[clang-tools-extra] [clangd] Update XRefs to support overriden ObjC methods (PR #127109)

[kadir çetinkaya via cfe-commits]

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@@ -430,6 +439,22 @@ locateASTReferent(SourceLocation CurLoc, const syntax::Token *TouchedIdentifier,
         continue;
       }
     }
+    // Special case: - (void)^method; should jump to all overrides. Note that an
+    // Objective-C method can override a parent class or protocol.
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kadircet wrote:

i think it's worthwhile to also add a test to check we don't return overridden methods when calling xrefs on usage of the method.

https://github.com/llvm/llvm-project/pull/127109