clang 18.0.0git
ObjCPropertyChecker.cpp
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1//==- ObjCPropertyChecker.cpp - Check ObjC properties ------------*- 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// This checker finds issues with Objective-C properties.
10// Currently finds only one kind of issue:
11// - Find synthesized properties with copy attribute of mutable NS collection
12// types. Calling -copy on such collections produces an immutable copy,
13// which contradicts the type of the property.
14//
15//===----------------------------------------------------------------------===//
16
20
21using namespace clang;
22using namespace ento;
23
24namespace {
25class ObjCPropertyChecker
26 : public Checker<check::ASTDecl<ObjCPropertyDecl>> {
27 void checkCopyMutable(const ObjCPropertyDecl *D, BugReporter &BR) const;
28
29public:
30 void checkASTDecl(const ObjCPropertyDecl *D, AnalysisManager &Mgr,
31 BugReporter &BR) const;
32};
33} // end anonymous namespace.
34
35void ObjCPropertyChecker::checkASTDecl(const ObjCPropertyDecl *D,
36 AnalysisManager &Mgr,
37 BugReporter &BR) const {
38 checkCopyMutable(D, BR);
39}
40
41void ObjCPropertyChecker::checkCopyMutable(const ObjCPropertyDecl *D,
42 BugReporter &BR) const {
44 return;
45
46 QualType T = D->getType();
48 return;
49
50 const std::string &PropTypeName(T->getPointeeType().getCanonicalType()
52 .getAsString());
53 if (!StringRef(PropTypeName).startswith("NSMutable"))
54 return;
55
56 const ObjCImplDecl *ImplD = nullptr;
57 if (const ObjCInterfaceDecl *IntD =
58 dyn_cast<ObjCInterfaceDecl>(D->getDeclContext())) {
59 ImplD = IntD->getImplementation();
60 } else if (auto *CatD = dyn_cast<ObjCCategoryDecl>(D->getDeclContext())) {
61 ImplD = CatD->getClassInterface()->getImplementation();
62 }
63
64 if (!ImplD || ImplD->HasUserDeclaredSetterMethod(D))
65 return;
66
68 llvm::raw_svector_ostream OS(Str);
69 OS << "Property of mutable type '" << PropTypeName
70 << "' has 'copy' attribute; an immutable object will be stored instead";
71
73 D, this, "Objective-C property misuse", "Logic error", OS.str(),
75 D->getSourceRange());
76}
77
78void ento::registerObjCPropertyChecker(CheckerManager &Mgr) {
79 Mgr.registerChecker<ObjCPropertyChecker>();
80}
81
82bool ento::shouldRegisterObjCPropertyChecker(const CheckerManager &mgr) {
83 return true;
84}
DeclContext * getDeclContext()
Definition: DeclBase.h:453
bool HasUserDeclaredSetterMethod(const ObjCPropertyDecl *P) const
This routine returns 'true' if a user declared setter method was found in the class,...
Definition: DeclObjC.cpp:124
const ObjCInterfaceDecl * getClassInterface() const
Definition: DeclObjC.h:2483
Represents an ObjC class declaration.
Definition: DeclObjC.h:1150
ObjCImplementationDecl * getImplementation() const
Definition: DeclObjC.cpp:1635
Represents one property declaration in an Objective-C interface.
Definition: DeclObjC.h:729
SourceRange getSourceRange() const override LLVM_READONLY
Source range that this declaration covers.
Definition: DeclObjC.h:924
bool isReadOnly() const
isReadOnly - Return true iff the property has a setter.
Definition: DeclObjC.h:834
SetterKind getSetterKind() const
getSetterKind - Return the method used for doing assignment in the property setter.
Definition: DeclObjC.h:869
QualType getType() const
Definition: DeclObjC.h:800
A (possibly-)qualified type.
Definition: Type.h:736
QualType getCanonicalType() const
Definition: Type.h:6833
QualType getUnqualifiedType() const
Retrieve the unqualified variant of the given type, removing as little sugar as possible.
Definition: Type.h:6874
static std::string getAsString(SplitQualType split, const PrintingPolicy &Policy)
Definition: Type.h:1120
QualType getPointeeType() const
If this is a pointer, ObjC object pointer, or block pointer, this returns the respective pointee.
Definition: Type.cpp:651
bool isObjCObjectPointerType() const
Definition: Type.h:7161
BugReporter is a utility class for generating PathDiagnostics for analysis.
Definition: BugReporter.h:584
const SourceManager & getSourceManager()
Definition: BugReporter.h:616
void EmitBasicReport(const Decl *DeclWithIssue, const CheckerBase *Checker, StringRef BugName, StringRef BugCategory, StringRef BugStr, PathDiagnosticLocation Loc, ArrayRef< SourceRange > Ranges=std::nullopt, ArrayRef< FixItHint > Fixits=std::nullopt)
CHECKER * registerChecker(AT &&... Args)
Used to register checkers.
static PathDiagnosticLocation createBegin(const Decl *D, const SourceManager &SM)
Create a location for the beginning of the declaration.