build/clang-plugin/ExplicitOperatorBoolChecker.cpp

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this
   3  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   4
   5 #include "ExplicitOperatorBoolChecker.h"
   6 #include "CustomMatchers.h"
   7
   8 void ExplicitOperatorBoolChecker::registerMatchers(MatchFinder *AstMatcher) {
   9   // Older clang versions such as the ones used on the infra recognize these
  10   // conversions as 'operator _Bool', but newer clang versions recognize these
  11   // as 'operator bool'.
  12   AstMatcher->addMatcher(
  13       cxxMethodDecl(anyOf(hasName("operator bool"), hasName("operator _Bool")))
  14           .bind("node"),
  15       this);
  16 }
  17
  18 void ExplicitOperatorBoolChecker::check(
  19     const MatchFinder::MatchResult &Result) {
  20   const CXXConversionDecl *Method =
  21       Result.Nodes.getNodeAs<CXXConversionDecl>("node");
  22   const CXXRecordDecl *Clazz = Method->getParent();
  23
  24   if (!Method->isExplicitSpecified() &&
  25       !hasCustomAttribute<moz_implicit>(Method) &&
  26       !ASTIsInSystemHeader(Method->getASTContext(), *Method) &&
  27       isInterestingDeclForImplicitConversion(Method)) {
  28     diag(Method->getBeginLoc(), "bad implicit conversion operator for %0",
  29          DiagnosticIDs::Error)
  30         << Clazz;
  31     diag(Method->getBeginLoc(), "consider adding the explicit keyword to %0",
  32          DiagnosticIDs::Note)
  33         << "'operator bool'";
  34   }
  35 }