1//===--- AtomicChange.cpp - AtomicChange implementation -----------------*- 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
9#include "clang/Tooling/Refactoring/AtomicChange.h"
10#include "clang/Tooling/ReplacementsYaml.h"
11#include "llvm/Support/YAMLTraits.h"
12#include <string>
13
14LLVM_YAML_IS_SEQUENCE_VECTOR(clang::tooling::AtomicChange)
15
16namespace {
17/// Helper to (de)serialize an AtomicChange since we don't have direct
18/// access to its data members.
19/// Data members of a normalized AtomicChange can be directly mapped from/to
20/// YAML string.
21struct NormalizedAtomicChange {
22  NormalizedAtomicChange() = default;
23
24  NormalizedAtomicChange(const llvm::yaml::IO &) {}
25
26  // This converts AtomicChange's internal implementation of the replacements
27  // set to a vector of replacements.
28  NormalizedAtomicChange(const llvm::yaml::IO &,
29                         const clang::tooling::AtomicChange &E)
30      : Key(E.getKey()), FilePath(E.getFilePath()), Error(E.getError()),
31        InsertedHeaders(E.getInsertedHeaders()),
32        RemovedHeaders(E.getRemovedHeaders()),
33        Replaces(E.getReplacements().begin(), E.getReplacements().end()) {}
34
35  // This is not expected to be called but needed for template instantiation.
36  clang::tooling::AtomicChange denormalize(const llvm::yaml::IO &) {
37    llvm_unreachable("Do not convert YAML to AtomicChange directly with '>>'. "
38                     "Use AtomicChange::convertFromYAML instead.");
39  }
40  std::string Key;
41  std::string FilePath;
42  std::string Error;
43  std::vector<std::string> InsertedHeaders;
44  std::vector<std::string> RemovedHeaders;
45  std::vector<clang::tooling::Replacement> Replaces;
46};
47} // anonymous namespace
48
49namespace llvm {
50namespace yaml {
51
52/// Specialized MappingTraits to describe how an AtomicChange is
53/// (de)serialized.
54template <> struct MappingTraits<NormalizedAtomicChange> {
55  static void mapping(IO &Io, NormalizedAtomicChange &Doc) {
56    Io.mapRequired("Key", Doc.Key);
57    Io.mapRequired("FilePath", Doc.FilePath);
58    Io.mapRequired("Error", Doc.Error);
59    Io.mapRequired("InsertedHeaders", Doc.InsertedHeaders);
60    Io.mapRequired("RemovedHeaders", Doc.RemovedHeaders);
61    Io.mapRequired("Replacements", Doc.Replaces);
62  }
63};
64
65/// Specialized MappingTraits to describe how an AtomicChange is
66/// (de)serialized.
67template <> struct MappingTraits<clang::tooling::AtomicChange> {
68  static void mapping(IO &Io, clang::tooling::AtomicChange &Doc) {
69    MappingNormalization<NormalizedAtomicChange, clang::tooling::AtomicChange>
70        Keys(Io, Doc);
71    Io.mapRequired("Key", Keys->Key);
72    Io.mapRequired("FilePath", Keys->FilePath);
73    Io.mapRequired("Error", Keys->Error);
74    Io.mapRequired("InsertedHeaders", Keys->InsertedHeaders);
75    Io.mapRequired("RemovedHeaders", Keys->RemovedHeaders);
76    Io.mapRequired("Replacements", Keys->Replaces);
77  }
78};
79
80} // end namespace yaml
81} // end namespace llvm
82
83namespace clang {
84namespace tooling {
85namespace {
86
87// Returns true if there is any line that violates \p ColumnLimit in range
88// [Start, End].
89bool violatesColumnLimit(llvm::StringRef Code, unsigned ColumnLimit,
90                         unsigned Start, unsigned End) {
91  auto StartPos = Code.rfind('\n', Start);
92  StartPos = (StartPos == llvm::StringRef::npos) ? 0 : StartPos + 1;
93
94  auto EndPos = Code.find("\n", End);
95  if (EndPos == llvm::StringRef::npos)
96    EndPos = Code.size();
97
98  llvm::SmallVector<llvm::StringRef, 8> Lines;
99  Code.substr(StartPos, EndPos - StartPos).split(Lines, '\n');
100  for (llvm::StringRef Line : Lines)
101    if (Line.size() > ColumnLimit)
102      return true;
103  return false;
104}
105
106std::vector<Range>
107getRangesForFormating(llvm::StringRef Code, unsigned ColumnLimit,
108                      ApplyChangesSpec::FormatOption Format,
109                      const clang::tooling::Replacements &Replaces) {
110  // kNone suppresses formatting entirely.
111  if (Format == ApplyChangesSpec::kNone)
112    return {};
113  std::vector<clang::tooling::Range> Ranges;
114  // This works assuming that replacements are ordered by offset.
115  // FIXME: use `getAffectedRanges()` to calculate when it does not include '\n'
116  // at the end of an insertion in affected ranges.
117  int Offset = 0;
118  for (const clang::tooling::Replacement &R : Replaces) {
119    int Start = R.getOffset() + Offset;
120    int End = Start + R.getReplacementText().size();
121    if (!R.getReplacementText().empty() &&
122        R.getReplacementText().back() == '\n' && R.getLength() == 0 &&
123        R.getOffset() > 0 && R.getOffset() <= Code.size() &&
124        Code[R.getOffset() - 1] == '\n')
125      // If we are inserting at the start of a line and the replacement ends in
126      // a newline, we don't need to format the subsequent line.
127      --End;
128    Offset += R.getReplacementText().size() - R.getLength();
129
130    if (Format == ApplyChangesSpec::kAll ||
131        violatesColumnLimit(Code, ColumnLimit, Start, End))
132      Ranges.emplace_back(Start, End - Start);
133  }
134  return Ranges;
135}
136
137inline llvm::Error make_string_error(const llvm::Twine &Message) {
138  return llvm::make_error<llvm::StringError>(Message,
139                                             llvm::inconvertibleErrorCode());
140}
141
142// Creates replacements for inserting/deleting #include headers.
143llvm::Expected<Replacements>
144createReplacementsForHeaders(llvm::StringRef FilePath, llvm::StringRef Code,
145                             llvm::ArrayRef<AtomicChange> Changes,
146                             const format::FormatStyle &Style) {
147  // Create header insertion/deletion replacements to be cleaned up
148  // (i.e. converted to real insertion/deletion replacements).
149  Replacements HeaderReplacements;
150  for (const auto &Change : Changes) {
151    for (llvm::StringRef Header : Change.getInsertedHeaders()) {
152      std::string EscapedHeader =
153          Header.startswith("<") || Header.startswith("\"")
154              ? Header.str()
155              : ("\"" + Header + "\"").str();
156      std::string ReplacementText = "#include " + EscapedHeader;
157      // Offset UINT_MAX and length 0 indicate that the replacement is a header
158      // insertion.
159      llvm::Error Err = HeaderReplacements.add(
160          tooling::Replacement(FilePath, UINT_MAX, 0, ReplacementText));
161      if (Err)
162        return std::move(Err);
163    }
164    for (const std::string &Header : Change.getRemovedHeaders()) {
165      // Offset UINT_MAX and length 1 indicate that the replacement is a header
166      // deletion.
167      llvm::Error Err =
168          HeaderReplacements.add(Replacement(FilePath, UINT_MAX, 1, Header));
169      if (Err)
170        return std::move(Err);
171    }
172  }
173
174  // cleanupAroundReplacements() converts header insertions/deletions into
175  // actual replacements that add/remove headers at the right location.
176  return clang::format::cleanupAroundReplacements(Code, HeaderReplacements,
177                                                  Style);
178}
179
180// Combine replacements in all Changes as a `Replacements`. This ignores the
181// file path in all replacements and replaces them with \p FilePath.
182llvm::Expected<Replacements>
183combineReplacementsInChanges(llvm::StringRef FilePath,
184                             llvm::ArrayRef<AtomicChange> Changes) {
185  Replacements Replaces;
186  for (const auto &Change : Changes)
187    for (const auto &R : Change.getReplacements())
188      if (auto Err = Replaces.add(Replacement(
189              FilePath, R.getOffset(), R.getLength(), R.getReplacementText())))
190        return std::move(Err);
191  return Replaces;
192}
193
194} // end namespace
195
196AtomicChange::AtomicChange(const SourceManager &SM,
197                           SourceLocation KeyPosition) {
198  const FullSourceLoc FullKeyPosition(KeyPosition, SM);
199  std::pair<FileID, unsigned> FileIDAndOffset =
200      FullKeyPosition.getSpellingLoc().getDecomposedLoc();
201  const FileEntry *FE = SM.getFileEntryForID(FileIDAndOffset.first);
202  assert(FE && "Cannot create AtomicChange with invalid location.");
203  FilePath = FE->getName();
204  Key = FilePath + ":" + std::to_string(FileIDAndOffset.second);
205}
206
207AtomicChange::AtomicChange(std::string Key, std::string FilePath,
208                           std::string Error,
209                           std::vector<std::string> InsertedHeaders,
210                           std::vector<std::string> RemovedHeaders,
211                           clang::tooling::Replacements Replaces)
212    : Key(std::move(Key)), FilePath(std::move(FilePath)),
213      Error(std::move(Error)), InsertedHeaders(std::move(InsertedHeaders)),
214      RemovedHeaders(std::move(RemovedHeaders)), Replaces(std::move(Replaces)) {
215}
216
217bool AtomicChange::operator==(const AtomicChange &Other) const {
218  if (Key != Other.Key || FilePath != Other.FilePath || Error != Other.Error)
219    return false;
220  if (!(Replaces == Other.Replaces))
221    return false;
222  // FXIME: Compare header insertions/removals.
223  return true;
224}
225
226std::string AtomicChange::toYAMLString() {
227  std::string YamlContent;
228  llvm::raw_string_ostream YamlContentStream(YamlContent);
229
230  llvm::yaml::Output YAML(YamlContentStream);
231  YAML << *this;
232  YamlContentStream.flush();
233  return YamlContent;
234}
235
236AtomicChange AtomicChange::convertFromYAML(llvm::StringRef YAMLContent) {
237  NormalizedAtomicChange NE;
238  llvm::yaml::Input YAML(YAMLContent);
239  YAML >> NE;
240  AtomicChange E(NE.Key, NE.FilePath, NE.Error, NE.InsertedHeaders,
241                 NE.RemovedHeaders, tooling::Replacements());
242  for (const auto &R : NE.Replaces) {
243    llvm::Error Err = E.Replaces.add(R);
244    if (Err)
245      llvm_unreachable(
246          "Failed to add replacement when Converting YAML to AtomicChange.");
247    llvm::consumeError(std::move(Err));
248  }
249  return E;
250}
251
252llvm::Error AtomicChange::replace(const SourceManager &SM,
253                                  const CharSourceRange &Range,
254                                  llvm::StringRef ReplacementText) {
255  return Replaces.add(Replacement(SM, Range, ReplacementText));
256}
257
258llvm::Error AtomicChange::replace(const SourceManager &SM, SourceLocation Loc,
259                                  unsigned Length, llvm::StringRef Text) {
260  return Replaces.add(Replacement(SM, Loc, Length, Text));
261}
262
263llvm::Error AtomicChange::insert(const SourceManager &SM, SourceLocation Loc,
264                                 llvm::StringRef Text, bool InsertAfter) {
265  if (Text.empty())
266    return llvm::Error::success();
267  Replacement R(SM, Loc, 0, Text);
268  llvm::Error Err = Replaces.add(R);
269  if (Err) {
270    return llvm::handleErrors(
271        std::move(Err), [&](const ReplacementError &RE) -> llvm::Error {
272          if (RE.get() != replacement_error::insert_conflict)
273            return llvm::make_error<ReplacementError>(RE);
274          unsigned NewOffset = Replaces.getShiftedCodePosition(R.getOffset());
275          if (!InsertAfter)
276            NewOffset -=
277                RE.getExistingReplacement()->getReplacementText().size();
278          Replacement NewR(R.getFilePath(), NewOffset, 0, Text);
279          Replaces = Replaces.merge(Replacements(NewR));
280          return llvm::Error::success();
281        });
282  }
283  return llvm::Error::success();
284}
285
286void AtomicChange::addHeader(llvm::StringRef Header) {
287  InsertedHeaders.push_back(Header);
288}
289
290void AtomicChange::removeHeader(llvm::StringRef Header) {
291  RemovedHeaders.push_back(Header);
292}
293
294llvm::Expected<std::string>
295applyAtomicChanges(llvm::StringRef FilePath, llvm::StringRef Code,
296                   llvm::ArrayRef<AtomicChange> Changes,
297                   const ApplyChangesSpec &Spec) {
298  llvm::Expected<Replacements> HeaderReplacements =
299      createReplacementsForHeaders(FilePath, Code, Changes, Spec.Style);
300  if (!HeaderReplacements)
301    return make_string_error(
302        "Failed to create replacements for header changes: " +
303        llvm::toString(HeaderReplacements.takeError()));
304
305  llvm::Expected<Replacements> Replaces =
306      combineReplacementsInChanges(FilePath, Changes);
307  if (!Replaces)
308    return make_string_error("Failed to combine replacements in all changes: " +
309                             llvm::toString(Replaces.takeError()));
310
311  Replacements AllReplaces = std::move(*Replaces);
312  for (const auto &R : *HeaderReplacements) {
313    llvm::Error Err = AllReplaces.add(R);
314    if (Err)
315      return make_string_error(
316          "Failed to combine existing replacements with header replacements: " +
317          llvm::toString(std::move(Err)));
318  }
319
320  if (Spec.Cleanup) {
321    llvm::Expected<Replacements> CleanReplaces =
322        format::cleanupAroundReplacements(Code, AllReplaces, Spec.Style);
323    if (!CleanReplaces)
324      return make_string_error("Failed to cleanup around replacements: " +
325                               llvm::toString(CleanReplaces.takeError()));
326    AllReplaces = std::move(*CleanReplaces);
327  }
328
329  // Apply all replacements.
330  llvm::Expected<std::string> ChangedCode =
331      applyAllReplacements(Code, AllReplaces);
332  if (!ChangedCode)
333    return make_string_error("Failed to apply all replacements: " +
334                             llvm::toString(ChangedCode.takeError()));
335
336  // Sort inserted headers. This is done even if other formatting is turned off
337  // as incorrectly sorted headers are always just wrong, it's not a matter of
338  // taste.
339  Replacements HeaderSortingReplacements = format::sortIncludes(
340      Spec.Style, *ChangedCode, AllReplaces.getAffectedRanges(), FilePath);
341  ChangedCode = applyAllReplacements(*ChangedCode, HeaderSortingReplacements);
342  if (!ChangedCode)
343    return make_string_error(
344        "Failed to apply replacements for sorting includes: " +
345        llvm::toString(ChangedCode.takeError()));
346
347  AllReplaces = AllReplaces.merge(HeaderSortingReplacements);
348
349  std::vector<Range> FormatRanges = getRangesForFormating(
350      *ChangedCode, Spec.Style.ColumnLimit, Spec.Format, AllReplaces);
351  if (!FormatRanges.empty()) {
352    Replacements FormatReplacements =
353        format::reformat(Spec.Style, *ChangedCode, FormatRanges, FilePath);
354    ChangedCode = applyAllReplacements(*ChangedCode, FormatReplacements);
355    if (!ChangedCode)
356      return make_string_error(
357          "Failed to apply replacements for formatting changed code: " +
358          llvm::toString(ChangedCode.takeError()));
359  }
360  return ChangedCode;
361}
362
363} // end namespace tooling
364} // end namespace clang
365