1 //===--- TimeComparisonCheck.cpp - clang-tidy
2 //--------------------------------===//
3 //
4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5 // See https://llvm.org/LICENSE.txt for license information.
6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "TimeComparisonCheck.h"
11 #include "DurationRewriter.h"
12 #include "clang/AST/ASTContext.h"
13 #include "clang/ASTMatchers/ASTMatchFinder.h"
14 #include "clang/Tooling/FixIt.h"
15 
16 using namespace clang::ast_matchers;
17 
18 namespace clang {
19 namespace tidy {
20 namespace abseil {
21 
registerMatchers(MatchFinder * Finder)22 void TimeComparisonCheck::registerMatchers(MatchFinder *Finder) {
23   auto Matcher =
24       expr(comparisonOperatorWithCallee(functionDecl(
25                functionDecl(TimeConversionFunction()).bind("function_decl"))))
26           .bind("binop");
27 
28   Finder->addMatcher(Matcher, this);
29 }
30 
check(const MatchFinder::MatchResult & Result)31 void TimeComparisonCheck::check(const MatchFinder::MatchResult &Result) {
32   const auto *Binop = Result.Nodes.getNodeAs<BinaryOperator>("binop");
33 
34   llvm::Optional<DurationScale> Scale = getScaleForTimeInverse(
35       Result.Nodes.getNodeAs<FunctionDecl>("function_decl")->getName());
36   if (!Scale)
37     return;
38 
39   if (isInMacro(Result, Binop->getLHS()) || isInMacro(Result, Binop->getRHS()))
40     return;
41 
42   // In most cases, we'll only need to rewrite one of the sides, but we also
43   // want to handle the case of rewriting both sides. This is much simpler if
44   // we unconditionally try and rewrite both, and let the rewriter determine
45   // if nothing needs to be done.
46   std::string LhsReplacement =
47       rewriteExprFromNumberToTime(Result, *Scale, Binop->getLHS());
48   std::string RhsReplacement =
49       rewriteExprFromNumberToTime(Result, *Scale, Binop->getRHS());
50 
51   diag(Binop->getBeginLoc(), "perform comparison in the time domain")
52       << FixItHint::CreateReplacement(Binop->getSourceRange(),
53                                       (llvm::Twine(LhsReplacement) + " " +
54                                        Binop->getOpcodeStr() + " " +
55                                        RhsReplacement)
56                                           .str());
57 }
58 
59 } // namespace abseil
60 } // namespace tidy
61 } // namespace clang
62