[clang-format] Allow git-clang-format to handle empty extensions.

Most of libc++'s header files don't use extension. This prevents
using git-clang-format on them, which is frustrating.

This patch allows empty extensions to be passed using either
the --extensions option, or the clangformat.extensions git-config
value.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@305437 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/tools/clang-format/git-clang-format b/tools/clang-format/git-clang-format
index 71b9124149fc5b8b187186da8c7beae1c4ff9f06..60cd4fb25b6353b30445380f4d4bcb43ce6af37b 100755 (executable)
--- a/tools/clang-format/git-clang-format
+++ b/tools/clang-format/git-clang-format
@@ -324,6 +324,8 @@ def filter_by_extension(dictionary, allowed_extensions):
   allowed_extensions = frozenset(allowed_extensions)
   for filename in list(dictionary.keys()):
     base_ext = filename.rsplit('.', 1)
+    if len(base_ext) == 1 and '' in allowed_extensions:
+        continue
     if len(base_ext) == 1 or base_ext[1].lower() not in allowed_extensions:
       del dictionary[filename]