[clang] [webkit.UncountedLambdaCapturesChecker] Recognize nested protectedThis pattern (PR #126443)

[Ryosuke Niwa via cfe-commits]

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@@ -299,6 +300,29 @@ struct RefCountableWithLambdaCapturingThis {
       return obj->next();
     });
   }
+
+  void callAsyncNoescape([[clang::noescape]] WTF::Function<bool(RefCountable&)>&&);
+  void method_temp_lambda(RefCountable* obj) {
+    callAsyncNoescape([this, otherObj = RefPtr { obj }](auto& obj) {
+      return otherObj == &obj;
+    });
+  }
+
+  void method_nested_lambda() {
+    callAsync([this, protectedThis = Ref { *this }] {
+      callAsync([this, protectedThis = static_cast<const Ref<RefCountableWithLambdaCapturingThis>&&>(protectedThis)] {
+        nonTrivial();
+      });
+    });
+  }
+
+  void method_nested_lambda2() {
+    callAsync([this, protectedThis = RefPtr { this }] {
+      callAsync([this, protectedThis = static_cast<const Ref<RefCountableWithLambdaCapturingThis>&&>(*protectedThis)] {
+        nonTrivial();
+      });
+    });
+  }
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rniwa wrote:

Added a test case.

https://github.com/llvm/llvm-project/pull/126443