Support clang-tidy (early PR for review)

[peakschris]

Support clang-tidy for linting of C++ code.

Inspired by and containing some code from bazel_clang_tidy repo. This integration has been discussed by maintainers of both repos in erenon/bazel_clang_tidy#35.

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Changes are visible to end-users: yes

• Searched for relevant documentation and updated as needed: yes
• Breaking change (forces users to change their own code or config): no
• Suggested release notes appear below: todo

Test plan

Needs discussion

• Covered by existing test cases
• New test cases added
• Manual testing; please provide instructions so we can reproduce:

Code used from bazel_clang_tidy repo

Two helper functions toolchain_flags and safe_flags have been copied from bazel_clang_tidy and used in clang_tidy.bzl. Also, some lines in get_args are copied from bazel_clang_tidy. bazel_clang_tidy was also a very helpful learning tool in how to integrate clang-tidy into a bazel aspect. The rest of the code is implemented by following existing rules_lint code such as ruff.bzl and eslint.bzl.

Release notes (early input, will reformat)

• warning that git bash does not handle arguments correctly and --fix may have issues on Windows. msys64 bash (already recommended by Bazel is ok).

[CLAassistant]

All committers have signed the CLA.

[peakschris]

Known issues with this MR:

1. ./lint.sh --fix //src/cpp/main/... fails on linux with:

ERROR: /apps/browchri/rules_lint/example/src/cpp/main/BUILD:3:11: output 'src/cpp/main/cpp/main/hello-greet.cc.AspectRulesLintClangT                                                idy.report' was not created
ERROR: /apps/browchri/rules_lint/example/src/cpp/main/BUILD:3:11: output 'src/cpp/main/cpp/main/hello-greet.cc.AspectRulesLintClangT                                                idy.exit_code' was not created
ERROR: /apps/browchri/rules_lint/example/src/cpp/main/BUILD:3:11: Linting //src/cpp/main:hello-greet with clang-tidy failed: not all                                                 outputs were created or valid

2. Not sure if my approach to handle multiple srcs whilst clang-tidy only handles one is valid or optimal.
3. Would like guidance on refactoring/adding APIs to replace my copies of report_files and patch_file that allow per-file reports/patches
4. Could use guidance on how to construct a relative filename for these report files for files that are in subdirectories.

Known issues with repo on windows, not related to this MR:

1. bash lint.sh --fix //src/cpp/main/... fails on windows with missing node.bat wrapper error from rules_js

ERROR: D:/workdir/rules_lint3/example/src/cpp/main/BUILD:10:10: Linting //src/cpp/main:hello-world with clang-tidy failed: (Exit 1): patcher.bat failed: error executing AspectRulesLintClangTidy command (from target //src/cpp/main:hello-world) bazel-out\x64_windows-opt-exec-ST-13d3ddad9198\bin\external\aspect_rules_lint~\lint\private\patcher_\patcher.bat bazel-out/x64_windows-fastbuild/bin/src/cpp/main/_hello-world.patch_cfg
FATAL: aspect_rules_js[js_binary]: node wrapper '/d/udu/b/l2x2bhay/execroot/_main/./external/aspect_rules_lint~/lint/private/patcher_node_bin/node.bat' not found

2. Various issues with support for windows in the examples repo; workarounds applied by workaround_windows.bat but would guidance on correcting these properly.

[alexeagle]

Wow, this looks like a great start. I'll find some more time to comb through the details soon.

[alexeagle]

Interesting, why is clang-tidy the only tool that needs to produce different number of reports? I think this will break the API this ruleset exposes to surrounding tools that want to present the results - they assume there is a report for each action. Maybe we can merge them?

[peakschris]

I'm replacing this PR with #287, addressing the comment about report files and cleaning up the commit history.