diff options
| -rw-r--r-- | clang-tools-extra/clang-tidy/utils/ExprMutationAnalyzer.cpp | 42 | ||||
| -rw-r--r-- | clang-tools-extra/unittests/clang-tidy/ExprMutationAnalyzerTest.cpp | 59 |
2 files changed, 99 insertions, 2 deletions
diff --git a/clang-tools-extra/clang-tidy/utils/ExprMutationAnalyzer.cpp b/clang-tools-extra/clang-tidy/utils/ExprMutationAnalyzer.cpp index f979e97a03d..1ec1f7270f3 100644 --- a/clang-tools-extra/clang-tidy/utils/ExprMutationAnalyzer.cpp +++ b/clang-tools-extra/clang-tidy/utils/ExprMutationAnalyzer.cpp @@ -51,6 +51,20 @@ const auto nonConstReferenceType = [] { return referenceType(pointee(unless(isConstQualified()))); }; +const auto nonConstPointerType = [] { + return pointerType(pointee(unless(isConstQualified()))); +}; + +const auto isMoveOnly = [] { + return cxxRecordDecl( + hasMethod(cxxConstructorDecl(isMoveConstructor(), unless(isDeleted()))), + hasMethod(cxxMethodDecl(isMoveAssignmentOperator(), unless(isDeleted()))), + unless(anyOf(hasMethod(cxxConstructorDecl(isCopyConstructor(), + unless(isDeleted()))), + hasMethod(cxxMethodDecl(isCopyAssignmentOperator(), + unless(isDeleted())))))); +}; + } // namespace const Stmt *ExprMutationAnalyzer::findMutation(const Expr *Exp) { @@ -168,6 +182,15 @@ const Stmt *ExprMutationAnalyzer::findDirectMutation(const Expr *Exp) { const auto AsPointerFromArrayDecay = castExpr(hasCastKind(CK_ArrayToPointerDecay), unless(hasParent(arraySubscriptExpr())), has(equalsNode(Exp))); + // Treat calling `operator->()` of move-only classes as taking address. + // These are typically smart pointers with unique ownership so we treat + // mutation of pointee as mutation of the smart pointer itself. + const auto AsOperatorArrowThis = cxxOperatorCallExpr( + hasOverloadedOperatorName("->"), + callee(cxxMethodDecl( + ofClass(isMoveOnly()), + returns(hasUnqualifiedDesugaredType(nonConstPointerType())))), + argumentCountIs(1), hasArgument(0, equalsNode(Exp))); // Used as non-const-ref argument when calling a function. // An argument is assumed to be non-const-ref when the function is unresolved. @@ -197,8 +220,8 @@ const Stmt *ExprMutationAnalyzer::findDirectMutation(const Expr *Exp) { const auto Matches = match(findAll(stmt(anyOf(AsAssignmentLhs, AsIncDecOperand, AsNonConstThis, AsAmpersandOperand, AsPointerFromArrayDecay, - AsNonConstRefArg, AsLambdaRefCaptureInit, - AsNonConstRefReturn)) + AsOperatorArrowThis, AsNonConstRefArg, + AsLambdaRefCaptureInit, AsNonConstRefReturn)) .bind("stmt")), Stm, Context); return selectFirst<Stmt>("stmt", Matches); @@ -250,6 +273,21 @@ const Stmt *ExprMutationAnalyzer::findRangeLoopMutation(const Expr *Exp) { } const Stmt *ExprMutationAnalyzer::findReferenceMutation(const Expr *Exp) { + // Follow non-const reference returned by `operator*()` of move-only classes. + // These are typically smart pointers with unique ownership so we treat + // mutation of pointee as mutation of the smart pointer itself. + const auto Ref = match( + findAll(cxxOperatorCallExpr( + hasOverloadedOperatorName("*"), + callee(cxxMethodDecl(ofClass(isMoveOnly()), + returns(hasUnqualifiedDesugaredType( + nonConstReferenceType())))), + argumentCountIs(1), hasArgument(0, equalsNode(Exp))) + .bind("expr")), + Stm, Context); + if (const Stmt *S = findExprMutation(Ref)) + return S; + // If 'Exp' is bound to a non-const reference, check all declRefExpr to that. const auto Refs = match( stmt(forEachDescendant( diff --git a/clang-tools-extra/unittests/clang-tidy/ExprMutationAnalyzerTest.cpp b/clang-tools-extra/unittests/clang-tidy/ExprMutationAnalyzerTest.cpp index 71511d635a9..14878ed119f 100644 --- a/clang-tools-extra/unittests/clang-tidy/ExprMutationAnalyzerTest.cpp +++ b/clang-tools-extra/unittests/clang-tidy/ExprMutationAnalyzerTest.cpp @@ -724,6 +724,65 @@ TEST(ExprMutationAnalyzerTest, NotUnevaluatedExpressions) { EXPECT_THAT(mutatedBy(Results, AST.get()), ElementsAre("x.f()")); } +TEST(ExprMutationAnalyzerTest, UniquePtr) { + const std::string UniquePtrDef = + "template <class T> struct UniquePtr {" + " UniquePtr();" + " UniquePtr(const UniquePtr&) = delete;" + " UniquePtr(UniquePtr&&);" + " UniquePtr& operator=(const UniquePtr&) = delete;" + " UniquePtr& operator=(UniquePtr&&);" + " T& operator*() const;" + " T* operator->() const;" + "};"; + + auto AST = tooling::buildASTFromCode( + UniquePtrDef + "void f() { UniquePtr<int> x; *x = 10; }"); + auto Results = + match(withEnclosingCompound(declRefTo("x")), AST->getASTContext()); + EXPECT_THAT(mutatedBy(Results, AST.get()), ElementsAre("* x = 10")); + + AST = tooling::buildASTFromCode(UniquePtrDef + + "void f() { UniquePtr<int> x; *x; }"); + Results = match(withEnclosingCompound(declRefTo("x")), AST->getASTContext()); + EXPECT_FALSE(isMutated(Results, AST.get())); + + AST = tooling::buildASTFromCode(UniquePtrDef + + "void f() { UniquePtr<const int> x; *x; }"); + Results = match(withEnclosingCompound(declRefTo("x")), AST->getASTContext()); + EXPECT_FALSE(isMutated(Results, AST.get())); + + AST = tooling::buildASTFromCode(UniquePtrDef + + "struct S { int v; };" + "void f() { UniquePtr<S> x; x->v; }"); + Results = match(withEnclosingCompound(declRefTo("x")), AST->getASTContext()); + EXPECT_THAT(mutatedBy(Results, AST.get()), ElementsAre("x")); + + AST = tooling::buildASTFromCode(UniquePtrDef + + "struct S { int v; };" + "void f() { UniquePtr<const S> x; x->v; }"); + Results = match(withEnclosingCompound(declRefTo("x")), AST->getASTContext()); + EXPECT_FALSE(isMutated(Results, AST.get())); + + AST = tooling::buildASTFromCode(UniquePtrDef + + "struct S { void mf(); };" + "void f() { UniquePtr<S> x; x->mf(); }"); + Results = match(withEnclosingCompound(declRefTo("x")), AST->getASTContext()); + EXPECT_THAT(mutatedBy(Results, AST.get()), ElementsAre("x")); + + AST = tooling::buildASTFromCode( + UniquePtrDef + "struct S { void mf() const; };" + "void f() { UniquePtr<const S> x; x->mf(); }"); + Results = match(withEnclosingCompound(declRefTo("x")), AST->getASTContext()); + EXPECT_FALSE(isMutated(Results, AST.get())); + + AST = tooling::buildASTFromCodeWithArgs( + UniquePtrDef + "template <class T> void f() { UniquePtr<T> x; x->mf(); }", + {"-fno-delayed-template-parsing"}); + Results = match(withEnclosingCompound(declRefTo("x")), AST->getASTContext()); + EXPECT_THAT(mutatedBy(Results, AST.get()), ElementsAre("x->mf()")); +} + } // namespace test } // namespace tidy } // namespace clang |
