[clang-tools-extra] [clang-tidy] Add readability-default-lambda-capture (PR #160150)

[JJ Marr via cfe-commits]

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@@ -0,0 +1,40 @@
+//===----------------------------------------------------------------------===//
+//
+// 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 "AvoidDefaultLambdaCaptureCheck.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::readability {
+
+namespace {
+AST_MATCHER(LambdaExpr, hasDefaultCapture) {
+  return Node.getCaptureDefault() != LCD_None;
+}
+
+} // namespace
+
+void AvoidDefaultLambdaCaptureCheck::registerMatchers(MatchFinder *Finder) {
+  Finder->addMatcher(lambdaExpr(hasDefaultCapture()).bind("lambda"), this);
+}
+
+void AvoidDefaultLambdaCaptureCheck::check(
+    const MatchFinder::MatchResult &Result) {
+  const auto *Lambda = Result.Nodes.getNodeAs<LambdaExpr>("lambda");
+  assert(Lambda);
+
+  const SourceLocation DefaultCaptureLoc = Lambda->getCaptureDefaultLoc();
+  if (DefaultCaptureLoc.isInvalid())
+    return;
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jjmarr-amd wrote:

I feel like there should be a logged warning here or something even though I haven't seen this elsewhere in LLVM.

https://github.com/llvm/llvm-project/pull/160150