clang-tools  10.0.0git
DurationUnnecessaryConversionCheck.cpp
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1 //===--- DurationUnnecessaryConversionCheck.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 
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 
22 void DurationUnnecessaryConversionCheck::registerMatchers(MatchFinder *Finder) {
23  for (const auto &Scale : {"Hours", "Minutes", "Seconds", "Milliseconds",
24  "Microseconds", "Nanoseconds"}) {
25  std::string DurationFactory = (llvm::Twine("::absl::") + Scale).str();
26  std::string FloatConversion =
27  (llvm::Twine("::absl::ToDouble") + Scale).str();
28  std::string IntegerConversion =
29  (llvm::Twine("::absl::ToInt64") + Scale).str();
30 
31  // Matcher which matches the current scale's factory with a `1` argument,
32  // e.g. `absl::Seconds(1)`.
33  auto factory_matcher = ignoringElidableConstructorCall(
34  callExpr(callee(functionDecl(hasName(DurationFactory))),
35  hasArgument(0, ignoringImpCasts(integerLiteral(equals(1))))));
36 
37  // Matcher which matches either inverse function and binds its argument,
38  // e.g. `absl::ToDoubleSeconds(dur)`.
39  auto inverse_function_matcher = callExpr(
40  callee(functionDecl(hasAnyName(FloatConversion, IntegerConversion))),
41  hasArgument(0, expr().bind("arg")));
42 
43  // Matcher which matches a duration divided by the factory_matcher above,
44  // e.g. `dur / absl::Seconds(1)`.
45  auto division_operator_matcher = cxxOperatorCallExpr(
46  hasOverloadedOperatorName("/"), hasArgument(0, expr().bind("arg")),
47  hasArgument(1, factory_matcher));
48 
49  // Matcher which matches a duration argument to `FDivDuration`,
50  // e.g. `absl::FDivDuration(dur, absl::Seconds(1))`
51  auto fdiv_matcher = callExpr(
52  callee(functionDecl(hasName("::absl::FDivDuration"))),
53  hasArgument(0, expr().bind("arg")), hasArgument(1, factory_matcher));
54 
55  Finder->addMatcher(
56  callExpr(callee(functionDecl(hasName(DurationFactory))),
57  hasArgument(0, anyOf(inverse_function_matcher,
58  division_operator_matcher, fdiv_matcher)))
59  .bind("call"),
60  this);
61  }
62 }
63 
64 void DurationUnnecessaryConversionCheck::check(
65  const MatchFinder::MatchResult &Result) {
66  const auto *OuterCall = Result.Nodes.getNodeAs<Expr>("call");
67  const auto *Arg = Result.Nodes.getNodeAs<Expr>("arg");
68 
69  if (isInMacro(Result, OuterCall))
70  return;
71 
72  diag(OuterCall->getBeginLoc(),
73  "remove unnecessary absl::Duration conversions")
74  << FixItHint::CreateReplacement(
75  OuterCall->getSourceRange(),
76  tooling::fixit::getText(*Arg, *Result.Context));
77 }
78 
79 } // namespace abseil
80 } // namespace tidy
81 } // namespace clang
bool isInMacro(const MatchFinder::MatchResult &Result, const Expr *E)
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//