From b21709bde49531be20ec9602e7e553c1938d3cf7 Mon Sep 17 00:00:00 2001
From: Daniel Moody <dmoody256@gmail.com>
Date: Mon, 23 Jun 2025 15:41:04 -0500
Subject: [PATCH] SERVER-106576 vscode clang tidy falls back to direct clang
 tidy command for headers (#37632)

GitOrigin-RevId: 7805f38151c1bfb70ccdc1881b33cc5ce9c2a789
---
 buildscripts/clang_tidy_vscode.py | 41 ++++++++++++++++++++-----------
 1 file changed, 27 insertions(+), 14 deletions(-)

diff --git a/buildscripts/clang_tidy_vscode.py b/buildscripts/clang_tidy_vscode.py
index 38d4f086226..3267385442d 100755
--- a/buildscripts/clang_tidy_vscode.py
+++ b/buildscripts/clang_tidy_vscode.py
@@ -96,10 +96,11 @@ def main():
         with open(".mongo_checks_module_path") as f:
             checks_so = f.read().strip()
 
-    if os.path.isfile(checks_so):
+    if checks_so and os.path.isfile(checks_so):
         clang_tidy_cmd += [f"-load={checks_so}"]
     else:
         print("ERROR: failed to find mongo tidy checks, run `bazel build compiledb'")
+        sys.exit(1)
 
     files_to_check = []
     other_args = []
@@ -142,21 +143,33 @@ def main():
             except ValueError:
                 pass
             break
-    cfg_dir = pathlib.Path().home() / ".cltcache"
-    cfg_dir.mkdir(parents=True, exist_ok=True)
-    with open(cfg_dir / "cltcache.cfg", "w") as f:
-        f.write(CLTCONFIG % executable)
 
-    full_cmd = (
-        [sys.executable, cltcache_path]
-        + clang_tidy_cmd
-        + files_to_check
-        + other_args
-        + ["--"]
-        + compile_args
-    )
+    # found a cpp file entry with exact compile args, cache it
+    if compile_args:
+        cfg_dir = pathlib.Path().home() / ".cltcache"
+        cfg_dir.mkdir(parents=True, exist_ok=True)
+
+        conf_file = cfg_dir / "cltcache.cfg"
+        new_content = CLTCONFIG % executable
+
+        if not conf_file.exists() or conf_file.read_text() != new_content:
+            conf_file.write_text(new_content)
+
+        full_cmd = (
+            [sys.executable, cltcache_path]
+            + clang_tidy_cmd
+            + files_to_check
+            + other_args
+            + ["--"]
+            + compile_args
+        )
+
+        proc = subprocess.run(full_cmd, capture_output=True)
+
+    # probably a header, skip caching and let clang-tidy do its thing:
+    else:
+        proc = subprocess.run(clang_tidy_cmd + files_to_check + other_args, capture_output=True)
 
-    proc = subprocess.run(full_cmd, capture_output=True)
     sys.stdout.buffer.write(proc.stdout)
     sys.stderr.buffer.write(proc.stderr)
     return proc.returncode