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 | |