[clang] [clang-format] Correctly handle C# attribute on auto property (PR #102921)

[Owen Pan via cfe-commits]

https://github.com/owenca created https://github.com/llvm/llvm-project/pull/102921

Fixes #101487.

>From 5fd35e3d2b9775867a259457879fc7030c901724 Mon Sep 17 00:00:00 2001
From: Owen Pan <owenpiano at gmail.com>
Date: Mon, 12 Aug 2024 08:24:12 -0700
Subject: [PATCH] [clang-format] Correctly handle C# attribute on auto property

Fixes #101487.
---
 clang/lib/Format/UnwrappedLineParser.cpp    | 14 +++++++++-----
 clang/unittests/Format/FormatTestCSharp.cpp | 11 +++++++++++
 2 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/clang/lib/Format/UnwrappedLineParser.cpp b/clang/lib/Format/UnwrappedLineParser.cpp
index 66485c91f64de9..cafbba0a0d0c5b 100644
--- a/clang/lib/Format/UnwrappedLineParser.cpp
+++ b/clang/lib/Format/UnwrappedLineParser.cpp
@@ -2155,12 +2155,16 @@ bool UnwrappedLineParser::tryToParsePropertyAccessor() {
   // Track these as they do not require line breaks to be introduced.
   bool HasSpecialAccessor = false;
   bool IsTrivialPropertyAccessor = true;
+  bool HasAttribute = false;
   while (!eof()) {
-    if (Tok->isAccessSpecifierKeyword() ||
-        Tok->isOneOf(tok::semi, Keywords.kw_internal, Keywords.kw_get,
-                     Keywords.kw_init, Keywords.kw_set)) {
-      if (Tok->isOneOf(Keywords.kw_get, Keywords.kw_init, Keywords.kw_set))
+    if (const bool IsAccessorKeyword =
+            Tok->isOneOf(Keywords.kw_get, Keywords.kw_init, Keywords.kw_set);
+        IsAccessorKeyword || Tok->isAccessSpecifierKeyword() ||
+        Tok->isOneOf(tok::l_square, tok::semi, Keywords.kw_internal)) {
+      if (IsAccessorKeyword)
         HasSpecialAccessor = true;
+      else if (Tok->is(tok::l_square))
+        HasAttribute = true;
       Tok = Tokens->getNextToken();
       continue;
     }
@@ -2169,7 +2173,7 @@ bool UnwrappedLineParser::tryToParsePropertyAccessor() {
     break;
   }
 
-  if (!HasSpecialAccessor) {
+  if (!HasSpecialAccessor || HasAttribute) {
     Tokens->setPosition(StoredPosition);
     return false;
   }
diff --git a/clang/unittests/Format/FormatTestCSharp.cpp b/clang/unittests/Format/FormatTestCSharp.cpp
index 7166e4ec4de30d..3b04238b9b48b0 100644
--- a/clang/unittests/Format/FormatTestCSharp.cpp
+++ b/clang/unittests/Format/FormatTestCSharp.cpp
@@ -1149,6 +1149,17 @@ public class SaleItem
     public decimal Price { get; set; }
 })",
                MicrosoftStyle);
+
+  verifyFormat("internal class Program\n"
+               "{\n"
+               "    bool AutoAllowKnownApps\n"
+               "    {\n"
+               "        get;\n"
+               "        [Simple]\n"
+               "        set;\n"
+               "    }\n"
+               "}",
+               MicrosoftStyle);
 }
 
 TEST_F(FormatTestCSharp, DefaultLiteral) {