Tools for Code Style Compliance

This section provides a list of tools that some have found useful for ensuring their code abides by Drake’s coding style. The list is by no means comprehensive. If your favorite tools or methodologies are not listed, we would be delighted to learn about them. Please document your trick and submit a pull request!

Automated style checks

Code style tests are run by default during bazel test and the results are cached so that only edited files are re-checked. In other words, no special action is required by a developer.

However, you may still invoke code style checks directly if desired, as follows:

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cd /path/to/drake
bazel test --config lint //...         # Only run style checks; don't build or test anything else.
bazel test --config lint //common/...  # Check common/ and its child subdirectories.

User manuals for the style-checking tools are as follows:

• C/C++: See the cpplint USAGE string at https://github.com/google/styleguide/blob/gh-pages/cpplint/cpplint.py.
  • In particular, note the // NOLINT(foo/bar) syntax to disable a warning.
• Python: See the pycodestyle manual at http://pycodestyle.readthedocs.io/en/latest/intro.html.
  • The syntax # noqa can be used to quiet the warning about an overly-long line.
• Bazel: Uses both pycodestyle like Python, and also buildifier.

Manual style fixups

C/C++: Clang-Format

The Mandatory platform specific instructions install Drake’s required version of clang-format, depending on the platform (macOS or Ubuntu).

To run clang-format:

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# For development on macOS:
/usr/local/opt/llvm@9/bin/clang-format -i -style=file [file name]

# For development on Ubuntu:
clang-format-9 -i -style=file [file name]