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