[clang-tools-extra] [clang-tidy] Add `modernize-use-if-consteval` check (PR #189743)

[Daniil Dudkin via cfe-commits]

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@@ -0,0 +1,147 @@
+//===----------------------------------------------------------------------===//
+//
+// 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 "UseIfConstevalCheck.h"
+
+#include "../utils/BracesAroundStatement.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/Basic/CharInfo.h"
+#include "clang/Lex/Lexer.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::modernize {
+
+namespace {
+
+struct BraceFix {
+  bool NeedsBraces = false;
+  utils::BraceInsertionHints Hints;
+};
+
+} // namespace
+
+static std::optional<SourceRange> getHeaderRange(const IfStmt *If,
+                                                 const SourceManager &SM,
+                                                 const LangOptions &LangOpts) {
+  if (If->getLParenLoc().isMacroID() || If->getRParenLoc().isMacroID())
+    return std::nullopt;
+
+  const SourceRange HeaderRange(If->getLParenLoc(), If->getRParenLoc());
+  // Validate that the token range is safely rewriteable in file source before
+  // offering a fix-it.
+  if (Lexer::makeFileCharRange(CharSourceRange::getTokenRange(HeaderRange), SM,
+                               LangOpts)
+          .isInvalid())
+    return std::nullopt;
+  return HeaderRange;
+}
+
+static std::optional<BraceFix>
+getBraceFix(const Stmt *S, const LangOptions &LangOpts, const SourceManager &SM,
+            SourceLocation StartLoc,
+            SourceLocation EndLocHint = SourceLocation()) {
+  if (S)
+    S = S->stripLabelLikeStatements();
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unterumarmung wrote:

Done

https://github.com/llvm/llvm-project/pull/189743