[clang-tools-extra] [clang-tidy] Add a new check 'replace-with-string-view' (PR #172170)

[Zinovy Nis via cfe-commits]

================
@@ -0,0 +1,67 @@
+//===----------------------------------------------------------------------===//
+//
+// 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 "ReplaceWithStringViewCheck.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::performance {
+
+static llvm::StringLiteral toStringViewTypeStr(StringRef Type) {
+  if (Type.contains("wchar_t"))
----------------
irishrover wrote:

`Type` is long and boring string like

```
std::wstring_view (C++17) | std::basic_string_view<wchar_t>
std::u8string_view (C++20) | std::basic_string_view<char8_t>
std::u16string_view (C++17) | std::basic_string_view<char16_t>
std::u32string_view (C++17) | std::basic_string_view<char32_t>
```

https://github.com/llvm/llvm-project/pull/172170