[clang-tools-extra] [clang-tidy] add new check readability-enum-initial-value (PR #86129)

[Piotr Zegar via cfe-commits]

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@@ -0,0 +1,31 @@
+//===--- EnumInitialValueCheck.h - clang-tidy -------------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_ENUMINITIALVALUECHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_ENUMINITIALVALUECHECK_H
+
+#include "../ClangTidyCheck.h"
+
+namespace clang::tidy::readability {
+
+/// Detects explicit initialization of a part of enumerators in an enumeration,
+/// and relying on compiler to initialize the others.
+///
+/// For the user-facing documentation see:
+/// http://clang.llvm.org/extra/clang-tidy/checks/readability/enum-initial-value.html
+class EnumInitialValueCheck : public ClangTidyCheck {
+public:
+  EnumInitialValueCheck(StringRef Name, ClangTidyContext *Context)
+      : ClangTidyCheck(Name, Context) {}
+  void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+  void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
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PiotrZSL wrote:

Exclude implicit code here via TK_IgnoreUnlessSpelledInSource.

https://github.com/llvm/llvm-project/pull/86129