From bb708cb4156a6237569ac57636aebcfccdf0242c Mon Sep 17 00:00:00 2001
From: Philipp Wullstein-Kammler <111539239+phiwuu@users.noreply.github.com>
Date: Wed, 4 Dec 2024 10:46:43 +0100
Subject: [PATCH] Add option to pass parameters to clang tidy (#138)

Add new command line argument `--compile-commands` to `lobster-cpp`. Its
value will be forwarded to the call of clang tidy.
---
 CHANGELOG.md             |  5 ++++
 lobster/tools/cpp/cpp.py | 50 +++++++++++++++++++++++++++++-----------
 2 files changed, 41 insertions(+), 14 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 570987c8..b3bca2f8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,11 @@
 
 ### 0.9.20-dev
 
+* Add `--compile-commands` flag to `lobster-cpp`. This allows to specify a path to the
+  compile command database and is effectively a wrapper around the `-p` argument of
+  `clang tidy`. See the official documentation of `clang tidy` for more details on this
+  parameter.
+
 * `lobster-cpptest` writes absolute paths into its `*.lobster` output files instead of
   paths relative to the current working directory.
 
diff --git a/lobster/tools/cpp/cpp.py b/lobster/tools/cpp/cpp.py
index b09aa546..93e22f6f 100755
--- a/lobster/tools/cpp/cpp.py
+++ b/lobster/tools/cpp/cpp.py
@@ -59,6 +59,14 @@ def main():
                     metavar="FILE",
                     help=("use the specified clang-tidy; by default we"
                           " pick the one on PATH"))
+    ap.add_argument("--compile-commands",
+                    metavar="FILE",
+                    default=None,
+                    help=("Path to the compile command database for all targets for "
+                          "'clang tidy', or none to use the default behavior of "
+                          "'clang tidy'. This is equal to calling 'clang tidy' "
+                          "directly with its '-p' option. Refer to its official "
+                          "documentation for more details."))
     ap.add_argument("--out",
                     default=None,
                     help=("write output to this file; otherwise output to"
@@ -83,13 +91,17 @@ def main():
 
     # Test if the clang-tidy can be used
 
-    rv = subprocess.run([os.path.expanduser(options.clang_tidy),
-                         "-checks=-*,lobster-tracing",
-                         "--list-checks"],
-                        stdout=subprocess.PIPE,
-                        stderr=subprocess.PIPE,
-                        encoding="UTF-8",
-                        check=False)
+    rv = subprocess.run(
+        [
+            os.path.expanduser(options.clang_tidy),
+            "-checks=-*,lobster-tracing",
+            "--list-checks",
+        ],
+        stdout=subprocess.PIPE,
+        stderr=subprocess.PIPE,
+        encoding="UTF-8",
+        check=False,
+    )
 
     if "No checks enabled." in rv.stderr:
         print("The provided clang-tidy does include the lobster-tracing check")
@@ -99,13 +111,23 @@ def main():
               "correct binary using the --clang-tidy flag")
         return 1
 
-    rv = subprocess.run([os.path.expanduser(options.clang_tidy),
-                         "-checks=-*,lobster-tracing"] +
-                        file_list,
-                        stdout=subprocess.PIPE,
-                        stderr=subprocess.PIPE,
-                        encoding="UTF-8",
-                        check=False)
+    subprocess_args = [
+        os.path.expanduser(options.clang_tidy),
+        "-checks=-*,lobster-tracing",
+    ]
+    if options.compile_commands:
+        subprocess_args.append("-p")
+        subprocess_args.append(options.compile_commands)
+
+    subprocess_args += file_list
+
+    rv = subprocess.run(
+        subprocess_args,
+        stdout=subprocess.PIPE,
+        stderr=subprocess.PIPE,
+        encoding="UTF-8",
+        check=False,
+    )
 
     if rv.returncode != 0:
         found_reason = False