[clang-tools-extra] Enforce SL.con.3: Add check to replace operator[] with at() [Cont.] (PR #95220)

[Paul Heidekrüger via cfe-commits]

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@@ -0,0 +1,124 @@
+//===--- ProBoundsAvoidUncheckedContainerAccesses.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 "ProBoundsAvoidUncheckedContainerAccesses.h"
+#include "../utils/Matchers.h"
+#include "../utils/OptionsUtils.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "llvm/ADT/StringRef.h"
+#include <numeric>
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::cppcoreguidelines {
+
+static constexpr std::array<llvm::StringRef, 3> SubscriptDefaultExclusions = {
+    llvm::StringRef("::std::map"), llvm::StringRef("::std::unordered_map"),
+    llvm::StringRef("::std::flat_map")};
+
+ProBoundsAvoidUncheckedContainerAccesses::
+    ProBoundsAvoidUncheckedContainerAccesses(StringRef Name,
+                                             ClangTidyContext *Context)
+    : ClangTidyCheck(Name, Context) {
+
+  SubscriptExcludedClasses = clang::tidy::utils::options::parseStringList(
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PBHDK wrote:

If we were just to rely on the `const` check, we would also be excluding std::vectors for instance, because their subscript operator might not be `const` either, as it returns a reference. Correct?

https://github.com/llvm/llvm-project/pull/95220