[clang-tools-extra] [run-clang-tidy] Add option -export-directory (PR #69453)

[Amadeus Gebauer via cfe-commits]

https://github.com/amgebauer created https://github.com/llvm/llvm-project/pull/69453

Adding an additional parameter to run_clang_tidy.py to accept a directory where the clang-tidy fixes are saved to. This directory can then be used to run `clang-apply-replacements`.

>From fd908df80b14933c849e498769cff6152276c2c3 Mon Sep 17 00:00:00 2001
From: Amadeus Gebauer <amadeus.gebauer at tum.de>
Date: Wed, 18 Oct 2023 14:02:44 +0200
Subject: [PATCH] [run-clang-tidy] Add option -export-directory

---
 .../clang-tidy/tool/run-clang-tidy.py             | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/clang-tools-extra/clang-tidy/tool/run-clang-tidy.py b/clang-tools-extra/clang-tidy/tool/run-clang-tidy.py
index 312d9241cfa57c5..b8d482809e293a5 100755
--- a/clang-tools-extra/clang-tidy/tool/run-clang-tidy.py
+++ b/clang-tools-extra/clang-tidy/tool/run-clang-tidy.py
@@ -372,6 +372,11 @@ def main():
         default=None,
         help="Upgrades warnings to errors. Same format as " "'-checks'",
     )
+    parser.add_argument(
+        "-export-directory",
+        default=None,
+        help="Path to the export directory. Within this directory, a file with the fixes will be created for every compilation unit.",
+    )
     args = parser.parse_args()
 
     db_path = "compile_commands.json"
@@ -384,15 +389,17 @@ def main():
 
     clang_tidy_binary = find_binary(args.clang_tidy_binary, "clang-tidy", build_path)
 
-    tmpdir = None
     if args.fix:
         clang_apply_replacements_binary = find_binary(
             args.clang_apply_replacements_binary, "clang-apply-replacements", build_path
         )
 
-    if args.fix or (yaml and args.export_fixes):
+    tmpdir = args.export_directory
+    if tmpdir is None and (args.fix or (yaml and args.export_fixes)):
         tmpdir = tempfile.mkdtemp()
 
+    delete_temporary_directory = args.export_directory is None and tmpdir is not None
+
     try:
         invocation = get_tidy_invocation(
             "",
@@ -474,7 +481,7 @@ def main():
         # This is a sad hack. Unfortunately subprocess goes
         # bonkers with ctrl-c and we start forking merrily.
         print("\nCtrl-C detected, goodbye.")
-        if tmpdir:
+        if tmpdir and delete_temporary_directory:
             shutil.rmtree(tmpdir)
         os.kill(0, 9)
 
@@ -496,7 +503,7 @@ def main():
             traceback.print_exc()
             return_code = 1
 
-    if tmpdir:
+    if tmpdir and delete_temporary_directory:
         shutil.rmtree(tmpdir)
     sys.exit(return_code)