1 //===--- AssignmentInIfConditionCheck.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 "AssignmentInIfConditionCheck.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 bugprone {
18
registerMatchers(MatchFinder * Finder)19 void AssignmentInIfConditionCheck::registerMatchers(MatchFinder *Finder) {
20 Finder->addMatcher(ifStmt(hasCondition(forEachDescendant(
21 binaryOperator(isAssignmentOperator())
22 .bind("assignment_in_if_statement")))),
23 this);
24 Finder->addMatcher(ifStmt(hasCondition(forEachDescendant(
25 cxxOperatorCallExpr(isAssignmentOperator())
26 .bind("assignment_in_if_statement")))),
27 this);
28 }
29
check(const MatchFinder::MatchResult & Result)30 void AssignmentInIfConditionCheck::check(
31 const MatchFinder::MatchResult &Result) {
32 const auto *MatchedDecl =
33 Result.Nodes.getNodeAs<clang::Stmt>("assignment_in_if_statement");
34 if (!MatchedDecl) {
35 return;
36 }
37 diag(MatchedDecl->getBeginLoc(),
38 "an assignment within an 'if' condition is bug-prone");
39 diag(MatchedDecl->getBeginLoc(),
40 "if it should be an assignment, move it out of the 'if' condition",
41 DiagnosticIDs::Note);
42 diag(MatchedDecl->getBeginLoc(),
43 "if it is meant to be an equality check, change '=' to '=='",
44 DiagnosticIDs::Note);
45 }
46
47 } // namespace bugprone
48 } // namespace tidy
49 } // namespace clang
50