clang-tools-extra/clangd/refactor/Tweak.cpp

   1 //===--- Tweak.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 "Tweak.h"
   9 #include "FeatureModule.h"
  10 #include "SourceCode.h"
  11 #include "index/Index.h"
  12 #include "support/Logger.h"
  13 #include "support/Path.h"
  14 #include "llvm/ADT/STLExtras.h"
  15 #include "llvm/ADT/StringMap.h"
  16 #include "llvm/ADT/StringRef.h"
  17 #include "llvm/Support/Error.h"
  18 #include "llvm/Support/Registry.h"
  19 #include <functional>
  20 #include <memory>
  21 #include <utility>
  22 #include <vector>
  23
  24 LLVM_INSTANTIATE_REGISTRY(llvm::Registry<clang::clangd::Tweak>)
  25
  26 namespace clang {
  27 namespace clangd {
  28
  29 /// A handy typedef to save some typing.
  30 typedef llvm::Registry<Tweak> TweakRegistry;
  31
  32 namespace {
  33 /// Asserts invariants on TweakRegistry. No-op with assertion disabled.
  34 void validateRegistry() {
  35 #ifndef NDEBUG
  36   llvm::StringSet<> Seen;
  37   for (const auto &E : TweakRegistry::entries()) {
  38     // REGISTER_TWEAK ensures E.getName() is equal to the tweak class name.
  39     // We check that id() matches it.
  40     assert(E.instantiate()->id() == E.getName() &&
  41            "id should be equal to class name");
  42     assert(Seen.try_emplace(E.getName()).second && "duplicate check id");
  43   }
  44 #endif
  45 }
  46
  47 std::vector<std::unique_ptr<Tweak>>
  48 getAllTweaks(const FeatureModuleSet *Modules) {
  49   std::vector<std::unique_ptr<Tweak>> All;
  50   for (const auto &E : TweakRegistry::entries())
  51     All.emplace_back(E.instantiate());
  52   if (Modules) {
  53     for (auto &M : *Modules)
  54       M.contributeTweaks(All);
  55   }
  56   return All;
  57 }
  58 } // namespace
  59
  60 Tweak::Selection::Selection(const SymbolIndex *Index, ParsedAST &AST,
  61                             unsigned RangeBegin, unsigned RangeEnd,
  62                             SelectionTree ASTSelection,
  63                             llvm::vfs::FileSystem *FS)
  64     : Index(Index), AST(&AST), SelectionBegin(RangeBegin),
  65       SelectionEnd(RangeEnd), ASTSelection(std::move(ASTSelection)), FS(FS) {
  66   auto &SM = AST.getSourceManager();
  67   Code = SM.getBufferData(SM.getMainFileID());
  68   Cursor = SM.getComposedLoc(SM.getMainFileID(), RangeBegin);
  69 }
  70
  71 std::vector<std::unique_ptr<Tweak>>
  72 prepareTweaks(const Tweak::Selection &S,
  73               llvm::function_ref<bool(const Tweak &)> Filter,
  74               const FeatureModuleSet *Modules) {
  75   validateRegistry();
  76
  77   std::vector<std::unique_ptr<Tweak>> Available;
  78   for (auto &T : getAllTweaks(Modules)) {
  79     if (!Filter(*T) || !T->prepare(S))
  80       continue;
  81     Available.push_back(std::move(T));
  82   }
  83   // Ensure deterministic order of the results.
  84   llvm::sort(Available,
  85              [](const std::unique_ptr<Tweak> &L,
  86                 const std::unique_ptr<Tweak> &R) { return L->id() < R->id(); });
  87   return Available;
  88 }
  89
  90 llvm::Expected<std::unique_ptr<Tweak>>
  91 prepareTweak(StringRef ID, const Tweak::Selection &S,
  92              const FeatureModuleSet *Modules) {
  93   for (auto &T : getAllTweaks(Modules)) {
  94     if (T->id() != ID)
  95       continue;
  96     if (!T->prepare(S))
  97       return error("failed to prepare() tweak {0}", ID);
  98     return std::move(T);
  99   }
 100   return error("tweak ID {0} is invalid", ID);
 101 }
 102
 103 llvm::Expected<std::pair<Path, Edit>>
 104 Tweak::Effect::fileEdit(const SourceManager &SM, FileID FID,
 105                         tooling::Replacements Replacements) {
 106   Edit Ed(SM.getBufferData(FID), std::move(Replacements));
 107   if (const auto FE = SM.getFileEntryRefForID(FID))
 108     if (auto FilePath = getCanonicalPath(*FE, SM.getFileManager()))
 109       return std::make_pair(*FilePath, std::move(Ed));
 110   return error("Failed to get absolute path for edited file: {0}",
 111                SM.getFileEntryRefForID(FID)->getName());
 112 }
 113
 114 llvm::Expected<Tweak::Effect>
 115 Tweak::Effect::mainFileEdit(const SourceManager &SM,
 116                             tooling::Replacements Replacements) {
 117   auto PathAndEdit = fileEdit(SM, SM.getMainFileID(), std::move(Replacements));
 118   if (!PathAndEdit)
 119     return PathAndEdit.takeError();
 120   Tweak::Effect E;
 121   E.ApplyEdits.try_emplace(PathAndEdit->first, PathAndEdit->second);
 122   return E;
 123 }
 124
 125 } // namespace clangd
 126 } // namespace clang