llvm-project/clang-tools-extra/clang-tidy/abseil/DurationUnnecessaryConversi...

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4.7 KiB
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//===--- DurationUnnecessaryConversionCheck.cpp - clang-tidy
//-----------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "DurationUnnecessaryConversionCheck.h"
#include "DurationRewriter.h"
#include "clang/AST/ASTContext.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"
#include "clang/Tooling/FixIt.h"
using namespace clang::ast_matchers;
namespace clang {
namespace tidy {
namespace abseil {
void DurationUnnecessaryConversionCheck::registerMatchers(MatchFinder *Finder) {
for (const auto &Scale : {"Hours", "Minutes", "Seconds", "Milliseconds",
"Microseconds", "Nanoseconds"}) {
std::string DurationFactory = (llvm::Twine("::absl::") + Scale).str();
std::string FloatConversion =
(llvm::Twine("::absl::ToDouble") + Scale).str();
std::string IntegerConversion =
(llvm::Twine("::absl::ToInt64") + Scale).str();
// Matcher which matches the current scale's factory with a `1` argument,
// e.g. `absl::Seconds(1)`.
auto FactoryMatcher = ignoringElidableConstructorCall(
callExpr(callee(functionDecl(hasName(DurationFactory))),
hasArgument(0, ignoringImpCasts(integerLiteral(equals(1))))));
// Matcher which matches either inverse function and binds its argument,
// e.g. `absl::ToDoubleSeconds(dur)`.
auto InverseFunctionMatcher = callExpr(
callee(functionDecl(hasAnyName(FloatConversion, IntegerConversion))),
hasArgument(0, expr().bind("arg")));
// Matcher which matches a duration divided by the factory_matcher above,
// e.g. `dur / absl::Seconds(1)`.
auto DivisionOperatorMatcher = cxxOperatorCallExpr(
hasOverloadedOperatorName("/"), hasArgument(0, expr().bind("arg")),
hasArgument(1, FactoryMatcher));
// Matcher which matches a duration argument to `FDivDuration`,
// e.g. `absl::FDivDuration(dur, absl::Seconds(1))`
auto FdivMatcher = callExpr(
callee(functionDecl(hasName("::absl::FDivDuration"))),
hasArgument(0, expr().bind("arg")), hasArgument(1, FactoryMatcher));
// Matcher which matches a duration argument being scaled,
// e.g. `absl::ToDoubleSeconds(dur) * 2`
auto ScalarMatcher = ignoringImpCasts(
binaryOperator(hasOperatorName("*"),
hasEitherOperand(expr(ignoringParenImpCasts(
callExpr(callee(functionDecl(hasAnyName(
FloatConversion, IntegerConversion))),
hasArgument(0, expr().bind("arg")))
.bind("inner_call")))))
.bind("binop"));
Finder->addMatcher(
callExpr(callee(functionDecl(hasName(DurationFactory))),
hasArgument(0, anyOf(InverseFunctionMatcher,
DivisionOperatorMatcher, FdivMatcher,
ScalarMatcher)))
.bind("call"),
this);
}
}
void DurationUnnecessaryConversionCheck::check(
const MatchFinder::MatchResult &Result) {
const auto *OuterCall = Result.Nodes.getNodeAs<Expr>("call");
if (isInMacro(Result, OuterCall))
return;
FixItHint Hint;
if (const auto *Binop = Result.Nodes.getNodeAs<BinaryOperator>("binop")) {
const auto *Arg = Result.Nodes.getNodeAs<Expr>("arg");
const auto *InnerCall = Result.Nodes.getNodeAs<Expr>("inner_call");
const Expr *LHS = Binop->getLHS();
const Expr *RHS = Binop->getRHS();
if (LHS->IgnoreParenImpCasts() == InnerCall) {
Hint = FixItHint::CreateReplacement(
OuterCall->getSourceRange(),
(llvm::Twine(tooling::fixit::getText(*Arg, *Result.Context)) + " * " +
tooling::fixit::getText(*RHS, *Result.Context))
.str());
} else {
assert(RHS->IgnoreParenImpCasts() == InnerCall &&
"Inner call should be find on the RHS");
Hint = FixItHint::CreateReplacement(
OuterCall->getSourceRange(),
(llvm::Twine(tooling::fixit::getText(*LHS, *Result.Context)) + " * " +
tooling::fixit::getText(*Arg, *Result.Context))
.str());
}
} else if (const auto *Arg = Result.Nodes.getNodeAs<Expr>("arg")) {
Hint = FixItHint::CreateReplacement(
OuterCall->getSourceRange(),
tooling::fixit::getText(*Arg, *Result.Context));
}
diag(OuterCall->getBeginLoc(),
"remove unnecessary absl::Duration conversions")
<< Hint;
}
} // namespace abseil
} // namespace tidy
} // namespace clang