1 //===--- Rewriter.h - Code rewriting interface ------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 //  This file defines the Rewriter class, which is used for code
11 //  transformations.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_CLANG_REWRITE_CORE_REWRITER_H
16 #define LLVM_CLANG_REWRITE_CORE_REWRITER_H
17 
18 #include "clang/Basic/SourceLocation.h"
19 #include "clang/Rewrite/Core/RewriteBuffer.h"
20 #include <cstring>
21 #include <map>
22 #include <string>
23 
24 namespace clang {
25   class LangOptions;
26   class SourceManager;
27 
28 /// Rewriter - This is the main interface to the rewrite buffers.  Its primary
29 /// job is to dispatch high-level requests to the low-level RewriteBuffers that
30 /// are involved.
31 class Rewriter {
32   SourceManager *SourceMgr;
33   const LangOptions *LangOpts;
34   std::map<FileID, RewriteBuffer> RewriteBuffers;
35 public:
36   struct RewriteOptions {
37     /// \brief Given a source range, true to include previous inserts at the
38     /// beginning of the range as part of the range itself (true by default).
39     bool IncludeInsertsAtBeginOfRange;
40     /// \brief Given a source range, true to include previous inserts at the
41     /// end of the range as part of the range itself (true by default).
42     bool IncludeInsertsAtEndOfRange;
43     /// \brief If true and removing some text leaves a blank line
44     /// also remove the empty line (false by default).
45     bool RemoveLineIfEmpty;
46 
RewriteOptionsRewriteOptions47     RewriteOptions()
48       : IncludeInsertsAtBeginOfRange(true),
49         IncludeInsertsAtEndOfRange(true),
50         RemoveLineIfEmpty(false) { }
51   };
52 
53   typedef std::map<FileID, RewriteBuffer>::iterator buffer_iterator;
54   typedef std::map<FileID, RewriteBuffer>::const_iterator const_buffer_iterator;
55 
Rewriter(SourceManager & SM,const LangOptions & LO)56   explicit Rewriter(SourceManager &SM, const LangOptions &LO)
57     : SourceMgr(&SM), LangOpts(&LO) {}
Rewriter()58   explicit Rewriter() : SourceMgr(nullptr), LangOpts(nullptr) {}
59 
setSourceMgr(SourceManager & SM,const LangOptions & LO)60   void setSourceMgr(SourceManager &SM, const LangOptions &LO) {
61     SourceMgr = &SM;
62     LangOpts = &LO;
63   }
getSourceMgr()64   SourceManager &getSourceMgr() const { return *SourceMgr; }
getLangOpts()65   const LangOptions &getLangOpts() const { return *LangOpts; }
66 
67   /// isRewritable - Return true if this location is a raw file location, which
68   /// is rewritable.  Locations from macros, etc are not rewritable.
isRewritable(SourceLocation Loc)69   static bool isRewritable(SourceLocation Loc) {
70     return Loc.isFileID();
71   }
72 
73   /// getRangeSize - Return the size in bytes of the specified range if they
74   /// are in the same file.  If not, this returns -1.
75   int getRangeSize(SourceRange Range,
76                    RewriteOptions opts = RewriteOptions()) const;
77   int getRangeSize(const CharSourceRange &Range,
78                    RewriteOptions opts = RewriteOptions()) const;
79 
80   /// getRewrittenText - Return the rewritten form of the text in the specified
81   /// range.  If the start or end of the range was unrewritable or if they are
82   /// in different buffers, this returns an empty string.
83   ///
84   /// Note that this method is not particularly efficient.
85   ///
86   std::string getRewrittenText(SourceRange Range) const;
87 
88   /// InsertText - Insert the specified string at the specified location in the
89   /// original buffer.  This method returns true (and does nothing) if the input
90   /// location was not rewritable, false otherwise.
91   ///
92   /// \param indentNewLines if true new lines in the string are indented
93   /// using the indentation of the source line in position \p Loc.
94   bool InsertText(SourceLocation Loc, StringRef Str,
95                   bool InsertAfter = true, bool indentNewLines = false);
96 
97   /// InsertTextAfter - Insert the specified string at the specified location in
98   ///  the original buffer.  This method returns true (and does nothing) if
99   ///  the input location was not rewritable, false otherwise.  Text is
100   ///  inserted after any other text that has been previously inserted
101   ///  at the some point (the default behavior for InsertText).
InsertTextAfter(SourceLocation Loc,StringRef Str)102   bool InsertTextAfter(SourceLocation Loc, StringRef Str) {
103     return InsertText(Loc, Str);
104   }
105 
106   /// \brief Insert the specified string after the token in the
107   /// specified location.
108   bool InsertTextAfterToken(SourceLocation Loc, StringRef Str);
109 
110   /// InsertText - Insert the specified string at the specified location in the
111   /// original buffer.  This method returns true (and does nothing) if the input
112   /// location was not rewritable, false otherwise.  Text is
113   /// inserted before any other text that has been previously inserted
114   /// at the some point.
InsertTextBefore(SourceLocation Loc,StringRef Str)115   bool InsertTextBefore(SourceLocation Loc, StringRef Str) {
116     return InsertText(Loc, Str, false);
117   }
118 
119   /// RemoveText - Remove the specified text region.
120   bool RemoveText(SourceLocation Start, unsigned Length,
121                   RewriteOptions opts = RewriteOptions());
122 
123   /// \brief Remove the specified text region.
124   bool RemoveText(CharSourceRange range,
125                   RewriteOptions opts = RewriteOptions()) {
126     return RemoveText(range.getBegin(), getRangeSize(range, opts), opts);
127   }
128 
129   /// \brief Remove the specified text region.
130   bool RemoveText(SourceRange range, RewriteOptions opts = RewriteOptions()) {
131     return RemoveText(range.getBegin(), getRangeSize(range, opts), opts);
132   }
133 
134   /// ReplaceText - This method replaces a range of characters in the input
135   /// buffer with a new string.  This is effectively a combined "remove/insert"
136   /// operation.
137   bool ReplaceText(SourceLocation Start, unsigned OrigLength,
138                    StringRef NewStr);
139 
140   /// ReplaceText - This method replaces a range of characters in the input
141   /// buffer with a new string.  This is effectively a combined "remove/insert"
142   /// operation.
ReplaceText(SourceRange range,StringRef NewStr)143   bool ReplaceText(SourceRange range, StringRef NewStr) {
144     return ReplaceText(range.getBegin(), getRangeSize(range), NewStr);
145   }
146 
147   /// ReplaceText - This method replaces a range of characters in the input
148   /// buffer with a new string.  This is effectively a combined "remove/insert"
149   /// operation.
150   bool ReplaceText(SourceRange range, SourceRange replacementRange);
151 
152   /// \brief Increase indentation for the lines between the given source range.
153   /// To determine what the indentation should be, 'parentIndent' is used
154   /// that should be at a source location with an indentation one degree
155   /// lower than the given range.
156   bool IncreaseIndentation(CharSourceRange range, SourceLocation parentIndent);
IncreaseIndentation(SourceRange range,SourceLocation parentIndent)157   bool IncreaseIndentation(SourceRange range, SourceLocation parentIndent) {
158     return IncreaseIndentation(CharSourceRange::getTokenRange(range),
159                                parentIndent);
160   }
161 
162   /// getEditBuffer - This is like getRewriteBufferFor, but always returns a
163   /// buffer, and allows you to write on it directly.  This is useful if you
164   /// want efficient low-level access to apis for scribbling on one specific
165   /// FileID's buffer.
166   RewriteBuffer &getEditBuffer(FileID FID);
167 
168   /// getRewriteBufferFor - Return the rewrite buffer for the specified FileID.
169   /// If no modification has been made to it, return null.
getRewriteBufferFor(FileID FID)170   const RewriteBuffer *getRewriteBufferFor(FileID FID) const {
171     std::map<FileID, RewriteBuffer>::const_iterator I =
172       RewriteBuffers.find(FID);
173     return I == RewriteBuffers.end() ? nullptr : &I->second;
174   }
175 
176   // Iterators over rewrite buffers.
buffer_begin()177   buffer_iterator buffer_begin() { return RewriteBuffers.begin(); }
buffer_end()178   buffer_iterator buffer_end() { return RewriteBuffers.end(); }
buffer_begin()179   const_buffer_iterator buffer_begin() const { return RewriteBuffers.begin(); }
buffer_end()180   const_buffer_iterator buffer_end() const { return RewriteBuffers.end(); }
181 
182   /// overwriteChangedFiles - Save all changed files to disk.
183   ///
184   /// Returns true if any files were not saved successfully.
185   /// Outputs diagnostics via the source manager's diagnostic engine
186   /// in case of an error.
187   bool overwriteChangedFiles();
188 
189 private:
190   unsigned getLocationOffsetAndFileID(SourceLocation Loc, FileID &FID) const;
191 };
192 
193 } // end namespace clang
194 
195 #endif
196