[clang-tools-extra] Adding an initial version of the "Initialized Class Members" checker. (PR #65189)

[Gábor Horváth via cfe-commits]

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@@ -0,0 +1,105 @@
+//===--- CppInitClassMembersCheck.cpp - clang-tidy ------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include <string>
+
+#include "CppInitClassMembersCheck.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/Decl.h"
+#include "clang/AST/Type.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/ASTMatchers/ASTMatchers.h"
+#include "clang/ASTMatchers/ASTMatchersMacros.h"
+#include "clang/Basic/Diagnostic.h"
+#include "clang/Basic/LLVM.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::google {
+
+namespace {
+
+// Matches records that have a default constructor.
+AST_MATCHER(CXXRecordDecl, hasDefaultConstructor) {
+  return Node.hasDefaultConstructor();
+}
+
+// Returns the names of `Fields` in a comma separated string.
+std::string
+toCommaSeparatedString(const SmallVector<const FieldDecl *, 16> &Fields) {
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Xazax-hun wrote:

Consider taking arguments using `llvm::ArrayRef`, that should work with a wide variety of containers at the callers.

https://github.com/llvm/llvm-project/pull/65189