| 1 | //===--- StringviewNullptrCheck.h - clang-tidy ------------------*- C++ -*-===// |
| 2 | // |
| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| 4 | // See https://llvm.org/LICENSE.txt for license information. |
| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| 6 | // |
| 7 | //===----------------------------------------------------------------------===// |
| 8 | |
| 9 | #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_STRINGVIEWNULLPTRCHECK_H |
| 10 | #define |
| 11 | |
| 12 | #include "../utils/TransformerClangTidyCheck.h" |
| 13 | |
| 14 | namespace clang::tidy::bugprone { |
| 15 | |
| 16 | /// Checks for various ways that the `const CharT*` constructor of |
| 17 | /// `std::basic_string_view` can be passed a null argument and replaces them |
| 18 | /// with the default constructor in most cases. For the comparison operators, |
| 19 | /// braced initializer list does not compile so instead a call to `.empty()` or |
| 20 | /// the empty string literal are used, where appropriate. |
| 21 | /// |
| 22 | /// This prevents code from invoking behavior which is unconditionally |
| 23 | /// undefined. The single-argument `const CharT*` constructor does not check |
| 24 | /// for the null case before dereferencing its input. The standard is slated to |
| 25 | /// add an explicitly-deleted overload to catch some of these cases: |
| 26 | /// wg21.link/p2166 |
| 27 | /// |
| 28 | /// To catch the additional cases of `NULL` (which expands to `__null`) and |
| 29 | /// `0`, first run the ``modernize-use-nullptr`` check to convert the callers |
| 30 | /// to `nullptr`. |
| 31 | /// |
| 32 | /// For the user-facing documentation see: |
| 33 | /// http://clang.llvm.org/extra/clang-tidy/checks/bugprone/stringview-nullptr.html |
| 34 | class StringviewNullptrCheck : public utils::TransformerClangTidyCheck { |
| 35 | public: |
| 36 | StringviewNullptrCheck(StringRef Name, ClangTidyContext *Context); |
| 37 | |
| 38 | bool isLanguageVersionSupported(const LangOptions &LangOpts) const override { |
| 39 | return LangOpts.CPlusPlus17; |
| 40 | } |
| 41 | }; |
| 42 | |
| 43 | } // namespace clang::tidy::bugprone |
| 44 | |
| 45 | #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_STRINGVIEWNULLPTRCHECK_H |
| 46 | |