clang-tools  16.0.0git
IncludeOrderCheck.cpp
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1 //===--- IncludeOrderCheck.cpp - clang-tidy -------------------------------===//
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 "IncludeOrderCheck.h"
10 #include "clang/Frontend/CompilerInstance.h"
11 #include "clang/Lex/PPCallbacks.h"
12 #include "clang/Lex/Preprocessor.h"
13 #include "llvm/ADT/STLExtras.h"
14 
15 #include <map>
16 
17 namespace clang {
18 namespace tidy {
19 namespace llvm_check {
20 
21 namespace {
22 class IncludeOrderPPCallbacks : public PPCallbacks {
23 public:
24  explicit IncludeOrderPPCallbacks(ClangTidyCheck &Check,
25  const SourceManager &SM)
26  : LookForMainModule(true), Check(Check), SM(SM) {}
27 
28  void InclusionDirective(SourceLocation HashLoc, const Token &IncludeTok,
29  StringRef FileName, bool IsAngled,
30  CharSourceRange FilenameRange,
31  Optional<FileEntryRef> File, StringRef SearchPath,
32  StringRef RelativePath, const Module *Imported,
33  SrcMgr::CharacteristicKind FileType) override;
34  void EndOfMainFile() override;
35 
36 private:
37  struct IncludeDirective {
38  SourceLocation Loc; ///< '#' location in the include directive
39  CharSourceRange Range; ///< SourceRange for the file name
40  std::string Filename; ///< Filename as a string
41  bool IsAngled; ///< true if this was an include with angle brackets
42  bool IsMainModule; ///< true if this was the first include in a file
43  };
44 
45  typedef std::vector<IncludeDirective> FileIncludes;
46  std::map<clang::FileID, FileIncludes> IncludeDirectives;
47  bool LookForMainModule;
48 
49  ClangTidyCheck &Check;
50  const SourceManager &SM;
51 };
52 } // namespace
53 
54 void IncludeOrderCheck::registerPPCallbacks(const SourceManager &SM,
55  Preprocessor *PP,
56  Preprocessor *ModuleExpanderPP) {
57  PP->addPPCallbacks(::std::make_unique<IncludeOrderPPCallbacks>(*this, SM));
58 }
59 
60 static int getPriority(StringRef Filename, bool IsAngled, bool IsMainModule) {
61  // We leave the main module header at the top.
62  if (IsMainModule)
63  return 0;
64 
65  // LLVM and clang headers are in the penultimate position.
66  if (Filename.startswith("llvm/") || Filename.startswith("llvm-c/") ||
67  Filename.startswith("clang/") || Filename.startswith("clang-c/"))
68  return 2;
69 
70  // Put these between system and llvm headers to be consistent with LLVM
71  // clang-format style.
72  if (Filename.startswith("gtest/") || Filename.startswith("gmock/"))
73  return 3;
74 
75  // System headers are sorted to the end.
76  if (IsAngled)
77  return 4;
78 
79  // Other headers are inserted between the main module header and LLVM headers.
80  return 1;
81 }
82 
83 void IncludeOrderPPCallbacks::InclusionDirective(
84  SourceLocation HashLoc, const Token &IncludeTok, StringRef FileName,
85  bool IsAngled, CharSourceRange FilenameRange, Optional<FileEntryRef> File,
86  StringRef SearchPath, StringRef RelativePath, const Module *Imported,
87  SrcMgr::CharacteristicKind FileType) {
88  // We recognize the first include as a special main module header and want
89  // to leave it in the top position.
90  IncludeDirective ID = {HashLoc, FilenameRange, std::string(FileName),
91  IsAngled, false};
92  if (LookForMainModule && !IsAngled) {
93  ID.IsMainModule = true;
94  LookForMainModule = false;
95  }
96 
97  // Bucket the include directives by the id of the file they were declared in.
98  IncludeDirectives[SM.getFileID(HashLoc)].push_back(std::move(ID));
99 }
100 
101 void IncludeOrderPPCallbacks::EndOfMainFile() {
102  LookForMainModule = true;
103  if (IncludeDirectives.empty())
104  return;
105 
106  // TODO: find duplicated includes.
107 
108  // Form blocks of includes. We don't want to sort across blocks. This also
109  // implicitly makes us never reorder over #defines or #if directives.
110  // FIXME: We should be more careful about sorting below comments as we don't
111  // know if the comment refers to the next include or the whole block that
112  // follows.
113  for (auto &Bucket : IncludeDirectives) {
114  auto &FileDirectives = Bucket.second;
115  std::vector<unsigned> Blocks(1, 0);
116  for (unsigned I = 1, E = FileDirectives.size(); I != E; ++I)
117  if (SM.getExpansionLineNumber(FileDirectives[I].Loc) !=
118  SM.getExpansionLineNumber(FileDirectives[I - 1].Loc) + 1)
119  Blocks.push_back(I);
120  Blocks.push_back(FileDirectives.size()); // Sentinel value.
121 
122  // Get a vector of indices.
123  std::vector<unsigned> IncludeIndices;
124  for (unsigned I = 0, E = FileDirectives.size(); I != E; ++I)
125  IncludeIndices.push_back(I);
126 
127  // Sort the includes. We first sort by priority, then lexicographically.
128  for (unsigned BI = 0, BE = Blocks.size() - 1; BI != BE; ++BI)
129  llvm::sort(IncludeIndices.begin() + Blocks[BI],
130  IncludeIndices.begin() + Blocks[BI + 1],
131  [&FileDirectives](unsigned LHSI, unsigned RHSI) {
132  IncludeDirective &LHS = FileDirectives[LHSI];
133  IncludeDirective &RHS = FileDirectives[RHSI];
134 
135  int PriorityLHS = getPriority(LHS.Filename, LHS.IsAngled,
136  LHS.IsMainModule);
137  int PriorityRHS = getPriority(RHS.Filename, RHS.IsAngled,
138  RHS.IsMainModule);
139 
140  return std::tie(PriorityLHS, LHS.Filename) <
141  std::tie(PriorityRHS, RHS.Filename);
142  });
143 
144  // Emit a warning for each block and fixits for all changes within that
145  // block.
146  for (unsigned BI = 0, BE = Blocks.size() - 1; BI != BE; ++BI) {
147  // Find the first include that's not in the right position.
148  unsigned I, E;
149  for (I = Blocks[BI], E = Blocks[BI + 1]; I != E; ++I)
150  if (IncludeIndices[I] != I)
151  break;
152 
153  if (I == E)
154  continue;
155 
156  // Emit a warning.
157  auto D = Check.diag(FileDirectives[I].Loc,
158  "#includes are not sorted properly");
159 
160  // Emit fix-its for all following includes in this block.
161  for (; I != E; ++I) {
162  if (IncludeIndices[I] == I)
163  continue;
164  const IncludeDirective &CopyFrom = FileDirectives[IncludeIndices[I]];
165 
166  SourceLocation FromLoc = CopyFrom.Range.getBegin();
167  const char *FromData = SM.getCharacterData(FromLoc);
168  unsigned FromLen = std::strcspn(FromData, "\n");
169 
170  StringRef FixedName(FromData, FromLen);
171 
172  SourceLocation ToLoc = FileDirectives[I].Range.getBegin();
173  const char *ToData = SM.getCharacterData(ToLoc);
174  unsigned ToLen = std::strcspn(ToData, "\n");
175  auto ToRange =
176  CharSourceRange::getCharRange(ToLoc, ToLoc.getLocWithOffset(ToLen));
177 
178  D << FixItHint::CreateReplacement(ToRange, FixedName);
179  }
180  }
181  }
182 
183  IncludeDirectives.clear();
184 }
185 
186 } // namespace llvm_check
187 } // namespace tidy
188 } // namespace clang
Range
CharSourceRange Range
SourceRange for the file name.
Definition: IncludeOrderCheck.cpp:39
E
const Expr * E
Definition: AvoidBindCheck.cpp:88
Filename
std::string Filename
Filename as a string.
Definition: IncludeOrderCheck.cpp:40
IncludeOrderCheck.h
clang::tidy::llvm_check::IncludeOrderCheck::registerPPCallbacks
void registerPPCallbacks(const SourceManager &SM, Preprocessor *PP, Preprocessor *ModuleExpanderPP) override
Override this to register PPCallbacks in the preprocessor.
Definition: IncludeOrderCheck.cpp:54
ns1::ns2::D
@ D
Definition: CategoricalFeature.h:3
FileName
StringRef FileName
Definition: KernelNameRestrictionCheck.cpp:46
clang::tidy::bugprone::PP
static Preprocessor * PP
Definition: BadSignalToKillThreadCheck.cpp:29
IsAngled
bool IsAngled
true if this was an include with angle brackets
Definition: IncludeOrderCheck.cpp:41
ID
static char ID
Definition: Logger.cpp:74
PPCallbacks
clang
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
Definition: ApplyReplacements.h:27
Loc
SourceLocation Loc
'#' location in the include directive
Definition: IncludeOrderCheck.cpp:38
clang::tidy::llvm_check::getPriority
static int getPriority(StringRef Filename, bool IsAngled, bool IsMainModule)
Definition: IncludeOrderCheck.cpp:60
IsMainModule
bool IsMainModule
true if this was the first include in a file
Definition: IncludeOrderCheck.cpp:42