clang-tools-extra/clang-tidy/utils/TransformerClangTidyCheck.h

   1 //===---------- TransformerClangTidyCheck.h - clang-tidy ------------------===//
   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_TRANSFORMER_CLANG_TIDY_CHECK_H
  10 #define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_TRANSFORMER_CLANG_TIDY_CHECK_H
  11
  12 #include "../ClangTidyCheck.h"
  13 #include "IncludeInserter.h"
  14 #include "IncludeSorter.h"
  15 #include "clang/ASTMatchers/ASTMatchFinder.h"
  16 #include "clang/Tooling/Transformer/Transformer.h"
  17 #include <optional>
  18
  19 namespace clang::tidy::utils {
  20
  21 /// A base class for defining a ClangTidy check based on a `RewriteRule`.
  22 //
  23 // For example, given a rule `MyCheckAsRewriteRule`, one can define a tidy check
  24 // as follows:
  25 //
  26 // class MyCheck : public TransformerClangTidyCheck {
  27 //  public:
  28 //   MyCheck(StringRef Name, ClangTidyContext *Context)
  29 //       : TransformerClangTidyCheck(MyCheckAsRewriteRule, Name, Context) {}
  30 // };
  31 //
  32 // `TransformerClangTidyCheck` recognizes this clang-tidy option:
  33 //
  34 //  * IncludeStyle. A string specifying which file naming convention is used by
  35 //      the source code, 'llvm' or 'google'.  Default is 'llvm'. The naming
  36 //      convention influences how canonical headers are distinguished from other
  37 //      includes.
  38 class TransformerClangTidyCheck : public ClangTidyCheck {
  39 public:
  40   TransformerClangTidyCheck(StringRef Name, ClangTidyContext *Context);
  41
  42   /// DEPRECATED: prefer the two argument constructor in conjunction with
  43   /// \c setRule.
  44   ///
  45   /// \p MakeRule generates the rewrite rule to be used by the check, based on
  46   /// the given language and clang-tidy options. It can return \c std::nullopt
  47   /// to handle cases where the options disable the check.
  48   ///
  49   /// See \c setRule for constraints on the rule.
  50   TransformerClangTidyCheck(
  51       std::function<std::optional<transformer::RewriteRuleWith<std::string>>(
  52           const LangOptions &, const OptionsView &)>
  53           MakeRule,
  54       StringRef Name, ClangTidyContext *Context);
  55
  56   /// Convenience overload of the constructor when the rule doesn't have any
  57   /// dependencies.
  58   TransformerClangTidyCheck(transformer::RewriteRuleWith<std::string> R,
  59                             StringRef Name, ClangTidyContext *Context);
  60
  61   void registerPPCallbacks(const SourceManager &SM, Preprocessor *PP,
  62                            Preprocessor *ModuleExpanderPP) override;
  63   void registerMatchers(ast_matchers::MatchFinder *Finder) final;
  64   void check(const ast_matchers::MatchFinder::MatchResult &Result) final;
  65
  66   /// Derived classes that override this function should call this method from
  67   /// the overridden method.
  68   void storeOptions(ClangTidyOptions::OptionMap &Opts) override;
  69
  70   /// Set the rule that this check implements.  All cases in the rule must have
  71   /// a non-null \c Explanation, even though \c Explanation is optional for
  72   /// RewriteRule in general. Because the primary purpose of clang-tidy checks
  73   /// is to provide users with diagnostics, we assume that a missing explanation
  74   /// is a bug.  If no explanation is desired, indicate that explicitly (for
  75   /// example, by passing `text("no explanation")` to `makeRule` as the
  76   /// `Explanation` argument).
  77   void setRule(transformer::RewriteRuleWith<std::string> R);
  78
  79 private:
  80   transformer::RewriteRuleWith<std::string> Rule;
  81   IncludeInserter Inserter;
  82 };
  83
  84 } // namespace clang::tidy::utils
  85
  86 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_TRANSFORMER_CLANG_TIDY_CHECK_H