fix: clang-tidy lint step fails when no csrc files change

[andrewwhitecdw]

This PR addresses the following issue in .github/workflows/lint.yml: clang-tidy lint step fails when no csrc files change.

Changes

• .github/workflows/lint.yml: clang-tidy lint step fails when no csrc files change.

Details

--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@@ -1,1 +1,4 @@
-          git --no-pager diff --diff-filter=d --name-only $head_commit | grep -e "csrc/.*\.cpp" -e "csrc/.*\.h" | xargs lintrunner --take CLANGTIDY --force-color
+          files=$(git --no-pager diff --diff-filter=d --name-only $head_commit | grep -e "csrc/.*\.cpp" -e "csrc/.*\.h" || true)
+          if [ -n "$files" ]; then
+            echo "$files" | xargs -r lintrunner --take CLANGTIDY --force-color
+          fi

Tests

• tests/test_repo_config.py

diff --git a/tests/test_repo_config.py b/tests/test_repo_config.py
new file mode 100644
--- /dev/null
+++ b/tests/test_repo_config.py
@@ -0,0 +1,39 @@
+import unittest
+from pathlib import Path
+
+
+REPO_ROOT = Path(__file__).resolve().parent.parent
+
+
+class TestGitignore(unittest.TestCase):
+    def test_nvfuser_common_lib_ignored(self):
+        gitignore = (REPO_ROOT / ".gitignore").read_text()
+        self.assertIn("nvfuser_common/lib", gitignore)
+        self.assertNotIn("nvfuser_comon/lib", gitignore)
+
+
+class TestLintWorkflow(unittest.TestCase):
+    def test_clang_tidy_step_handles_empty_file_list(self):
+        workflow = (REPO_ROOT / ".github" / "workflows" / "lint.yml").read_text()
+        self.assertIn('if [ -n "$files" ]', workflow)
+        self.assertIn("xargs -r", workflow)
+        self.assertNotIn(
+            'git --no-pager diff --diff-filter=d --name-only $head_commit | grep -e "csrc/.*\.cpp" -e "csrc/.*\.h" | xargs lintrunner --take CLANGTIDY --force-color',
+            workflow,
+        )
+
+
+if __name__ == "__main__":
+    unittest.main()

[greptile-apps]

Greptile Summary

This PR prevents the clang-tidy workflow from invoking lintrunner when no matching C/C++ files changed.

• Captures matching paths before invoking lintrunner.
• Skips invocation for an empty file list.
• Adds GNU xargs' no-run-if-empty option as an additional safeguard.

Confidence Score: 4/5

The PR appears safe to merge, with a non-blocking concern that file-discovery errors can now be silently treated as an empty diff.

The empty-input failure is fixed, but the broad error suppression can allow clang-tidy to be skipped when changed-file discovery itself fails.

Files Needing Attention: .github/workflows/lint.yml

Important Files Changed

Filename	Overview
.github/workflows/lint.yml	Correctly avoids an empty lintrunner invocation, but broadly suppresses failures from the changed-file discovery pipeline.

_{Reviews (1): Last reviewed commit: "fix: clang-tidy lint step fails when no ..." | Re-trigger Greptile}

[greptile-apps]

Broad pipeline error suppression

The trailing || true treats every file-discovery failure as an empty result, so an unavailable revision or repository read error skips clang-tidy and lets the step succeed instead of exposing the underlying failure.