1 //===--- HeaderIncludes.h - Insert/Delete #includes for C++ code--*- 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 #ifndef LLVM_CLANG_TOOLING_INCLUSIONS_HEADERINCLUDES_H
10 #define LLVM_CLANG_TOOLING_INCLUSIONS_HEADERINCLUDES_H
11 
12 #include "clang/Basic/SourceManager.h"
13 #include "clang/Tooling/Core/Replacement.h"
14 #include "clang/Tooling/Inclusions/IncludeStyle.h"
15 #include "llvm/Support/Path.h"
16 #include "llvm/Support/Regex.h"
17 #include <list>
18 #include <unordered_map>
19 
20 namespace clang {
21 namespace tooling {
22 
23 /// This class manages priorities of C++ #include categories and calculates
24 /// priorities for headers.
25 /// FIXME(ioeric): move this class into implementation file when clang-format's
26 /// include sorting functions are also moved here.
27 class IncludeCategoryManager {
28 public:
29   IncludeCategoryManager(const IncludeStyle &Style, StringRef FileName);
30 
31   /// Returns the priority of the category which \p IncludeName belongs to.
32   /// If \p CheckMainHeader is true and \p IncludeName is a main header, returns
33   /// 0. Otherwise, returns the priority of the matching category or INT_MAX.
34   /// NOTE: this API is not thread-safe!
35   int getIncludePriority(StringRef IncludeName, bool CheckMainHeader) const;
36   int getSortIncludePriority(StringRef IncludeName, bool CheckMainHeader) const;
37 
38 private:
39   bool isMainHeader(StringRef IncludeName) const;
40 
41   const IncludeStyle Style;
42   bool IsMainFile;
43   std::string FileName;
44   SmallVector<llvm::Regex, 4> CategoryRegexs;
45 };
46 
47 /// Generates replacements for inserting or deleting #include directives in a
48 /// file.
49 class HeaderIncludes {
50 public:
51   HeaderIncludes(llvm::StringRef FileName, llvm::StringRef Code,
52                  const IncludeStyle &Style);
53 
54   /// Inserts an #include directive of \p Header into the code. If \p IsAngled
55   /// is true, \p Header will be quoted with <> in the directive; otherwise, it
56   /// will be quoted with "".
57   ///
58   /// When searching for points to insert new header, this ignores #include's
59   /// after the #include block(s) in the beginning of a file to avoid inserting
60   /// headers into code sections where new #include's should not be added by
61   /// default. These code sections include:
62   ///   - raw string literals (containing #include).
63   ///   - #if blocks.
64   ///   - Special #include's among declarations (e.g. functions).
65   ///
66   /// Returns a replacement that inserts the new header into a suitable #include
67   /// block of the same category. This respects the order of the existing
68   /// #includes in the block; if the existing #includes are not already sorted,
69   /// this will simply insert the #include in front of the first #include of the
70   /// same category in the code that should be sorted after \p IncludeName. If
71   /// \p IncludeName already exists (with exactly the same spelling), this
72   /// returns None.
73   llvm::Optional<tooling::Replacement> insert(llvm::StringRef Header,
74                                               bool IsAngled) const;
75 
76   /// Removes all existing #includes of \p Header quoted with <> if \p IsAngled
77   /// is true or "" if \p IsAngled is false.
78   /// This doesn't resolve the header file path; it only deletes #includes with
79   /// exactly the same spelling.
80   tooling::Replacements remove(llvm::StringRef Header, bool IsAngled) const;
81 
82 private:
83   struct Include {
84     Include(StringRef Name, tooling::Range R) : Name(Name), R(R) {}
85 
86     // An include header quoted with either <> or "".
87     std::string Name;
88     // The range of the whole line of include directive including any leading
89     // whitespaces and trailing comment.
90     tooling::Range R;
91   };
92 
93   void addExistingInclude(Include IncludeToAdd, unsigned NextLineOffset);
94 
95   std::string FileName;
96   std::string Code;
97 
98   // Map from include name (quotation trimmed) to a list of existing includes
99   // (in case there are more than one) with the name in the current file. <x>
100   // and "x" will be treated as the same header when deleting #includes.
101   // std::list is used for pointers stability (see IncludesByPriority)
102   llvm::StringMap<std::list<Include>> ExistingIncludes;
103 
104   /// Map from priorities of #include categories to all #includes in the same
105   /// category. This is used to find #includes of the same category when
106   /// inserting new #includes. #includes in the same categories are sorted in
107   /// in the order they appear in the source file.
108   /// See comment for "FormatStyle::IncludeCategories" for details about include
109   /// priorities.
110   std::unordered_map<int, llvm::SmallVector<const Include *, 8>>
111       IncludesByPriority;
112 
113   int FirstIncludeOffset;
114   // All new headers should be inserted after this offset (e.g. after header
115   // guards, file comment).
116   unsigned MinInsertOffset;
117   // Max insertion offset in the original code. For example, we want to avoid
118   // inserting new #includes into the actual code section (e.g. after a
119   // declaration).
120   unsigned MaxInsertOffset;
121   IncludeCategoryManager Categories;
122   // Record the offset of the end of the last include in each category.
123   std::unordered_map<int, int> CategoryEndOffsets;
124 
125   // All possible priorities.
126   std::set<int> Priorities;
127 
128   // Matches a whole #include directive.
129   llvm::Regex IncludeRegex;
130 };
131 
132 } // namespace tooling
133 } // namespace clang
134 
135 #endif // LLVM_CLANG_TOOLING_INCLUSIONS_HEADERINCLUDES_H
136