[clang] [alpha.webkit.RetainPtrCtorAdoptChecker] Recognize mutableCopy from literal as +1 (PR #132350)

[Ryosuke Niwa via cfe-commits]

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@@ -97,3 +97,13 @@ void create_member_init() {
 RetainPtr<id> return_bridge_cast() {
   return bridge_cast<CFArrayRef, NSArray>(create_cf_array());
 }
+
+void mutable_copy() {
+  RetainPtr<NSMutableDictionary> mutableArray = adoptNS(@{
+    @"Content-Type": @"text/html",
+  }.mutableCopy);
+}
+
+void string_copy(NSString *str) {
+  RetainPtr<NSString> copy = adoptNS(str.copy);
+}
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rniwa wrote:

 There is a test case for `RetainPtr<NSMutableDictionary>` right above it. Or are you saying that we should add a test case which takes NSMutableDictionary* as a function argument?

https://github.com/llvm/llvm-project/pull/132350