clang-tools-extra/clang-tidy/objc/MissingHashCheck.cpp

   1 //===--- MissingHashCheck.cpp - 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 #include "MissingHashCheck.h"
  10 #include "clang/AST/ASTContext.h"
  11 #include "clang/ASTMatchers/ASTMatchFinder.h"
  12
  13 using namespace clang::ast_matchers;
  14
  15 namespace clang {
  16 namespace tidy {
  17 namespace objc {
  18
  19 namespace {
  20
  21 AST_MATCHER_P(ObjCImplementationDecl, hasInterface,
  22               ast_matchers::internal::Matcher<ObjCInterfaceDecl>, Base) {
  23   const ObjCInterfaceDecl *InterfaceDecl = Node.getClassInterface();
  24   return Base.matches(*InterfaceDecl, Finder, Builder);
  25 }
  26
  27 AST_MATCHER_P(ObjCContainerDecl, hasInstanceMethod,
  28               ast_matchers::internal::Matcher<ObjCMethodDecl>, Base) {
  29   // Check each instance method against the provided matcher.
  30   for (const auto *I : Node.instance_methods()) {
  31     if (Base.matches(*I, Finder, Builder))
  32       return true;
  33   }
  34   return false;
  35 }
  36
  37 } // namespace
  38
  39 void MissingHashCheck::registerMatchers(MatchFinder *Finder) {
  40   Finder->addMatcher(
  41       objcMethodDecl(
  42           hasName("isEqual:"), isInstanceMethod(),
  43           hasDeclContext(objcImplementationDecl(
  44                              hasInterface(isDirectlyDerivedFrom("NSObject")),
  45                              unless(hasInstanceMethod(hasName("hash"))))
  46                              .bind("impl"))),
  47       this);
  48 }
  49
  50 void MissingHashCheck::check(const MatchFinder::MatchResult &Result) {
  51   const auto *ID = Result.Nodes.getNodeAs<ObjCImplementationDecl>("impl");
  52   diag(ID->getLocation(), "%0 implements -isEqual: without implementing -hash")
  53       << ID;
  54 }
  55
  56 } // namespace objc
  57 } // namespace tidy
  58 } // namespace clang