| //===--- ElseAfterReturnCheck.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 "ElseAfterReturnCheck.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 readability { |
| |
| void ElseAfterReturnCheck::registerMatchers(MatchFinder *Finder) { |
| const auto InterruptsControlFlow = |
| stmt(anyOf(returnStmt().bind("return"), continueStmt().bind("continue"), |
| breakStmt().bind("break"), |
| expr(ignoringImplicit(cxxThrowExpr().bind("throw"))))); |
| Finder->addMatcher( |
| compoundStmt(forEach( |
| ifStmt(unless(isConstexpr()), |
| // FIXME: Explore alternatives for the |
| // `if (T x = ...) {... return; } else { <use x> }` |
| // pattern: |
| // * warn, but don't fix; |
| // * fix by pulling out the variable declaration out of |
| // the condition. |
| unless(hasConditionVariableStatement(anything())), |
| hasThen(stmt(anyOf(InterruptsControlFlow, |
| compoundStmt(has(InterruptsControlFlow))))), |
| hasElse(stmt().bind("else"))) |
| .bind("if"))), |
| this); |
| } |
| |
| void ElseAfterReturnCheck::check(const MatchFinder::MatchResult &Result) { |
| const auto *If = Result.Nodes.getNodeAs<IfStmt>("if"); |
| SourceLocation ElseLoc = If->getElseLoc(); |
| std::string ControlFlowInterruptor; |
| for (const auto *BindingName : {"return", "continue", "break", "throw"}) |
| if (Result.Nodes.getNodeAs<Stmt>(BindingName)) |
| ControlFlowInterruptor = BindingName; |
| |
| DiagnosticBuilder Diag = diag(ElseLoc, "do not use 'else' after '%0'") |
| << ControlFlowInterruptor; |
| Diag << tooling::fixit::createRemoval(ElseLoc); |
| |
| // FIXME: Removing the braces isn't always safe. Do a more careful analysis. |
| // FIXME: Change clang-format to correctly un-indent the code. |
| if (const auto *CS = Result.Nodes.getNodeAs<CompoundStmt>("else")) |
| Diag << tooling::fixit::createRemoval(CS->getLBracLoc()) |
| << tooling::fixit::createRemoval(CS->getRBracLoc()); |
| } |
| |
| } // namespace readability |
| } // namespace tidy |
| } // namespace clang |