[clang-tools-extra] [clang-tidy] Add readability-redundant-lambda-parentheses check (PR #190438)

[Julian Schmidt via cfe-commits]

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@@ -0,0 +1,88 @@
+//===----------------------------------------------------------------------===//
+//
+// 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 "RedundantLambdaParenthesesCheck.h"
+#include "clang/Lex/Lexer.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::readability {
+
+void RedundantLambdaParenthesesCheck::registerMatchers(MatchFinder *Finder) {
+  Finder->addMatcher(lambdaExpr().bind("lambda"), this);
+}
+
+void RedundantLambdaParenthesesCheck::check(
+    const MatchFinder::MatchResult &Result) {
+  const auto *Lambda = Result.Nodes.getNodeAs<LambdaExpr>("lambda");
+
+  if (Lambda->getBeginLoc().isMacroID())
+    return;
+
+  if (!Lambda->hasExplicitParameters() && !Lambda->isGenericLambda())
+    return;
+
+  if (Lambda->getCallOperator()->getNumParams() != 0)
+    return;
+
+  if (Lambda->isGenericLambda() && !getLangOpts().CPlusPlus20)
+    return;
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5chmidti wrote:

please move these into matchers

https://github.com/llvm/llvm-project/pull/190438