[clang] [clang-format] Fix a bug in annotating TrailingReturnArrow (PR #69249)

[Owen Pan via cfe-commits]

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@@ -3497,6 +3497,15 @@ void TokenAnnotator::calculateFormattingInformation(AnnotatedLine &Line) const {
           Tok->setType(TT_TrailingReturnArrow);
           break;
         }
+        if (Tok->isNot(TT_TrailingAnnotation))
----------------
owenca wrote:

Before: look for _any_ arrow after the `r_paren` of the function declaration.
Now: look for any arrow _except_ when inside the parentheses after a `TT_TrailingAnnotation`.

The case where `Next` is `nullptr` is handled by the condition of the `for` loop whereas any tokens (including non-`l_parens`) before a `TT_TrailingAnnotation` should be skipped as before.


https://github.com/llvm/llvm-project/pull/69249