clang-tools  10.0.0git
MutatingCopyCheck.cpp
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1 //===--- MutatingCopyCheck.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 "MutatingCopyCheck.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 cert {
18 
19 static constexpr llvm::StringLiteral SourceDeclName = "ChangedPVD";
20 static constexpr llvm::StringLiteral MutatingOperatorName = "MutatingOp";
21 static constexpr llvm::StringLiteral MutatingCallName = "MutatingCall";
22 
23 void MutatingCopyCheck::registerMatchers(MatchFinder *Finder) {
24  if (!getLangOpts().CPlusPlus)
25  return;
26 
27  const auto MemberExprOrSourceObject = anyOf(
28  memberExpr(), declRefExpr(to(decl(equalsBoundNode(SourceDeclName)))));
29 
30  const auto IsPartOfSource =
31  allOf(unless(hasDescendant(expr(unless(MemberExprOrSourceObject)))),
32  MemberExprOrSourceObject);
33 
34  const auto IsSourceMutatingAssignment =
35  expr(anyOf(binaryOperator(isAssignmentOperator(), hasLHS(IsPartOfSource))
36  .bind(MutatingOperatorName),
37  cxxOperatorCallExpr(isAssignmentOperator(),
38  hasArgument(0, IsPartOfSource))
39  .bind(MutatingOperatorName)));
40 
41  const auto MemberExprOrSelf = anyOf(memberExpr(), cxxThisExpr());
42 
43  const auto IsPartOfSelf = allOf(
44  unless(hasDescendant(expr(unless(MemberExprOrSelf)))), MemberExprOrSelf);
45 
46  const auto IsSelfMutatingAssignment =
47  expr(anyOf(binaryOperator(isAssignmentOperator(), hasLHS(IsPartOfSelf)),
48  cxxOperatorCallExpr(isAssignmentOperator(),
49  hasArgument(0, IsPartOfSelf))));
50 
51  const auto IsSelfMutatingMemberFunction =
52  functionDecl(hasBody(hasDescendant(IsSelfMutatingAssignment)));
53 
54  const auto IsSourceMutatingMemberCall =
55  cxxMemberCallExpr(on(IsPartOfSource),
56  callee(IsSelfMutatingMemberFunction))
57  .bind(MutatingCallName);
58 
59  const auto MutatesSource = allOf(
60  hasParameter(
61  0, parmVarDecl(hasType(lValueReferenceType())).bind(SourceDeclName)),
62  anyOf(forEachDescendant(IsSourceMutatingAssignment),
63  forEachDescendant(IsSourceMutatingMemberCall)));
64 
65  Finder->addMatcher(cxxConstructorDecl(isCopyConstructor(), MutatesSource),
66  this);
67 
68  Finder->addMatcher(cxxMethodDecl(isCopyAssignmentOperator(), MutatesSource),
69  this);
70 }
71 
72 void MutatingCopyCheck::check(const MatchFinder::MatchResult &Result) {
73  if (const auto *MemberCall =
74  Result.Nodes.getNodeAs<CXXMemberCallExpr>(MutatingCallName))
75  diag(MemberCall->getBeginLoc(), "call mutates copied object");
76  else if (const auto *Assignment =
77  Result.Nodes.getNodeAs<Expr>(MutatingOperatorName))
78  diag(Assignment->getBeginLoc(), "mutating copied object");
79 }
80 
81 } // namespace cert
82 } // namespace tidy
83 } // namespace clang
static constexpr llvm::StringLiteral MutatingCallName
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
static constexpr llvm::StringLiteral SourceDeclName
static constexpr llvm::StringLiteral MutatingOperatorName