message: add docs for cpp tests requiring built libraries
  add jcwchen change for windows
  Update docs/CONTRIBUTING.md
diff: @@ -86,7 +86,21 @@ python onnx\backend\test\stat_coverage.py
  Some functionalities are tested with googletest. Those tests are listed in `test/cpp`, and include tests for shape inference, data propagation, parser, and others.
  -To run them, first build ONNX with `-DONNX_BUILD_TESTS=1` or `ONNX_BUILD_TESTS=1 pip install -e .` and then run `.setuptools-cmake-build/onnx_gtests`.
  +To run them, first build ONNX with `-DONNX_BUILD_TESTS=1` or `ONNX_BUILD_TESTS=1 pip install -e .`.
  +
  +### Linux and MacOS
  +The cpp tests require dynamically linking to built libraries.
  +
  +```bash
  +export LD_LIBRARY_PATH="./.setuptools-cmake-build/:$LD_LIBRARY_PATH"
  +.setuptools-cmake-build/onnx_gtests
  +```
  +
  +### Windows
  +```bat
  +# If you set DEBUG=1, use `.setuptools-cmake-build\Debug\onnx_gtests.exe` instead
  +.setuptools-cmake-build\Release\onnx_gtests.exe
  +```
  # Static typing (mypy)
  