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

[Baranov Victor via cfe-commits]

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@@ -16,13 +17,13 @@ using namespace clang::ast_matchers;
 namespace clang::tidy::modernize {
 
 static StringRef toStringViewTypeStr(StringRef Type) {
-  if (Type.contains("wchar_t"))
+  if (Type.contains("wchar_t") || Type.ends_with("wstring"))
     return "std::wstring_view";
-  if (Type.contains("char8_t"))
+  if (Type.contains("char8_t") || Type.ends_with("u8string"))
     return "std::u8string_view";
-  if (Type.contains("char16_t"))
+  if (Type.contains("char16_t") || Type.ends_with("u16string"))
     return "std::u16string_view";
-  if (Type.contains("char32_t"))
+  if (Type.contains("char32_t") || Type.ends_with("u32string"))
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vbvictor wrote:

Can we make a separate test with mocks that mimic stdlib behavior in Chromium? Otherwise, someone could refactor this check and break it's "undocumented" behavoir.

Could you use `getReturnType().getUnqualifiedDesugaredType()`, it should produce `basic_string<...>`.

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