[clang-tools-extra] [clang-tidy][C++20] Add support for Initialization Forwarding in structs and Nested Objects within modernize-use-emplace (PR #131969)

[Baranov Victor via cfe-commits]

================
@@ -1434,3 +1436,33 @@ void testWithPointerTypes() {
   // CHECK-MESSAGES: :[[@LINE-1]]:15: warning: unnecessary temporary object created while calling emplace
   // CHECK-FIXES: sp->emplace();
 }
+
+namespace GH1225740 {
+
+void CXX20testBracedInitTemporaries(){
+
+  std::vector<NonTrivialNoCtor> v1;
+
+  v1.push_back(NonTrivialNoCtor{""});
+  // CHECK-MESSAGES-CPP20: :[[@LINE-1]]:6: warning: use emplace_back instead of push_back
+  // CHECK-FIXES-CPP20: v1.emplace_back("");
+  v1.push_back({""});
+  // CHECK-MESSAGES-CPP20: :[[@LINE-1]]:6: warning: use emplace_back instead of push_back
+  // CHECK-FIXES-CPP20: v1.emplace_back("");
+  v1.push_back(NonTrivialNoCtor{InnerType{""}});
+  // CHECK-MESSAGES-CPP20: :[[@LINE-1]]:6: warning: use emplace_back instead of push_back
+  // CHECK-FIXES-CPP20: v1.emplace_back(InnerType{""});
+  v1.push_back({InnerType{""}});
+  // CHECK-MESSAGES-CPP20: :[[@LINE-1]]:6: warning: use emplace_back instead of push_back
+  // CHECK-FIXES-CPP20: v1.emplace_back(InnerType{""});
+
+  std::vector<NonTrivialWithVector> v2;
+
+  v2.push_back(NonTrivialWithVector{std::vector<int>{0}});
+  // CHECK-MESSAGES-CPP20: :[[@LINE-1]]:6: warning: use emplace_back instead of push_back
+  // CHECK-FIXES-CPP20: v2.emplace_back(std::vector<int>{0});
+  v2.push_back({std::vector<int>{0}});
+  // CHECK-MESSAGES-CPP20: :[[@LINE-1]]:6: warning: use emplace_back instead of push_back
+  // CHECK-FIXES-CPP20: v2.emplace_back(std::vector<int>{0});
+  }
----------------
vbvictor wrote:

```suggestion
}
```

https://github.com/llvm/llvm-project/pull/131969