Ability to optionally depend on Abseil plus upstream of 183716547

BUILD.bazel

@@ -46,6 +46,12 @@ config_setting(
     values = {"cpu": "x64_windows_msvc"},
 )
 
+config_setting(
+    name = "has_absl",
+    values = {"define": "absl=1"},
+)
+
+
 # Google Test including Google Mock
 cc_library(
     name = "gtest",
@@ -88,6 +94,20 @@ cc_library(
             "-pthread",
         ],
     }),
+    defines = select ({
+        ":has_absl": [
+        "GTEST_HAS_ABSL=1",
+        ],
+        "//conditions:default": [],
+    }
+    ),
+    deps = select ({
+        ":has_absl": [
+        "@com_google_absl//absl/types:optional",
+        ],
+        "//conditions:default": [],
+    }
+    )
 )
 
 cc_library(

WORKSPACE

 workspace(name = "com_google_googletest")
+
+# Abseil
+http_archive(
+     name = "com_google_absl",
+     urls = ["https://github.com/abseil/abseil-cpp/archive/master.zip"],
+     strip_prefix = "abseil-cpp-master",
+)

googletest/include/gtest/gtest-printers.h

@@ -46,6 +46,10 @@
 //   2. operator<<(ostream&, const T&) defined in either foo or the
 //      global namespace.
 //
+// However if T is an STL-style container then it is printed element-wise
+// unless foo::PrintTo(const T&, ostream*) is defined. Note that
+// operator<<() is ignored for container types.
+//
 // If none of the above is defined, it will print the debug string of
 // the value if it is a protocol buffer, or print the raw bytes in the
 // value otherwise.
@@ -107,6 +111,10 @@
 # include <tuple>
 #endif
 
+#if GTEST_HAS_ABSL
+#include "absl/types/optional.h"
+#endif  // GTEST_HAS_ABSL
+
 namespace testing {
 
 // Definitions in the 'internal' and 'internal2' name spaces are
@@ -722,6 +730,26 @@ class UniversalPrinter {
   GTEST_DISABLE_MSC_WARNINGS_POP_()
 };
 
+#if GTEST_HAS_ABSL
+
+// Printer for absl::optional
+
+template <typename T>
+class UniversalPrinter<::absl::optional<T>> {
+ public:
+  static void Print(const ::absl::optional<T>& value, ::std::ostream* os) {
+    *os << '(';
+    if (!value) {
+      *os << "nullopt";
+    } else {
+      UniversalPrint(*value, os);
+    }
+    *os << ')';
+  }
+};
+
+#endif  // GTEST_HAS_ABSL
+
 // UniversalPrintArray(begin, len, os) prints an array of 'len'
 // elements, starting at address 'begin'.
 template <typename T>

googletest/test/gtest-printers_test.cc

@@ -1765,5 +1765,17 @@ TEST(UniversalTersePrintTupleFieldsToStringsTestWithStd, PrintsTersely) {
 
 #endif  // GTEST_HAS_STD_TUPLE_
 
+#if GTEST_HAS_ABSL
+
+TEST(PrintOptionalTest, Basic) {
+  absl::optional<int> value;
+  EXPECT_EQ("(nullopt)", PrintToString(value));
+  value = {7};
+  EXPECT_EQ("(7)", PrintToString(value));
+  EXPECT_EQ("(1.1)", PrintToString(absl::optional<double>{1.1}));
+  EXPECT_EQ("(\"A\")", PrintToString(absl::optional<std::string>{"A"}));
+}
+#endif  // GTEST_HAS_ABSL
+
 }  // namespace gtest_printers_test
 }  // namespace testing