[clang] [clang-format] Handle C++ Core Guidelines suppression tags (PR #86458)

[Owen Pan via cfe-commits]

https://github.com/owenca created https://github.com/llvm/llvm-project/pull/86458

Fixes #86451.

>From 4149b046f97a4416041e2cd3fe5f134abed2f5d9 Mon Sep 17 00:00:00 2001
From: Owen Pan <owenpiano at gmail.com>
Date: Sun, 24 Mar 2024 16:06:14 -0700
Subject: [PATCH] [clang-format] Handle C++ Core Guidelines suppression tags

Fixes #86451.
---
 clang/lib/Format/TokenAnnotator.cpp   | 4 ++++
 clang/unittests/Format/FormatTest.cpp | 1 +
 2 files changed, 5 insertions(+)

diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
index 4c83a7a3a323be..b9144cf55452e2 100644
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -4827,6 +4827,10 @@ bool TokenAnnotator::spaceRequiredBefore(const AnnotatedLine &Line,
         Right.is(TT_TemplateOpener)) {
       return true;
     }
+    if (Left.is(tok::identifier) && Right.is(tok::numeric_constant) &&
+        Right.TokenText[0] == '.') {
+      return false;
+    }
   } else if (Style.isProto()) {
     if (Right.is(tok::period) &&
         Left.isOneOf(Keywords.kw_optional, Keywords.kw_required,
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index 03005384a6f667..2f9ff43b9fa5bc 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -12075,6 +12075,7 @@ TEST_F(FormatTest, UnderstandsSquareAttributes) {
   verifyFormat("SomeType s [[gnu::unused]] (InitValue);");
   verifyFormat("SomeType s [[using gnu: unused]] (InitValue);");
   verifyFormat("[[gsl::suppress(\"clang-tidy-check-name\")]] void f() {}");
+  verifyFormat("[[suppress(type.5)]] int uninitialized_on_purpose;");
   verifyFormat("void f() [[deprecated(\"so sorry\")]];");
   verifyFormat("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\n"
                "    [[unused]] aaaaaaaaaaaaaaaaaaaaaaa(int i);");