[clang-tools-extra] [include-cleaner] Add WalkAST unit tests for Objective-C constructs (PR #220763)

[Nico Weber via cfe-commits]

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@@ -604,6 +606,18 @@ TEST(WalkAST, ObjCImplementationDeclDependsOnInterface) {
            {"-x", "objective-c"});
 }
 
+TEST(WalkAST, ObjCMessageExprFunctionArg) {
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nico wrote:

This test is misnamed, no? I don't see a message expr anywhere in this test.

https://github.com/llvm/llvm-project/pull/220763