[clang-tools-extra] Enforce SL.con.3: Add check to replace operator[] with at() (PR #90043)

[Piotr Zegar via cfe-commits]

================
@@ -0,0 +1,81 @@
+//===--- AvoidBoundsErrorsCheck.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 "AvoidBoundsErrorsCheck.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/Lex/Lexer.h"
+
+#include <iostream>
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::cppcoreguidelines {
+
+bool isApplicable(const QualType &Type) {
+  const auto TypeStr = Type.getAsString();
+  bool Result = false;
+  // Only check for containers in the std namespace
+  if (TypeStr.find("std::vector") != std::string::npos) {
+    Result = true;
+  }
+  if (TypeStr.find("std::array") != std::string::npos) {
+    Result = true;
+  }
+  if (TypeStr.find("std::deque") != std::string::npos) {
+    Result = true;
+  }
+  if (TypeStr.find("std::map") != std::string::npos) {
+    Result = true;
----------------
PiotrZSL wrote:

check may break std::map currently.
for example:
```
   someMap[key] = 10; -> someMap.at(key) = 10;
```

This would change behavior of code.

https://github.com/llvm/llvm-project/pull/90043