| //===--- SimplifyBooleanExpr.cpp clang-tidy ---------------------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "SimplifyBooleanExprCheck.h" |
| #include "clang/AST/RecursiveASTVisitor.h" |
| #include "clang/Lex/Lexer.h" |
| |
| #include <cassert> |
| #include <string> |
| #include <utility> |
| |
| using namespace clang::ast_matchers; |
| |
| namespace clang { |
| namespace tidy { |
| namespace readability { |
| |
| namespace { |
| |
| StringRef getText(const MatchFinder::MatchResult &Result, SourceRange Range) { |
| return Lexer::getSourceText(CharSourceRange::getTokenRange(Range), |
| *Result.SourceManager, |
| Result.Context->getLangOpts()); |
| } |
| |
| template <typename T> |
| StringRef getText(const MatchFinder::MatchResult &Result, T &Node) { |
| return getText(Result, Node.getSourceRange()); |
| } |
| |
| const char ConditionThenStmtId[] = "if-bool-yields-then"; |
| const char ConditionElseStmtId[] = "if-bool-yields-else"; |
| const char TernaryId[] = "ternary-bool-yields-condition"; |
| const char TernaryNegatedId[] = "ternary-bool-yields-not-condition"; |
| const char IfReturnsBoolId[] = "if-return"; |
| const char IfReturnsNotBoolId[] = "if-not-return"; |
| const char ThenLiteralId[] = "then-literal"; |
| const char IfAssignVariableId[] = "if-assign-lvalue"; |
| const char IfAssignLocId[] = "if-assign-loc"; |
| const char IfAssignBoolId[] = "if-assign"; |
| const char IfAssignNotBoolId[] = "if-assign-not"; |
| const char IfAssignObjId[] = "if-assign-obj"; |
| const char CompoundReturnId[] = "compound-return"; |
| const char CompoundBoolId[] = "compound-bool"; |
| const char CompoundNotBoolId[] = "compound-bool-not"; |
| |
| const char IfStmtId[] = "if"; |
| |
| const char SimplifyOperatorDiagnostic[] = |
| "redundant boolean literal supplied to boolean operator"; |
| const char SimplifyConditionDiagnostic[] = |
| "redundant boolean literal in if statement condition"; |
| const char SimplifyConditionalReturnDiagnostic[] = |
| "redundant boolean literal in conditional return statement"; |
| |
| const CXXBoolLiteralExpr *getBoolLiteral(const MatchFinder::MatchResult &Result, |
| StringRef Id) { |
| const auto *Literal = Result.Nodes.getNodeAs<CXXBoolLiteralExpr>(Id); |
| return (Literal && Literal->getLocStart().isMacroID()) ? nullptr : Literal; |
| } |
| |
| internal::Matcher<Stmt> returnsBool(bool Value, StringRef Id = "ignored") { |
| auto SimpleReturnsBool = |
| returnStmt(has(cxxBoolLiteral(equals(Value)).bind(Id))) |
| .bind("returns-bool"); |
| return anyOf(SimpleReturnsBool, |
| compoundStmt(statementCountIs(1), has(SimpleReturnsBool))); |
| } |
| |
| bool needsParensAfterUnaryNegation(const Expr *E) { |
| E = E->IgnoreImpCasts(); |
| if (isa<BinaryOperator>(E) || isa<ConditionalOperator>(E)) |
| return true; |
| |
| if (const auto *Op = dyn_cast<CXXOperatorCallExpr>(E)) |
| return Op->getNumArgs() == 2 && Op->getOperator() != OO_Call && |
| Op->getOperator() != OO_Subscript; |
| |
| return false; |
| } |
| |
| std::pair<BinaryOperatorKind, BinaryOperatorKind> Opposites[] = { |
| {BO_LT, BO_GE}, {BO_GT, BO_LE}, {BO_EQ, BO_NE}}; |
| |
| StringRef negatedOperator(const BinaryOperator *BinOp) { |
| const BinaryOperatorKind Opcode = BinOp->getOpcode(); |
| for (auto NegatableOp : Opposites) { |
| if (Opcode == NegatableOp.first) |
| return BinOp->getOpcodeStr(NegatableOp.second); |
| if (Opcode == NegatableOp.second) |
| return BinOp->getOpcodeStr(NegatableOp.first); |
| } |
| return StringRef(); |
| } |
| |
| std::pair<OverloadedOperatorKind, StringRef> OperatorNames[] = { |
| {OO_EqualEqual, "=="}, {OO_ExclaimEqual, "!="}, {OO_Less, "<"}, |
| {OO_GreaterEqual, ">="}, {OO_Greater, ">"}, {OO_LessEqual, "<="}}; |
| |
| StringRef getOperatorName(OverloadedOperatorKind OpKind) { |
| for (auto Name : OperatorNames) { |
| if (Name.first == OpKind) |
| return Name.second; |
| } |
| |
| return StringRef(); |
| } |
| |
| std::pair<OverloadedOperatorKind, OverloadedOperatorKind> OppositeOverloads[] = |
| {{OO_EqualEqual, OO_ExclaimEqual}, |
| {OO_Less, OO_GreaterEqual}, |
| {OO_Greater, OO_LessEqual}}; |
| |
| StringRef negatedOperator(const CXXOperatorCallExpr *OpCall) { |
| const OverloadedOperatorKind Opcode = OpCall->getOperator(); |
| for (auto NegatableOp : OppositeOverloads) { |
| if (Opcode == NegatableOp.first) |
| return getOperatorName(NegatableOp.second); |
| if (Opcode == NegatableOp.second) |
| return getOperatorName(NegatableOp.first); |
| } |
| return StringRef(); |
| } |
| |
| std::string asBool(StringRef text, bool NeedsStaticCast) { |
| if (NeedsStaticCast) |
| return ("static_cast<bool>(" + text + ")").str(); |
| |
| return text; |
| } |
| |
| bool needsNullPtrComparison(const Expr *E) { |
| if (const auto *ImpCast = dyn_cast<ImplicitCastExpr>(E)) |
| return ImpCast->getCastKind() == CK_PointerToBoolean || |
| ImpCast->getCastKind() == CK_MemberPointerToBoolean; |
| |
| return false; |
| } |
| |
| bool needsZeroComparison(const Expr *E) { |
| if (const auto *ImpCast = dyn_cast<ImplicitCastExpr>(E)) |
| return ImpCast->getCastKind() == CK_IntegralToBoolean; |
| |
| return false; |
| } |
| |
| bool needsStaticCast(const Expr *E) { |
| if (const auto *ImpCast = dyn_cast<ImplicitCastExpr>(E)) { |
| if (ImpCast->getCastKind() == CK_UserDefinedConversion && |
| ImpCast->getSubExpr()->getType()->isBooleanType()) { |
| if (const auto *MemCall = |
| dyn_cast<CXXMemberCallExpr>(ImpCast->getSubExpr())) { |
| if (const auto *MemDecl = |
| dyn_cast<CXXConversionDecl>(MemCall->getMethodDecl())) { |
| if (MemDecl->isExplicit()) |
| return true; |
| } |
| } |
| } |
| } |
| |
| E = E->IgnoreImpCasts(); |
| return !E->getType()->isBooleanType(); |
| } |
| |
| std::string compareExpressionToConstant(const MatchFinder::MatchResult &Result, |
| const Expr *E, bool Negated, |
| const char *Constant) { |
| E = E->IgnoreImpCasts(); |
| const std::string ExprText = |
| (isa<BinaryOperator>(E) ? ("(" + getText(Result, *E) + ")") |
| : getText(Result, *E)) |
| .str(); |
| return ExprText + " " + (Negated ? "!=" : "==") + " " + Constant; |
| } |
| |
| std::string compareExpressionToNullPtr(const MatchFinder::MatchResult &Result, |
| const Expr *E, bool Negated) { |
| const char *NullPtr = |
| Result.Context->getLangOpts().CPlusPlus11 ? "nullptr" : "NULL"; |
| return compareExpressionToConstant(Result, E, Negated, NullPtr); |
| } |
| |
| std::string compareExpressionToZero(const MatchFinder::MatchResult &Result, |
| const Expr *E, bool Negated) { |
| return compareExpressionToConstant(Result, E, Negated, "0"); |
| } |
| |
| std::string replacementExpression(const MatchFinder::MatchResult &Result, |
| bool Negated, const Expr *E) { |
| E = E->ignoreParenBaseCasts(); |
| const bool NeedsStaticCast = needsStaticCast(E); |
| if (Negated) { |
| if (const auto *UnOp = dyn_cast<UnaryOperator>(E)) { |
| if (UnOp->getOpcode() == UO_LNot) { |
| if (needsNullPtrComparison(UnOp->getSubExpr())) |
| return compareExpressionToNullPtr(Result, UnOp->getSubExpr(), true); |
| |
| if (needsZeroComparison(UnOp->getSubExpr())) |
| return compareExpressionToZero(Result, UnOp->getSubExpr(), true); |
| |
| return replacementExpression(Result, false, UnOp->getSubExpr()); |
| } |
| } |
| |
| if (needsNullPtrComparison(E)) |
| return compareExpressionToNullPtr(Result, E, false); |
| |
| if (needsZeroComparison(E)) |
| return compareExpressionToZero(Result, E, false); |
| |
| StringRef NegatedOperator; |
| const Expr *LHS = nullptr; |
| const Expr *RHS = nullptr; |
| if (const auto *BinOp = dyn_cast<BinaryOperator>(E)) { |
| NegatedOperator = negatedOperator(BinOp); |
| LHS = BinOp->getLHS(); |
| RHS = BinOp->getRHS(); |
| } else if (const auto *OpExpr = dyn_cast<CXXOperatorCallExpr>(E)) { |
| if (OpExpr->getNumArgs() == 2) { |
| NegatedOperator = negatedOperator(OpExpr); |
| LHS = OpExpr->getArg(0); |
| RHS = OpExpr->getArg(1); |
| } |
| } |
| if (!NegatedOperator.empty() && LHS && RHS) |
| return (asBool((getText(Result, *LHS) + " " + NegatedOperator + " " + |
| getText(Result, *RHS)) |
| .str(), |
| NeedsStaticCast)); |
| |
| StringRef Text = getText(Result, *E); |
| if (!NeedsStaticCast && needsParensAfterUnaryNegation(E)) |
| return ("!(" + Text + ")").str(); |
| |
| if (needsNullPtrComparison(E)) |
| return compareExpressionToNullPtr(Result, E, false); |
| |
| if (needsZeroComparison(E)) |
| return compareExpressionToZero(Result, E, false); |
| |
| return ("!" + asBool(Text, NeedsStaticCast)); |
| } |
| |
| if (const auto *UnOp = dyn_cast<UnaryOperator>(E)) { |
| if (UnOp->getOpcode() == UO_LNot) { |
| if (needsNullPtrComparison(UnOp->getSubExpr())) |
| return compareExpressionToNullPtr(Result, UnOp->getSubExpr(), false); |
| |
| if (needsZeroComparison(UnOp->getSubExpr())) |
| return compareExpressionToZero(Result, UnOp->getSubExpr(), false); |
| } |
| } |
| |
| if (needsNullPtrComparison(E)) |
| return compareExpressionToNullPtr(Result, E, true); |
| |
| if (needsZeroComparison(E)) |
| return compareExpressionToZero(Result, E, true); |
| |
| return asBool(getText(Result, *E), NeedsStaticCast); |
| } |
| |
| const CXXBoolLiteralExpr *stmtReturnsBool(const ReturnStmt *Ret, bool Negated) { |
| if (const auto *Bool = dyn_cast<CXXBoolLiteralExpr>(Ret->getRetValue())) { |
| if (Bool->getValue() == !Negated) |
| return Bool; |
| } |
| |
| return nullptr; |
| } |
| |
| const CXXBoolLiteralExpr *stmtReturnsBool(const IfStmt *IfRet, bool Negated) { |
| if (IfRet->getElse() != nullptr) |
| return nullptr; |
| |
| if (const auto *Ret = dyn_cast<ReturnStmt>(IfRet->getThen())) |
| return stmtReturnsBool(Ret, Negated); |
| |
| if (const auto *Compound = dyn_cast<CompoundStmt>(IfRet->getThen())) { |
| if (Compound->size() == 1) { |
| if (const auto *CompoundRet = dyn_cast<ReturnStmt>(Compound->body_back())) |
| return stmtReturnsBool(CompoundRet, Negated); |
| } |
| } |
| |
| return nullptr; |
| } |
| |
| bool containsDiscardedTokens(const MatchFinder::MatchResult &Result, |
| CharSourceRange CharRange) { |
| std::string ReplacementText = |
| Lexer::getSourceText(CharRange, *Result.SourceManager, |
| Result.Context->getLangOpts()) |
| .str(); |
| Lexer Lex(CharRange.getBegin(), Result.Context->getLangOpts(), |
| ReplacementText.data(), ReplacementText.data(), |
| ReplacementText.data() + ReplacementText.size()); |
| Lex.SetCommentRetentionState(true); |
| |
| Token Tok; |
| while (!Lex.LexFromRawLexer(Tok)) { |
| if (Tok.is(tok::TokenKind::comment) || Tok.is(tok::TokenKind::hash)) |
| return true; |
| } |
| |
| return false; |
| } |
| |
| } // namespace |
| |
| class SimplifyBooleanExprCheck::Visitor : public RecursiveASTVisitor<Visitor> { |
| using Base = RecursiveASTVisitor<Visitor>; |
| |
| public: |
| Visitor(SimplifyBooleanExprCheck *Check, |
| const MatchFinder::MatchResult &Result) |
| : Check(Check), Result(Result) {} |
| |
| bool VisitBinaryOperator(BinaryOperator *Op) { |
| Check->reportBinOp(Result, Op); |
| return true; |
| } |
| |
| private: |
| SimplifyBooleanExprCheck *Check; |
| const MatchFinder::MatchResult &Result; |
| }; |
| |
| |
| SimplifyBooleanExprCheck::SimplifyBooleanExprCheck(StringRef Name, |
| ClangTidyContext *Context) |
| : ClangTidyCheck(Name, Context), |
| ChainedConditionalReturn(Options.get("ChainedConditionalReturn", 0U)), |
| ChainedConditionalAssignment( |
| Options.get("ChainedConditionalAssignment", 0U)) {} |
| |
| bool containsBoolLiteral(const Expr *E) { |
| if (!E) |
| return false; |
| E = E->IgnoreParenImpCasts(); |
| if (isa<CXXBoolLiteralExpr>(E)) |
| return true; |
| if (const auto *BinOp = dyn_cast<BinaryOperator>(E)) |
| return containsBoolLiteral(BinOp->getLHS()) || |
| containsBoolLiteral(BinOp->getRHS()); |
| if (const auto *UnaryOp = dyn_cast<UnaryOperator>(E)) |
| return containsBoolLiteral(UnaryOp->getSubExpr()); |
| return false; |
| } |
| |
| void SimplifyBooleanExprCheck::reportBinOp( |
| const MatchFinder::MatchResult &Result, const BinaryOperator *Op) { |
| const auto *LHS = Op->getLHS()->IgnoreParenImpCasts(); |
| const auto *RHS = Op->getRHS()->IgnoreParenImpCasts(); |
| |
| const CXXBoolLiteralExpr *Bool = nullptr; |
| const Expr *Other = nullptr; |
| if ((Bool = dyn_cast<CXXBoolLiteralExpr>(LHS))) |
| Other = RHS; |
| else if ((Bool = dyn_cast<CXXBoolLiteralExpr>(RHS))) |
| Other = LHS; |
| else |
| return; |
| |
| if (Bool->getLocStart().isMacroID()) |
| return; |
| |
| // FIXME: why do we need this? |
| if (!isa<CXXBoolLiteralExpr>(Other) && containsBoolLiteral(Other)) |
| return; |
| |
| bool BoolValue = Bool->getValue(); |
| |
| auto replaceWithExpression = [this, &Result, LHS, RHS, Bool]( |
| const Expr *ReplaceWith, bool Negated) { |
| std::string Replacement = |
| replacementExpression(Result, Negated, ReplaceWith); |
| SourceRange Range(LHS->getLocStart(), RHS->getLocEnd()); |
| issueDiag(Result, Bool->getLocStart(), SimplifyOperatorDiagnostic, Range, |
| Replacement); |
| }; |
| |
| switch (Op->getOpcode()) { |
| case BO_LAnd: |
| if (BoolValue) { |
| // expr && true -> expr |
| replaceWithExpression(Other, /*Negated=*/false); |
| } else { |
| // expr && false -> false |
| replaceWithExpression(Bool, /*Negated=*/false); |
| } |
| break; |
| case BO_LOr: |
| if (BoolValue) { |
| // expr || true -> true |
| replaceWithExpression(Bool, /*Negated=*/false); |
| } else { |
| // expr || false -> expr |
| replaceWithExpression(Other, /*Negated=*/false); |
| } |
| break; |
| case BO_EQ: |
| // expr == true -> expr, expr == false -> !expr |
| replaceWithExpression(Other, /*Negated=*/!BoolValue); |
| break; |
| case BO_NE: |
| // expr != true -> !expr, expr != false -> expr |
| replaceWithExpression(Other, /*Negated=*/BoolValue); |
| break; |
| default: |
| break; |
| } |
| } |
| |
| void SimplifyBooleanExprCheck::matchBoolCondition(MatchFinder *Finder, |
| bool Value, |
| StringRef BooleanId) { |
| Finder->addMatcher( |
| ifStmt(isExpansionInMainFile(), |
| hasCondition(cxxBoolLiteral(equals(Value)).bind(BooleanId))) |
| .bind(IfStmtId), |
| this); |
| } |
| |
| void SimplifyBooleanExprCheck::matchTernaryResult(MatchFinder *Finder, |
| bool Value, |
| StringRef TernaryId) { |
| Finder->addMatcher( |
| conditionalOperator(isExpansionInMainFile(), |
| hasTrueExpression(cxxBoolLiteral(equals(Value))), |
| hasFalseExpression(cxxBoolLiteral(equals(!Value)))) |
| .bind(TernaryId), |
| this); |
| } |
| |
| void SimplifyBooleanExprCheck::matchIfReturnsBool(MatchFinder *Finder, |
| bool Value, StringRef Id) { |
| if (ChainedConditionalReturn) |
| Finder->addMatcher(ifStmt(isExpansionInMainFile(), |
| hasThen(returnsBool(Value, ThenLiteralId)), |
| hasElse(returnsBool(!Value))) |
| .bind(Id), |
| this); |
| else |
| Finder->addMatcher(ifStmt(isExpansionInMainFile(), |
| unless(hasParent(ifStmt())), |
| hasThen(returnsBool(Value, ThenLiteralId)), |
| hasElse(returnsBool(!Value))) |
| .bind(Id), |
| this); |
| } |
| |
| void SimplifyBooleanExprCheck::matchIfAssignsBool(MatchFinder *Finder, |
| bool Value, StringRef Id) { |
| auto SimpleThen = binaryOperator( |
| hasOperatorName("="), |
| hasLHS(declRefExpr(hasDeclaration(decl().bind(IfAssignObjId)))), |
| hasLHS(expr().bind(IfAssignVariableId)), |
| hasRHS(cxxBoolLiteral(equals(Value)).bind(IfAssignLocId))); |
| auto Then = anyOf(SimpleThen, compoundStmt(statementCountIs(1), |
| hasAnySubstatement(SimpleThen))); |
| auto SimpleElse = binaryOperator( |
| hasOperatorName("="), |
| hasLHS(declRefExpr(hasDeclaration(equalsBoundNode(IfAssignObjId)))), |
| hasRHS(cxxBoolLiteral(equals(!Value)))); |
| auto Else = anyOf(SimpleElse, compoundStmt(statementCountIs(1), |
| hasAnySubstatement(SimpleElse))); |
| if (ChainedConditionalAssignment) |
| Finder->addMatcher( |
| ifStmt(isExpansionInMainFile(), hasThen(Then), hasElse(Else)).bind(Id), |
| this); |
| else |
| Finder->addMatcher(ifStmt(isExpansionInMainFile(), |
| unless(hasParent(ifStmt())), hasThen(Then), |
| hasElse(Else)) |
| .bind(Id), |
| this); |
| } |
| |
| void SimplifyBooleanExprCheck::matchCompoundIfReturnsBool(MatchFinder *Finder, |
| bool Value, |
| StringRef Id) { |
| Finder->addMatcher( |
| compoundStmt(allOf(hasAnySubstatement(ifStmt(hasThen(returnsBool(Value)), |
| unless(hasElse(stmt())))), |
| hasAnySubstatement( |
| returnStmt(has(ignoringParenImpCasts( |
| cxxBoolLiteral(equals(!Value))))) |
| .bind(CompoundReturnId)))) |
| .bind(Id), |
| this); |
| } |
| |
| void SimplifyBooleanExprCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) { |
| Options.store(Opts, "ChainedConditionalReturn", ChainedConditionalReturn); |
| Options.store(Opts, "ChainedConditionalAssignment", |
| ChainedConditionalAssignment); |
| } |
| |
| void SimplifyBooleanExprCheck::registerMatchers(MatchFinder *Finder) { |
| Finder->addMatcher(translationUnitDecl().bind("top"), this); |
| |
| matchBoolCondition(Finder, true, ConditionThenStmtId); |
| matchBoolCondition(Finder, false, ConditionElseStmtId); |
| |
| matchTernaryResult(Finder, true, TernaryId); |
| matchTernaryResult(Finder, false, TernaryNegatedId); |
| |
| matchIfReturnsBool(Finder, true, IfReturnsBoolId); |
| matchIfReturnsBool(Finder, false, IfReturnsNotBoolId); |
| |
| matchIfAssignsBool(Finder, true, IfAssignBoolId); |
| matchIfAssignsBool(Finder, false, IfAssignNotBoolId); |
| |
| matchCompoundIfReturnsBool(Finder, true, CompoundBoolId); |
| matchCompoundIfReturnsBool(Finder, false, CompoundNotBoolId); |
| } |
| |
| void SimplifyBooleanExprCheck::check(const MatchFinder::MatchResult &Result) { |
| if (const CXXBoolLiteralExpr *TrueConditionRemoved = |
| getBoolLiteral(Result, ConditionThenStmtId)) |
| replaceWithThenStatement(Result, TrueConditionRemoved); |
| else if (const CXXBoolLiteralExpr *FalseConditionRemoved = |
| getBoolLiteral(Result, ConditionElseStmtId)) |
| replaceWithElseStatement(Result, FalseConditionRemoved); |
| else if (const auto *Ternary = |
| Result.Nodes.getNodeAs<ConditionalOperator>(TernaryId)) |
| replaceWithCondition(Result, Ternary); |
| else if (const auto *TernaryNegated = |
| Result.Nodes.getNodeAs<ConditionalOperator>(TernaryNegatedId)) |
| replaceWithCondition(Result, TernaryNegated, true); |
| else if (const auto *If = Result.Nodes.getNodeAs<IfStmt>(IfReturnsBoolId)) |
| replaceWithReturnCondition(Result, If); |
| else if (const auto *IfNot = |
| Result.Nodes.getNodeAs<IfStmt>(IfReturnsNotBoolId)) |
| replaceWithReturnCondition(Result, IfNot, true); |
| else if (const auto *IfAssign = |
| Result.Nodes.getNodeAs<IfStmt>(IfAssignBoolId)) |
| replaceWithAssignment(Result, IfAssign); |
| else if (const auto *IfAssignNot = |
| Result.Nodes.getNodeAs<IfStmt>(IfAssignNotBoolId)) |
| replaceWithAssignment(Result, IfAssignNot, true); |
| else if (const auto *Compound = |
| Result.Nodes.getNodeAs<CompoundStmt>(CompoundBoolId)) |
| replaceCompoundReturnWithCondition(Result, Compound); |
| else if (const auto *Compound = |
| Result.Nodes.getNodeAs<CompoundStmt>(CompoundNotBoolId)) |
| replaceCompoundReturnWithCondition(Result, Compound, true); |
| else if (const auto TU = Result.Nodes.getNodeAs<Decl>("top")) |
| Visitor(this, Result).TraverseDecl(const_cast<Decl*>(TU)); |
| } |
| |
| void SimplifyBooleanExprCheck::issueDiag( |
| const ast_matchers::MatchFinder::MatchResult &Result, SourceLocation Loc, |
| StringRef Description, SourceRange ReplacementRange, |
| StringRef Replacement) { |
| CharSourceRange CharRange = |
| Lexer::makeFileCharRange(CharSourceRange::getTokenRange(ReplacementRange), |
| *Result.SourceManager, getLangOpts()); |
| |
| DiagnosticBuilder Diag = diag(Loc, Description); |
| if (!containsDiscardedTokens(Result, CharRange)) |
| Diag << FixItHint::CreateReplacement(CharRange, Replacement); |
| } |
| |
| void SimplifyBooleanExprCheck::replaceWithThenStatement( |
| const MatchFinder::MatchResult &Result, |
| const CXXBoolLiteralExpr *TrueConditionRemoved) { |
| const auto *IfStatement = Result.Nodes.getNodeAs<IfStmt>(IfStmtId); |
| issueDiag(Result, TrueConditionRemoved->getLocStart(), |
| SimplifyConditionDiagnostic, IfStatement->getSourceRange(), |
| getText(Result, *IfStatement->getThen())); |
| } |
| |
| void SimplifyBooleanExprCheck::replaceWithElseStatement( |
| const MatchFinder::MatchResult &Result, |
| const CXXBoolLiteralExpr *FalseConditionRemoved) { |
| const auto *IfStatement = Result.Nodes.getNodeAs<IfStmt>(IfStmtId); |
| const Stmt *ElseStatement = IfStatement->getElse(); |
| issueDiag(Result, FalseConditionRemoved->getLocStart(), |
| SimplifyConditionDiagnostic, IfStatement->getSourceRange(), |
| ElseStatement ? getText(Result, *ElseStatement) : ""); |
| } |
| |
| void SimplifyBooleanExprCheck::replaceWithCondition( |
| const MatchFinder::MatchResult &Result, const ConditionalOperator *Ternary, |
| bool Negated) { |
| std::string Replacement = |
| replacementExpression(Result, Negated, Ternary->getCond()); |
| issueDiag(Result, Ternary->getTrueExpr()->getLocStart(), |
| "redundant boolean literal in ternary expression result", |
| Ternary->getSourceRange(), Replacement); |
| } |
| |
| void SimplifyBooleanExprCheck::replaceWithReturnCondition( |
| const MatchFinder::MatchResult &Result, const IfStmt *If, bool Negated) { |
| StringRef Terminator = isa<CompoundStmt>(If->getElse()) ? ";" : ""; |
| std::string Condition = replacementExpression(Result, Negated, If->getCond()); |
| std::string Replacement = ("return " + Condition + Terminator).str(); |
| SourceLocation Start = |
| Result.Nodes.getNodeAs<CXXBoolLiteralExpr>(ThenLiteralId)->getLocStart(); |
| issueDiag(Result, Start, SimplifyConditionalReturnDiagnostic, |
| If->getSourceRange(), Replacement); |
| } |
| |
| void SimplifyBooleanExprCheck::replaceCompoundReturnWithCondition( |
| const MatchFinder::MatchResult &Result, const CompoundStmt *Compound, |
| bool Negated) { |
| const auto *Ret = Result.Nodes.getNodeAs<ReturnStmt>(CompoundReturnId); |
| |
| // The body shouldn't be empty because the matcher ensures that it must |
| // contain at least two statements: |
| // 1) A `return` statement returning a boolean literal `false` or `true` |
| // 2) An `if` statement with no `else` clause that consists of a single |
| // `return` statement returning the opposite boolean literal `true` or |
| // `false`. |
| assert(Compound->size() >= 2); |
| const IfStmt *BeforeIf = nullptr; |
| CompoundStmt::const_body_iterator Current = Compound->body_begin(); |
| CompoundStmt::const_body_iterator After = Compound->body_begin(); |
| for (++After; After != Compound->body_end() && *Current != Ret; |
| ++Current, ++After) { |
| if (const auto *If = dyn_cast<IfStmt>(*Current)) { |
| if (const CXXBoolLiteralExpr *Lit = stmtReturnsBool(If, Negated)) { |
| if (*After == Ret) { |
| if (!ChainedConditionalReturn && BeforeIf) |
| continue; |
| |
| const Expr *Condition = If->getCond(); |
| std::string Replacement = |
| "return " + replacementExpression(Result, Negated, Condition); |
| issueDiag( |
| Result, Lit->getLocStart(), SimplifyConditionalReturnDiagnostic, |
| SourceRange(If->getLocStart(), Ret->getLocEnd()), Replacement); |
| return; |
| } |
| |
| BeforeIf = If; |
| } |
| } else { |
| BeforeIf = nullptr; |
| } |
| } |
| } |
| |
| void SimplifyBooleanExprCheck::replaceWithAssignment( |
| const MatchFinder::MatchResult &Result, const IfStmt *IfAssign, |
| bool Negated) { |
| SourceRange Range = IfAssign->getSourceRange(); |
| StringRef VariableName = |
| getText(Result, *Result.Nodes.getNodeAs<Expr>(IfAssignVariableId)); |
| StringRef Terminator = isa<CompoundStmt>(IfAssign->getElse()) ? ";" : ""; |
| std::string Condition = |
| replacementExpression(Result, Negated, IfAssign->getCond()); |
| std::string Replacement = |
| (VariableName + " = " + Condition + Terminator).str(); |
| SourceLocation Location = |
| Result.Nodes.getNodeAs<CXXBoolLiteralExpr>(IfAssignLocId)->getLocStart(); |
| issueDiag(Result, Location, |
| "redundant boolean literal in conditional assignment", Range, |
| Replacement); |
| } |
| |
| } // namespace readability |
| } // namespace tidy |
| } // namespace clang |
