1 //===---------- IncludeSorter.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 "IncludeSorter.h"
10 #include "clang/Basic/SourceManager.h"
11 #include "clang/Lex/Lexer.h"
12 #include <algorithm>
13 
14 namespace clang {
15 namespace tidy {
16 namespace utils {
17 
18 namespace {
19 
RemoveFirstSuffix(StringRef Str,ArrayRef<const char * > Suffixes)20 StringRef RemoveFirstSuffix(StringRef Str, ArrayRef<const char *> Suffixes) {
21   for (StringRef Suffix : Suffixes) {
22     if (Str.endswith(Suffix)) {
23       return Str.substr(0, Str.size() - Suffix.size());
24     }
25   }
26   return Str;
27 }
28 
MakeCanonicalName(StringRef Str,IncludeSorter::IncludeStyle Style)29 StringRef MakeCanonicalName(StringRef Str, IncludeSorter::IncludeStyle Style) {
30   // The list of suffixes to remove from source file names to get the
31   // "canonical" file names.
32   // E.g. tools/sort_includes.cc and tools/sort_includes_test.cc
33   // would both canonicalize to tools/sort_includes and tools/sort_includes.h
34   // (once canonicalized) will match as being the main include file associated
35   // with the source files.
36   if (Style == IncludeSorter::IS_LLVM) {
37     return RemoveFirstSuffix(
38         RemoveFirstSuffix(Str, {".cc", ".cpp", ".c", ".h", ".hpp"}), {"Test"});
39   }
40   if (Style == IncludeSorter::IS_Google_ObjC) {
41     StringRef Canonical =
42         RemoveFirstSuffix(RemoveFirstSuffix(Str, {".cc", ".cpp", ".c", ".h",
43                                                   ".hpp", ".mm", ".m"}),
44                           {"_unittest", "_regtest", "_test", "Test"});
45 
46     // Objective-C categories have a `+suffix` format, but should be grouped
47     // with the file they are a category of.
48     size_t StartIndex = Canonical.find_last_of('/');
49     if (StartIndex == StringRef::npos) {
50       StartIndex = 0;
51     }
52     return Canonical.substr(
53         0, Canonical.find_first_of('+', StartIndex));
54   }
55   return RemoveFirstSuffix(
56       RemoveFirstSuffix(Str, {".cc", ".cpp", ".c", ".h", ".hpp"}),
57       {"_unittest", "_regtest", "_test"});
58 }
59 
60 // Scan to the end of the line and return the offset of the next line.
FindNextLine(const char * Text)61 size_t FindNextLine(const char *Text) {
62   size_t EOLIndex = std::strcspn(Text, "\n");
63   return Text[EOLIndex] == '\0' ? EOLIndex : EOLIndex + 1;
64 }
65 
66 IncludeSorter::IncludeKinds
DetermineIncludeKind(StringRef CanonicalFile,StringRef IncludeFile,bool IsAngled,IncludeSorter::IncludeStyle Style)67 DetermineIncludeKind(StringRef CanonicalFile, StringRef IncludeFile,
68                      bool IsAngled, IncludeSorter::IncludeStyle Style) {
69   // Compute the two "canonical" forms of the include's filename sans extension.
70   // The first form is the include's filename without ".h" or "-inl.h" at the
71   // end. The second form is the first form with "/public/" in the file path
72   // replaced by "/internal/".
73   if (IsAngled) {
74     // If the system include (<foo>) ends with ".h", then it is a normal C-style
75     // include. Otherwise assume it is a C++-style extensionless include.
76     return IncludeFile.endswith(".h") ? IncludeSorter::IK_CSystemInclude
77                                       : IncludeSorter::IK_CXXSystemInclude;
78   }
79   StringRef CanonicalInclude = MakeCanonicalName(IncludeFile, Style);
80   if (CanonicalFile.endswith(CanonicalInclude)
81       || CanonicalInclude.endswith(CanonicalFile)) {
82     return IncludeSorter::IK_MainTUInclude;
83   }
84   if ((Style == IncludeSorter::IS_Google) ||
85       (Style == IncludeSorter::IS_Google_ObjC)) {
86     std::pair<StringRef, StringRef> Parts = CanonicalInclude.split("/public/");
87     std::string AltCanonicalInclude =
88         Parts.first.str() + "/internal/" + Parts.second.str();
89     std::string ProtoCanonicalInclude =
90         Parts.first.str() + "/proto/" + Parts.second.str();
91 
92     // Determine the kind of this inclusion.
93     if (CanonicalFile.equals(AltCanonicalInclude) ||
94         CanonicalFile.equals(ProtoCanonicalInclude)) {
95       return IncludeSorter::IK_MainTUInclude;
96     }
97   }
98   if (Style == IncludeSorter::IS_Google_ObjC) {
99     if (IncludeFile.endswith(".generated.h") ||
100         IncludeFile.endswith(".proto.h") || IncludeFile.endswith(".pbobjc.h")) {
101       return IncludeSorter::IK_GeneratedInclude;
102     }
103   }
104   return IncludeSorter::IK_NonSystemInclude;
105 }
106 
compareHeaders(StringRef LHS,StringRef RHS,IncludeSorter::IncludeStyle Style)107 int compareHeaders(StringRef LHS, StringRef RHS,
108                    IncludeSorter::IncludeStyle Style) {
109   if (Style == IncludeSorter::IncludeStyle::IS_Google_ObjC) {
110     const std::pair<const char *, const char *> &Mismatch =
111         std::mismatch(LHS.begin(), LHS.end(), RHS.begin());
112     if ((Mismatch.first != LHS.end()) && (Mismatch.second != RHS.end())) {
113       if ((*Mismatch.first == '.') && (*Mismatch.second == '+')) {
114         return -1;
115       }
116       if ((*Mismatch.first == '+') && (*Mismatch.second == '.')) {
117         return 1;
118       }
119     }
120   }
121   return LHS.compare(RHS);
122 }
123 
124 } // namespace
125 
IncludeSorter(const SourceManager * SourceMgr,const FileID FileID,StringRef FileName,IncludeStyle Style)126 IncludeSorter::IncludeSorter(const SourceManager *SourceMgr,
127                              const FileID FileID, StringRef FileName,
128                              IncludeStyle Style)
129     : SourceMgr(SourceMgr), Style(Style), CurrentFileID(FileID),
130       CanonicalFile(MakeCanonicalName(FileName, Style)) {}
131 
AddInclude(StringRef FileName,bool IsAngled,SourceLocation HashLocation,SourceLocation EndLocation)132 void IncludeSorter::AddInclude(StringRef FileName, bool IsAngled,
133                                SourceLocation HashLocation,
134                                SourceLocation EndLocation) {
135   int Offset = FindNextLine(SourceMgr->getCharacterData(EndLocation));
136 
137   // Record the relevant location information for this inclusion directive.
138   IncludeLocations[FileName].push_back(
139       SourceRange(HashLocation, EndLocation.getLocWithOffset(Offset)));
140   SourceLocations.push_back(IncludeLocations[FileName].back());
141 
142   // Stop if this inclusion is a duplicate.
143   if (IncludeLocations[FileName].size() > 1)
144     return;
145 
146   // Add the included file's name to the appropriate bucket.
147   IncludeKinds Kind =
148       DetermineIncludeKind(CanonicalFile, FileName, IsAngled, Style);
149   if (Kind != IK_InvalidInclude)
150     IncludeBucket[Kind].push_back(FileName.str());
151 }
152 
CreateIncludeInsertion(StringRef FileName,bool IsAngled)153 Optional<FixItHint> IncludeSorter::CreateIncludeInsertion(StringRef FileName,
154                                                           bool IsAngled) {
155   std::string IncludeStmt;
156   if (Style == IncludeStyle::IS_Google_ObjC) {
157     IncludeStmt = IsAngled
158                       ? llvm::Twine("#import <" + FileName + ">\n").str()
159                       : llvm::Twine("#import \"" + FileName + "\"\n").str();
160   } else {
161     IncludeStmt = IsAngled
162                       ? llvm::Twine("#include <" + FileName + ">\n").str()
163                       : llvm::Twine("#include \"" + FileName + "\"\n").str();
164   }
165   if (SourceLocations.empty()) {
166     // If there are no includes in this file, add it in the first line.
167     // FIXME: insert after the file comment or the header guard, if present.
168     IncludeStmt.append("\n");
169     return FixItHint::CreateInsertion(
170         SourceMgr->getLocForStartOfFile(CurrentFileID), IncludeStmt);
171   }
172 
173   auto IncludeKind =
174       DetermineIncludeKind(CanonicalFile, FileName, IsAngled, Style);
175 
176   if (!IncludeBucket[IncludeKind].empty()) {
177     for (const std::string &IncludeEntry : IncludeBucket[IncludeKind]) {
178       if (compareHeaders(FileName, IncludeEntry, Style) < 0) {
179         const auto &Location = IncludeLocations[IncludeEntry][0];
180         return FixItHint::CreateInsertion(Location.getBegin(), IncludeStmt);
181       } else if (FileName == IncludeEntry) {
182         return llvm::None;
183       }
184     }
185     // FileName comes after all include entries in bucket, insert it after
186     // last.
187     const std::string &LastInclude = IncludeBucket[IncludeKind].back();
188     SourceRange LastIncludeLocation = IncludeLocations[LastInclude].back();
189     return FixItHint::CreateInsertion(LastIncludeLocation.getEnd(),
190                                       IncludeStmt);
191   }
192   // Find the non-empty include bucket to be sorted directly above
193   // 'IncludeKind'. If such a bucket exists, we'll want to sort the include
194   // after that bucket. If no such bucket exists, find the first non-empty
195   // include bucket in the file. In that case, we'll want to sort the include
196   // before that bucket.
197   IncludeKinds NonEmptyKind = IK_InvalidInclude;
198   for (int i = IK_InvalidInclude - 1; i >= 0; --i) {
199     if (!IncludeBucket[i].empty()) {
200       NonEmptyKind = static_cast<IncludeKinds>(i);
201       if (NonEmptyKind < IncludeKind)
202         break;
203     }
204   }
205   if (NonEmptyKind == IK_InvalidInclude) {
206     return llvm::None;
207   }
208 
209   if (NonEmptyKind < IncludeKind) {
210     // Create a block after.
211     const std::string &LastInclude = IncludeBucket[NonEmptyKind].back();
212     SourceRange LastIncludeLocation = IncludeLocations[LastInclude].back();
213     IncludeStmt = '\n' + IncludeStmt;
214     return FixItHint::CreateInsertion(LastIncludeLocation.getEnd(),
215                                       IncludeStmt);
216   }
217   // Create a block before.
218   const std::string &FirstInclude = IncludeBucket[NonEmptyKind][0];
219   SourceRange FirstIncludeLocation = IncludeLocations[FirstInclude].back();
220   IncludeStmt.append("\n");
221   return FixItHint::CreateInsertion(FirstIncludeLocation.getBegin(),
222                                     IncludeStmt);
223 }
224 
225 } // namespace utils
226 
227 llvm::ArrayRef<std::pair<utils::IncludeSorter::IncludeStyle, StringRef>>
getEnumMapping()228 OptionEnumMapping<utils::IncludeSorter::IncludeStyle>::getEnumMapping() {
229   static constexpr std::pair<utils::IncludeSorter::IncludeStyle, StringRef>
230       Mapping[] = {{utils::IncludeSorter::IS_LLVM, "llvm"},
231                    {utils::IncludeSorter::IS_Google, "google"},
232                    {utils::IncludeSorter::IS_Google_ObjC, "google-objc"}};
233   return makeArrayRef(Mapping);
234 }
235 } // namespace tidy
236 } // namespace clang
237