[clang] d9567ba - Fix extraneous whitespace addition in line comments on clang-format directives

[Marek Kurdej via cfe-commits]

Author: Luis Penagos
Date: 2022-02-20T21:53:50+01:00
New Revision: d9567babef302cfd7e827df64138151ba2614b83

URL: https://github.com/llvm/llvm-project/commit/d9567babef302cfd7e827df64138151ba2614b83
DIFF: https://github.com/llvm/llvm-project/commit/d9567babef302cfd7e827df64138151ba2614b83.diff

LOG: Fix extraneous whitespace addition in line comments on clang-format directives

Fixes https://github.com/llvm/llvm-project/issues/53844.
I believe this regression was caused by not accounting for clang-format directives in https://reviews.llvm.org/D92257.

Reviewed By: HazardyKnusperkeks, curdeius

Differential Revision: https://reviews.llvm.org/D120188

Added: 
    

Modified: 
    clang/lib/Format/BreakableToken.cpp
    clang/unittests/Format/FormatTestComments.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/Format/BreakableToken.cpp b/clang/lib/Format/BreakableToken.cpp
index 5138c7cd42cc6..967ddeb82383a 100644
--- a/clang/lib/Format/BreakableToken.cpp
+++ b/clang/lib/Format/BreakableToken.cpp
@@ -815,10 +815,13 @@ BreakableLineCommentSection::BreakableLineCommentSection(
 
         assert(Lines[i].size() > IndentPrefix.size());
         const auto FirstNonSpace = Lines[i][IndentPrefix.size()];
-        const auto AllowsSpaceChange =
-            SpacesInPrefix != 0 ||
-            (!NoSpaceBeforeFirstCommentChar() ||
-             (FirstNonSpace == '}' && FirstLineSpaceChange != 0));
+        const bool IsFormatComment = LineTok && switchesFormatting(*LineTok);
+        const bool LineRequiresLeadingSpace =
+            !NoSpaceBeforeFirstCommentChar() ||
+            (FirstNonSpace == '}' && FirstLineSpaceChange != 0);
+        const bool AllowsSpaceChange =
+            !IsFormatComment &&
+            (SpacesInPrefix != 0 || LineRequiresLeadingSpace);
 
         if (PrefixSpaceChange[i] > 0 && AllowsSpaceChange) {
           Prefix[i] = IndentPrefix.str();

diff  --git a/clang/unittests/Format/FormatTestComments.cpp b/clang/unittests/Format/FormatTestComments.cpp
index c988a2869e568..f83ffb393ac2f 100644
--- a/clang/unittests/Format/FormatTestComments.cpp
+++ b/clang/unittests/Format/FormatTestComments.cpp
@@ -91,6 +91,11 @@ TEST_F(FormatTestComments, UnderstandsSingleLineComments) {
                "// line 2\n"
                "void f() {}\n");
 
+  EXPECT_EQ("// comment\n"
+            "// clang-format on\n",
+            format("//comment\n"
+                   "// clang-format on\n"));
+
   verifyFormat("void f() {\n"
                "  // Doesn't do anything\n"
                "}");