wiki/Unusual_software_bug#Heisenbug).
Therefore we strongly advise against the practice, and Google Test doesn't
provide a way to do it.
In general, the recommended way to cause the code to behave
differently under test is [dependency injection](http://jamesshore.com/Blog/Dependency-Injection-Demystified.html).
You can inject different functionality from the test and from the
production code. Since your production code doesn't link in the
for-test logic at all, there is no danger in accidentally running it.
However, if you _really_, _really_, _really_ have no choice, and if
you follow the rule of ending your test program names with `_test`,
you can use the _horrible_ hack of sniffing your executable name
(`argv[0]` in `main()`) to know whether the code is under test.
## Google Test defines a macro that clashes with one defined by another library. How do I deal with that? ##
In C++, macros don't obey namespaces. Therefore two libraries that
both define a macro of the same name will clash if you `#include` both
definitions. In case a Google Test macro clashes with another
library, you can force Google Test to rename its macro to avoid the
conflict.
Specifically, if both Google Test and some other code define macro
`FOO`, you can add
```
-DGTEST_DONT_DEFINE_FOO=1
```
to the compiler flags to tell Google Test to change the macro's name
from `FOO` to `GTEST_FOO`. For example, with `-DGTEST_DONT_DEFINE_TEST=1`, you'll need to write
``` cpp
GTEST_TEST(SomeTest, DoesThis) { ... }
```
instead of
``` cpp
TEST(SomeTest, DoesThis) { ... }
```
in order to define a test.
Currently, the following `TEST`, `FAIL`, `SUCCEED`, and the basic comparison assertion macros can have alternative names. You can see the full list of covered macros [here](http://www.google.com/codesearch?q=if+!GTEST_DONT_DEFINE_\w%2B+package:http://googletest\.googlecode\.com+file:/include/gtest/gtest.h). More information can be found in the "Avoiding Macro Name Clashes" section of the README file.
## Is it OK if I have two separate `TEST(Foo, Bar)` test methods defined in different namespaces? ##
Yes.
The rule is **all test methods in the same test case must use the same fixture class**. This means that the following is **allowed** because both tests use the same fixture class (`::testing::Test`).
``` cpp
namespace foo {
TEST(CoolTest, DoSomething) {
SUCCEED();
}
} // namespace foo
namespace bar {
TEST(CoolTest, DoSomething) {
SUCCEED();
}
} // namespace foo
```
However, the following code is **not allowed** and will produce a runtime error from Google Test because the test methods are using different test fixture classes with the same test case name.
``` cpp
namespace foo {
class CoolTest : public ::testing::Test {}; // Fixture foo::CoolTest
TEST_F(CoolTest, DoSomething) {
SUCCEED();
}
} // namespace foo
namespace bar {
class CoolTest : public ::testing::Test {}; // Fixture: bar::CoolTest
TEST_F(CoolTest, DoSomething) {
SUCCEED();
}
} // namespace foo
```
## How do I build Google Testing Framework with Xcode 4? ##
If you try to build Google Test's Xcode project with Xcode 4.0 or later, you may encounter an error message that looks like
"Missing SDK in target gtest\_framework: /Developer/SDKs/MacOSX10.4u.sdk". That means that Xcode does not support the SDK the project is targeting. See the Xcode section in the [README](../README.md) file on how to resolve this.
## My question is not covered in your FAQ! ##
If you cannot find the answer to your question in this FAQ, there are
some other resources you can use:
1. read other [wiki pages](../docs),
1. search the mailing list [archive](https://groups.google.com/forum/#!forum/googletestframework),
1. ask it on [googletestframework@googlegroups.com](mailto:googletestframework@googlegroups.com) and someone will answer it (to prevent spam, we require you to join the [discussion group](http://groups.google.com/group/googletestframework) before you can post.).
Please note that creating an issue in the
[issue tracker](https://github.com/google/googletest/issues) is _not_
a good way to get your answer, as it is monitored infrequently by a
very small number of people.
When asking a question, it's helpful to provide as much of the
following information as possible (people cannot help you if there's
not enough information in your question):
* the version (or the commit hash if you check out from Git directly) of Google Test you use (Google Test is under active development, so it's possible that your problem has been solved in a later version),
* your operating system,
* the name and version of your compiler,
* the complete command line flags you give to your compiler,
* the complete compiler error messages (if the question is about compilation),
* the _actual_ code (ideally, a minimal but complete program) that has the problem you encounter.
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