clang-tools-extra/clangd/refactor/tweaks/RawStringLiteral.cpp

   1 //===--- RawStringLiteral.cpp ------------------------------------*- C++-*-===//
   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-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 #include "ParsedAST.h"
   9 #include "refactor/Tweak.h"
  10 #include "clang/AST/Stmt.h"
  11 #include "clang/Basic/LangOptions.h"
  12 #include "clang/Basic/SourceLocation.h"
  13 #include "clang/Basic/SourceManager.h"
  14 #include "clang/Tooling/Core/Replacement.h"
  15 #include "llvm/ADT/StringRef.h"
  16 #include "llvm/Support/Casting.h"
  17 #include "llvm/Support/Error.h"
  18
  19 namespace clang {
  20 namespace clangd {
  21 namespace {
  22 /// Converts a string literal to a raw string.
  23 /// Before:
  24 ///   printf("\"a\"\nb");
  25 ///          ^^^^^^^^^
  26 /// After:
  27 ///   printf(R"("a"
  28 /// b)");
  29 class RawStringLiteral : public Tweak {
  30 public:
  31   const char *id() const final;
  32
  33   bool prepare(const Selection &Inputs) override;
  34   Expected<Effect> apply(const Selection &Inputs) override;
  35   std::string title() const override { return "Convert to raw string"; }
  36   llvm::StringLiteral kind() const override {
  37     return CodeAction::REFACTOR_KIND;
  38   }
  39
  40 private:
  41   const clang::StringLiteral *Str = nullptr;
  42 };
  43
  44 REGISTER_TWEAK(RawStringLiteral)
  45
  46 static bool isNormalString(const StringLiteral &Str, SourceLocation Cursor,
  47                           SourceManager &SM) {
  48   // All chunks must be normal ASCII strings, not u8"..." etc.
  49   if (!Str.isOrdinary())
  50     return false;
  51   SourceLocation LastTokenBeforeCursor;
  52   for (auto I = Str.tokloc_begin(), E = Str.tokloc_end(); I != E; ++I) {
  53     if (I->isMacroID()) // No tokens in the string may be macro expansions.
  54       return false;
  55     if (SM.isBeforeInTranslationUnit(*I, Cursor) || *I == Cursor)
  56       LastTokenBeforeCursor = *I;
  57   }
  58   // Token we care about must be a normal "string": not raw, u8, etc.
  59   const char* Data = SM.getCharacterData(LastTokenBeforeCursor);
  60   return Data && *Data == '"';
  61 }
  62
  63 static bool needsRaw(llvm::StringRef Content) {
  64   return Content.find_first_of("\"\n\t") != StringRef::npos;
  65 }
  66
  67 static bool canBeRaw(llvm::StringRef Content) {
  68   for (char C : Content)
  69     if (!llvm::isPrint(C) && C != '\n' && C != '\t')
  70       return false;
  71   return !Content.contains(")\"");
  72 }
  73
  74 bool RawStringLiteral::prepare(const Selection &Inputs) {
  75   const SelectionTree::Node *N = Inputs.ASTSelection.commonAncestor();
  76   if (!N)
  77     return false;
  78   Str = dyn_cast_or_null<StringLiteral>(N->ASTNode.get<Stmt>());
  79   return Str &&
  80          isNormalString(*Str, Inputs.Cursor, Inputs.AST->getSourceManager()) &&
  81          needsRaw(Str->getBytes()) && canBeRaw(Str->getBytes());
  82 }
  83
  84 Expected<Tweak::Effect> RawStringLiteral::apply(const Selection &Inputs) {
  85   auto &SM = Inputs.AST->getSourceManager();
  86   auto Reps = tooling::Replacements(
  87       tooling::Replacement(SM, Str, ("R\"(" + Str->getBytes() + ")\"").str(),
  88                            Inputs.AST->getLangOpts()));
  89   return Effect::mainFileEdit(SM, std::move(Reps));
  90 }
  91
  92 } // namespace
  93 } // namespace clangd
  94 } // namespace clang