clang-tidy: fix the fact that we are not linting headers properly

This, however, took fixing a pile of lints that we predictably missed
because of this bug.

Change-Id: I92c36feb4a03f62bc594c2051c7bd7418d13fb08

1 files changed, 89 insertions, 0 deletions

diff --git a/meson/clang-tidy/clang-tidy-runner.py b/meson/clang-tidy/clang-tidy-runner.py
new file mode 100755
index 000000000..c36e66b41
--- /dev/null
+++ b/meson/clang-tidy/clang-tidy-runner.py
@@ -0,0 +1,89 @@
+#!/usr/bin/env python3
+"""
+Runs run-clang-tidy. A bit meta. Maybe it will replace run-clang-tidy one day
+because the run-clang-tidy UX is so questionable.
+"""
+
+# I hereby dedicate this script to fuck you meson.
+# I cannot simply write my code to invoke a subprocess in a meson file because
+# Meson corrupts backslashes in command line args to subprocesses.
+# This is allegedly for "Windows support", but last time I checked Windows
+# neither needs nor wants you to corrupt its command lines.
+# https://github.com/mesonbuild/meson/issues/1564
+
+import multiprocessing
+import subprocess
+import os
+import sys
+from pathlib import Path
+
+
+def default_concurrency():
+    return min(multiprocessing.cpu_count(),
+               int(os.environ.get("NIX_BUILD_CORES", "16")))
+
+
+def go(exe: str, plugin_path: Path, compile_commands_json_dir: Path, jobs: int,
+       paths: list[Path], werror: bool, fix: bool):
+    args = [
+        # XXX: This explicitly invokes it with python because of a nixpkgs bug
+        # where clang-unwrapped does not patch interpreters in run-clang-tidy.
+        # However, making clang-unwrapped depend on python is also silly, so idk.
+        sys.executable,
+        exe,
+        '-quiet',
+        '-load',
+        plugin_path,
+        '-p',
+        compile_commands_json_dir,
+        '-j',
+        str(jobs),
+        '-header-filter',
+        r'src/[^/]+/.*\.hh'
+    ]
+    if werror:
+        args += ['-warnings-as-errors', '*']
+    if fix:
+        args += ['-fix']
+    args += ['--']
+    args += paths
+    os.execvp(sys.executable, args)
+
+
+def main():
+    import argparse
+
+    ap = argparse.ArgumentParser(description='Runs run-clang-tidy for you')
+    ap.add_argument('--jobs',
+                    '-j',
+                    type=int,
+                    default=default_concurrency(),
+                    help='Parallel linting jobs to run')
+    ap.add_argument('--plugin-path',
+                    type=Path,
+                    help='Path to the Lix clang-tidy plugin')
+    # FIXME: maybe we should integrate this so it just fixes the compdb for you and throws it in a tempdir?
+    ap.add_argument(
+        '--compdb-path',
+        type=Path,
+        help=
+        'Path to the directory containing the fixed-up compilation database from clean_compdb'
+    )
+    ap.add_argument('--werror',
+                    action='store_true',
+                    help='Warnings get turned into errors')
+    ap.add_argument('--fix',
+                    action='store_true',
+                    help='Apply fixes for warnings')
+    ap.add_argument('--run-clang-tidy-path',
+                    default='run-clang-tidy',
+                    help='Path to run-clang-tidy')
+    ap.add_argument('paths', nargs='*', help='Source paths to check')
+    args = ap.parse_args()
+
+    go(args.run_clang_tidy_path, args.plugin_path, args.compdb_path, args.jobs,
+       args.paths, args.werror, args.fix)
+
+
+if __name__ == '__main__':
+    main()