summaryrefslogtreecommitdiff
path: root/lib/Format/WhitespaceManager.cpp
blob: 7ffebacba58262478bc5ab9ee26607ee96a2f14e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
//===--- WhitespaceManager.cpp - Format C++ code --------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
///
/// \file
/// \brief This file implements WhitespaceManager class.
///
//===----------------------------------------------------------------------===//

#include "WhitespaceManager.h"
#include "llvm/ADT/STLExtras.h"

namespace clang {
namespace format {

void WhitespaceManager::replaceWhitespace(const AnnotatedToken &Tok,
                                          unsigned NewLines, unsigned Spaces,
                                          unsigned WhitespaceStartColumn) {
  if (NewLines > 0)
    alignEscapedNewlines();

  // 2+ newlines mean an empty line separating logic scopes.
  if (NewLines >= 2)
    alignComments();

  // Align line comments if they are trailing or if they continue other
  // trailing comments.
  if (Tok.isTrailingComment()) {
    SourceLocation TokenEndLoc = Tok.FormatTok.getStartOfNonWhitespace()
        .getLocWithOffset(Tok.FormatTok.TokenLength);
    // Remove the comment's trailing whitespace.
    if (Tok.FormatTok.TrailingWhiteSpaceLength != 0)
      Replaces.insert(tooling::Replacement(
          SourceMgr, TokenEndLoc, Tok.FormatTok.TrailingWhiteSpaceLength, ""));

    bool LineExceedsColumnLimit =
        Spaces + WhitespaceStartColumn + Tok.FormatTok.TokenLength >
        Style.ColumnLimit;
    // Align comment with other comments.
    if ((Tok.Parent != NULL || !Comments.empty()) &&
        !LineExceedsColumnLimit) {
      unsigned MinColumn =
          NewLines > 0 ? Spaces : WhitespaceStartColumn + Spaces;
      unsigned MaxColumn = Style.ColumnLimit - Tok.FormatTok.TokenLength;
      Comments.push_back(StoredToken(
          Tok.FormatTok.WhiteSpaceStart, Tok.FormatTok.WhiteSpaceLength,
          MinColumn, MaxColumn, NewLines, Spaces));
      return;
    }
  }

  // If this line does not have a trailing comment, align the stored comments.
  if (Tok.Children.empty() && !Tok.isTrailingComment())
    alignComments();

  storeReplacement(Tok.FormatTok.WhiteSpaceStart,
                   Tok.FormatTok.WhiteSpaceLength,
                   getNewLineText(NewLines, Spaces));
}

void WhitespaceManager::replacePPWhitespace(const AnnotatedToken &Tok,
                                            unsigned NewLines, unsigned Spaces,
                                            unsigned WhitespaceStartColumn) {
  if (NewLines == 0) {
    replaceWhitespace(Tok, NewLines, Spaces, WhitespaceStartColumn);
  } else {
    // The earliest position for "\" is 2 after the last token.
    unsigned MinColumn = WhitespaceStartColumn + 2;
    unsigned MaxColumn = Style.ColumnLimit;
    EscapedNewlines.push_back(StoredToken(
        Tok.FormatTok.WhiteSpaceStart, Tok.FormatTok.WhiteSpaceLength,
        MinColumn, MaxColumn, NewLines, Spaces));
  }
}

void WhitespaceManager::breakToken(const FormatToken &Tok, unsigned Offset,
                                   unsigned ReplaceChars, StringRef Prefix,
                                   StringRef Postfix, bool InPPDirective,
                                   unsigned Spaces,
                                   unsigned WhitespaceStartColumn) {
  SourceLocation Location =
      Tok.getStartOfNonWhitespace().getLocWithOffset(Offset);
  if (InPPDirective) {
    // The earliest position for "\" is 2 after the last token.
    unsigned MinColumn = WhitespaceStartColumn + 2;
    unsigned MaxColumn = Style.ColumnLimit;
    StoredToken StoredTok = StoredToken(Location, ReplaceChars, MinColumn,
                                        MaxColumn, /*NewLines=*/ 1, Spaces);
    StoredTok.Prefix = Prefix;
    StoredTok.Postfix = Postfix;
    EscapedNewlines.push_back(StoredTok);
  } else {
    std::string ReplacementText =
        (Prefix + getNewLineText(1, Spaces) + Postfix).str();
    Replaces.insert(tooling::Replacement(SourceMgr, Location, ReplaceChars,
                                         ReplacementText));
  }
}

const tooling::Replacements &WhitespaceManager::generateReplacements() {
  alignComments();
  alignEscapedNewlines();
  return Replaces;
}

void WhitespaceManager::addReplacement(const SourceLocation &SourceLoc,
                                       unsigned ReplaceChars, StringRef Text) {
  Replaces.insert(
      tooling::Replacement(SourceMgr, SourceLoc, ReplaceChars, Text));
}

void WhitespaceManager::addUntouchableComment(unsigned Column) {
  StoredToken Tok = StoredToken(SourceLocation(), 0, Column, Column, 0, 0);
  Tok.Untouchable = true;
  Comments.push_back(Tok);
}

std::string WhitespaceManager::getNewLineText(unsigned NewLines,
                                              unsigned Spaces) {
  return std::string(NewLines, '\n') + getIndentText(Spaces);
}

std::string WhitespaceManager::getNewLineText(unsigned NewLines,
                                              unsigned Spaces,
                                              unsigned WhitespaceStartColumn,
                                              unsigned EscapedNewlineColumn) {
  std::string NewLineText;
  if (NewLines > 0) {
    unsigned Offset =
        std::min<int>(EscapedNewlineColumn - 1, WhitespaceStartColumn);
    for (unsigned i = 0; i < NewLines; ++i) {
      NewLineText += std::string(EscapedNewlineColumn - Offset - 1, ' ');
      NewLineText += "\\\n";
      Offset = 0;
    }
  }
  return NewLineText + getIndentText(Spaces);
}

std::string WhitespaceManager::getIndentText(unsigned Spaces) {
  if (!Style.UseTab)
    return std::string(Spaces, ' ');

  return std::string(Spaces / Style.IndentWidth, '\t') +
         std::string(Spaces % Style.IndentWidth, ' ');
}

void WhitespaceManager::alignComments() {
  unsigned MinColumn = 0;
  unsigned MaxColumn = UINT_MAX;
  token_iterator Start = Comments.begin();
  for (token_iterator I = Start, E = Comments.end(); I != E; ++I) {
    if (I->MinColumn > MaxColumn || I->MaxColumn < MinColumn) {
      alignComments(Start, I, MinColumn);
      MinColumn = I->MinColumn;
      MaxColumn = I->MaxColumn;
      Start = I;
    } else {
      MinColumn = std::max(MinColumn, I->MinColumn);
      MaxColumn = std::min(MaxColumn, I->MaxColumn);
    }
  }
  alignComments(Start, Comments.end(), MinColumn);
  Comments.clear();
}

void WhitespaceManager::alignComments(token_iterator I, token_iterator E,
                                      unsigned Column) {
  while (I != E) {
    if (!I->Untouchable) {
      unsigned Spaces = I->Spaces + Column - I->MinColumn;
      storeReplacement(I->ReplacementLoc, I->ReplacementLength,
                       getNewLineText(I->NewLines, Spaces));
    }
    ++I;
  }
}

void WhitespaceManager::alignEscapedNewlines() {
  unsigned MinColumn;
  if (Style.AlignEscapedNewlinesLeft) {
    MinColumn = 0;
    for (token_iterator I = EscapedNewlines.begin(), E = EscapedNewlines.end();
         I != E; ++I) {
      if (I->MinColumn > MinColumn)
        MinColumn = I->MinColumn;
    }
  } else {
    MinColumn = Style.ColumnLimit;
  }

  for (token_iterator I = EscapedNewlines.begin(), E = EscapedNewlines.end();
       I != E; ++I) {
    // I->MinColumn - 2 is the end of the previous token (i.e. the
    // WhitespaceStartColumn).
    storeReplacement(
        I->ReplacementLoc, I->ReplacementLength,
        I->Prefix + getNewLineText(I->NewLines, I->Spaces, I->MinColumn - 2,
                                   MinColumn) + I->Postfix);

  }
  EscapedNewlines.clear();
}

void WhitespaceManager::storeReplacement(SourceLocation Loc, unsigned Length,
                                         const std::string Text) {
  // Don't create a replacement, if it does not change anything.
  if (StringRef(SourceMgr.getCharacterData(Loc), Length) == Text)
    return;
  Replaces.insert(tooling::Replacement(SourceMgr, Loc, Length, Text));
}

} // namespace format
} // namespace clang