[ci] moving linting into small scripts (fixes #5142) (#5809)

.ci/lint-cpp.sh

+#!/bin/sh
+
+echo "running cpplint"
+cpplint \
+    --filter=-build/c++11,-build/include_subdir,-build/header_guard,-whitespace/line_length \
+    --recursive ./src ./include ./R-package ./swig ./tests \
+|| exit -1
+echo "done running cpplint"
+
+echo "running cmakelint"
+cmake_files=$(
+    find . -name CMakeLists.txt -o -path "./cmake/*.cmake" \
+    | grep -v external_libs
+)
+cmakelint \
+    --linelength=120 \
+    --filter=-convention/filename,-package/stdargs,-readability/wonkycase \
+    ${cmake_files} \
+|| exit -1
+echo "done running cmakelint"

.ci/lint-python.sh

+#!/bin/sh
+
+DIR_TO_CHECK=${1}
+
+echo "running flake8"
+flake8 \
+    --ignore=E501,W503 \
+    --exclude=./.nuget,./external_libs,./python-package/build,./python-package/compile \
+    "${DIR_TO_CHECK}" \
+|| exit -1
+echo "done running flake8"
+
+echo "running pydocstyle"
+pydocstyle \
+    --convention=numpy \
+    --add-ignore=D105 \
+    --match-dir="^(?!^external_libs|test|example).*" \
+    --match="(?!^test_|setup).*\.py" \
+    "${DIR_TO_CHECK}" \
+|| exit -1
+echo "done running pydocstyle"
+
+echo "running isort"
+isort \
+    --check-only \
+    "${DIR_TO_CHECK}" \
+|| exit -1
+echo "done running isort"
+
+echo "running mypy"
+mypy \
+    --ignore-missing-imports \
+    --exclude 'build/' \
+    --exclude 'compile/' \
+    --exclude 'docs/' \
+    --exclude 'examples/' \
+    --exclude 'external_libs/' \
+    --exclude 'tests/' \
+    "${DIR_TO_CHECK}/python-package" \
+|| true
+echo "done running mypy"

.ci/test.sh

@@ -66,6 +66,7 @@ if [[ $TASK == "swig" ]]; then
 fi
 
 if [[ $TASK == "lint" ]]; then
+    cd ${BUILD_DIRECTORY}
     conda create -q -y -n $CONDA_ENV \
         ${CONDA_PYTHON_REQUIREMENT} \
         cmakelint \
@@ -77,19 +78,11 @@ if [[ $TASK == "lint" ]]; then
         "r-lintr>=3.0"
     source activate $CONDA_ENV
     echo "Linting Python code"
-    flake8 \
-        --ignore=E501,W503 \
-        --exclude=./.nuget,./external_libs,./python-package/build \
-        . || exit -1
-    pydocstyle --convention=numpy --add-ignore=D105 --match-dir="^(?!^external_libs|test|example).*" --match="(?!^test_|setup).*\.py" . || exit -1
-    isort . --check-only || exit -1
-    mypy --ignore-missing-imports python-package/ || true
+    sh ${BUILD_DIRECTORY}/.ci/lint-python.sh ${BUILD_DIRECTORY} || exit -1
     echo "Linting R code"
     Rscript ${BUILD_DIRECTORY}/.ci/lint_r_code.R ${BUILD_DIRECTORY} || exit -1
     echo "Linting C++ code"
-    cpplint --filter=-build/c++11,-build/include_subdir,-build/header_guard,-whitespace/line_length --recursive ./src ./include ./R-package ./swig ./tests || exit -1
-    cmake_files=$(find . -name CMakeLists.txt -o -path "*/cmake/*.cmake")
-    cmakelint --linelength=120 --filter=-convention/filename,-package/stdargs,-readability/wonkycase ${cmake_files} || exit -1
+    sh ${BUILD_DIRECTORY}/.ci/lint-cpp.sh || exit -1
     exit 0
 fi
 

python-package/README.rst

@@ -252,9 +252,15 @@ Refer to the walk through examples in `Python guide folder <https://github.com/m
 Development Guide
 -----------------
 
-The code style of Python-package follows `PEP 8 <https://www.python.org/dev/peps/pep-0008/>`_. If you would like to make a contribution and not familiar with PEP 8, please check the PEP 8 style guide first. Otherwise, the check won't pass. Only E501 (line too long) and W503 (line break occurred before a binary operator) can be ignored.
+The code style of Python-package follows `PEP 8 <https://www.python.org/dev/peps/pep-0008/>`_.
 
-Documentation strings (docstrings) are written in the NumPy style.
+The package's documentation strings (docstrings) are written in the `numpydoc style <https://numpydoc.readthedocs.io/en/latest/format.html>`_.
+
+To check that a contribution to the package matches its style expectations, run the following from the root of the repo.
+
+.. code:: sh
+
+    sh .ci/lint-python.sh .
 
 .. |License| image:: https://img.shields.io/github/license/microsoft/lightgbm.svg
    :target: https://github.com/microsoft/LightGBM/blob/master/LICENSE