117 lines · cpp
1//===--- SourceExtraction.cpp - Clang refactoring library -----------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "clang/Tooling/Refactoring/Extract/SourceExtraction.h"10#include "clang/AST/Stmt.h"11#include "clang/AST/StmtCXX.h"12#include "clang/AST/StmtObjC.h"13#include "clang/Basic/SourceManager.h"14#include "clang/Lex/Lexer.h"15#include <optional>16 17using namespace clang;18 19namespace {20 21/// Returns true if the token at the given location is a semicolon.22bool isSemicolonAtLocation(SourceLocation TokenLoc, const SourceManager &SM,23 const LangOptions &LangOpts) {24 return Lexer::getSourceText(25 CharSourceRange::getTokenRange(TokenLoc, TokenLoc), SM,26 LangOpts) == ";";27}28 29/// Returns true if there should be a semicolon after the given statement.30bool isSemicolonRequiredAfter(const Stmt *S) {31 if (isa<CompoundStmt>(S))32 return false;33 if (const auto *If = dyn_cast<IfStmt>(S))34 return isSemicolonRequiredAfter(If->getElse() ? If->getElse()35 : If->getThen());36 if (const auto *While = dyn_cast<WhileStmt>(S))37 return isSemicolonRequiredAfter(While->getBody());38 if (const auto *For = dyn_cast<ForStmt>(S))39 return isSemicolonRequiredAfter(For->getBody());40 if (const auto *CXXFor = dyn_cast<CXXForRangeStmt>(S))41 return isSemicolonRequiredAfter(CXXFor->getBody());42 if (const auto *ObjCFor = dyn_cast<ObjCForCollectionStmt>(S))43 return isSemicolonRequiredAfter(ObjCFor->getBody());44 if(const auto *Switch = dyn_cast<SwitchStmt>(S))45 return isSemicolonRequiredAfter(Switch->getBody());46 if(const auto *Case = dyn_cast<SwitchCase>(S))47 return isSemicolonRequiredAfter(Case->getSubStmt());48 switch (S->getStmtClass()) {49 case Stmt::DeclStmtClass:50 case Stmt::CXXTryStmtClass:51 case Stmt::ObjCAtSynchronizedStmtClass:52 case Stmt::ObjCAutoreleasePoolStmtClass:53 case Stmt::ObjCAtTryStmtClass:54 return false;55 default:56 return true;57 }58}59 60/// Returns true if the two source locations are on the same line.61bool areOnSameLine(SourceLocation Loc1, SourceLocation Loc2,62 const SourceManager &SM) {63 return !Loc1.isMacroID() && !Loc2.isMacroID() &&64 SM.getSpellingLineNumber(Loc1) == SM.getSpellingLineNumber(Loc2);65}66 67} // end anonymous namespace68 69namespace clang {70namespace tooling {71 72ExtractionSemicolonPolicy73ExtractionSemicolonPolicy::compute(const Stmt *S, SourceRange &ExtractedRange,74 const SourceManager &SM,75 const LangOptions &LangOpts) {76 auto neededInExtractedFunction = []() {77 return ExtractionSemicolonPolicy(true, false);78 };79 auto neededInOriginalFunction = []() {80 return ExtractionSemicolonPolicy(false, true);81 };82 83 /// The extracted expression should be terminated with a ';'. The call to84 /// the extracted function will replace this expression, so it won't need85 /// a terminating ';'.86 if (isa<Expr>(S))87 return neededInExtractedFunction();88 89 /// Some statements don't need to be terminated with ';'. The call to the90 /// extracted function will be a standalone statement, so it should be91 /// terminated with a ';'.92 bool NeedsSemi = isSemicolonRequiredAfter(S);93 if (!NeedsSemi)94 return neededInOriginalFunction();95 96 /// Some statements might end at ';'. The extraction will move that ';', so97 /// the call to the extracted function should be terminated with a ';'.98 SourceLocation End = ExtractedRange.getEnd();99 if (isSemicolonAtLocation(End, SM, LangOpts))100 return neededInOriginalFunction();101 102 /// Other statements should generally have a trailing ';'. We can try to find103 /// it and move it together it with the extracted code.104 std::optional<Token> NextToken = Lexer::findNextToken(End, SM, LangOpts);105 if (NextToken && NextToken->is(tok::semi) &&106 areOnSameLine(NextToken->getLocation(), End, SM)) {107 ExtractedRange.setEnd(NextToken->getLocation());108 return neededInOriginalFunction();109 }110 111 /// Otherwise insert semicolons in both places.112 return ExtractionSemicolonPolicy(true, true);113}114 115} // end namespace tooling116} // end namespace clang117