[clang-format] [PR45942] [[nodiscard]] causes && to be miss interpreted as BinaryOper...

Summary:
https://bugs.llvm.org/show_bug.cgi?id=45942

With Chromium style (although that is not important) its just it defines PointerAligmment: Left

The following arguments `S&&` are formatted differently depending on if the class has an attribute between it and the class identifier

```
class S {
  S(S&&) = default;
};

class [[nodiscard]] S {
  S(S &&) = default;
};
```

The prescense of [[nodiscard]] between the `class/struct` and the `{` causes the `{` to be incorrectly seen as a `TT_FunctionLBrace` which in turn transforms all the && to be `TT_BinaryOperators` rather than `TT_PointerOrReference`, as binary operators other spacing rules come into play causing a miss format

This revision resolves this by allowing the parseRecord to consider the [[nodisscard]]

Reviewed By: Abpostelnicu

Subscribers: cfe-commits

Tags: #clang, #clang-format

Differential Revision: https://reviews.llvm.org/D80008

diff --git a/clang/lib/Format/UnwrappedLineParser.cpp b/clang/lib/Format/UnwrappedLineParser.cpp
index 58206a0..08c634a 100644 (file)
--- a/clang/lib/Format/UnwrappedLineParser.cpp
+++ b/clang/lib/Format/UnwrappedLineParser.cpp
@@ -2404,7 +2404,7 @@ void UnwrappedLineParser::parseRecord(bool ParseAsExpr) {
   // An [[attribute]] can be before the identifier.
   while (FormatTok->isOneOf(tok::identifier, tok::coloncolon, tok::hashhash,
                             tok::kw___attribute, tok::kw___declspec,
-                            tok::kw_alignas, TT_AttributeSquare) ||
+                            tok::kw_alignas, tok::l_square, tok::r_square) ||
          ((Style.Language == FormatStyle::LK_Java ||
            Style.Language == FormatStyle::LK_JavaScript) &&
           FormatTok->isOneOf(tok::period, tok::comma))) {

diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index a421ca9..d128f4b 100644 (file)
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -8014,6 +8014,30 @@ TEST_F(FormatTest, UnderstandsSquareAttributes) {
                MultiLineFunctions);
 }
 
+TEST_F(FormatTest, AttributeClass) {
+  FormatStyle Style = getChromiumStyle(FormatStyle::LK_Cpp);
+  verifyFormat("class S {\n"
+               "  S(S&&) = default;\n"
+               "};",
+               Style);
+  verifyFormat("class [[nodiscard]] S {\n"
+               "  S(S&&) = default;\n"
+               "};",
+               Style);
+  verifyFormat("class __attribute((maybeunused)) S {\n"
+               "  S(S&&) = default;\n"
+               "};",
+               Style);
+  verifyFormat("struct S {\n"
+               "  S(S&&) = default;\n"
+               "};",
+               Style);
+  verifyFormat("struct [[nodiscard]] S {\n"
+               "  S(S&&) = default;\n"
+               "};",
+               Style);
+}
+
 TEST_F(FormatTest, AttributePenaltyBreaking) {
   FormatStyle Style = getLLVMStyle();
   verifyFormat("void ABCDEFGH::ABCDEFGHIJKLMN(\n"