clang  7.0.0
BreakableToken.cpp
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1 //===--- BreakableToken.cpp - Format C++ code -----------------------------===//
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 /// \file
11 /// Contains implementation of BreakableToken class and classes derived
12 /// from it.
13 ///
14 //===----------------------------------------------------------------------===//
15 
16 #include "BreakableToken.h"
17 #include "ContinuationIndenter.h"
18 #include "clang/Basic/CharInfo.h"
19 #include "clang/Format/Format.h"
20 #include "llvm/ADT/STLExtras.h"
21 #include "llvm/Support/Debug.h"
22 #include <algorithm>
23 
24 #define DEBUG_TYPE "format-token-breaker"
25 
26 namespace clang {
27 namespace format {
28 
29 static const char *const Blanks = " \t\v\f\r";
30 static bool IsBlank(char C) {
31  switch (C) {
32  case ' ':
33  case '\t':
34  case '\v':
35  case '\f':
36  case '\r':
37  return true;
38  default:
39  return false;
40  }
41 }
42 
43 static StringRef getLineCommentIndentPrefix(StringRef Comment,
44  const FormatStyle &Style) {
45  static const char *const KnownCStylePrefixes[] = {"///<", "//!<", "///", "//",
46  "//!"};
47  static const char *const KnownTextProtoPrefixes[] = {"//", "#", "##", "###",
48  "####"};
49  ArrayRef<const char *> KnownPrefixes(KnownCStylePrefixes);
51  KnownPrefixes = KnownTextProtoPrefixes;
52 
53  StringRef LongestPrefix;
54  for (StringRef KnownPrefix : KnownPrefixes) {
55  if (Comment.startswith(KnownPrefix)) {
56  size_t PrefixLength = KnownPrefix.size();
57  while (PrefixLength < Comment.size() && Comment[PrefixLength] == ' ')
58  ++PrefixLength;
59  if (PrefixLength > LongestPrefix.size())
60  LongestPrefix = Comment.substr(0, PrefixLength);
61  }
62  }
63  return LongestPrefix;
64 }
65 
66 static BreakableToken::Split getCommentSplit(StringRef Text,
67  unsigned ContentStartColumn,
68  unsigned ColumnLimit,
69  unsigned TabWidth,
71  LLVM_DEBUG(llvm::dbgs() << "Comment split: \"" << Text << ", " << ColumnLimit
72  << "\", Content start: " << ContentStartColumn
73  << "\n");
74  if (ColumnLimit <= ContentStartColumn + 1)
75  return BreakableToken::Split(StringRef::npos, 0);
76 
77  unsigned MaxSplit = ColumnLimit - ContentStartColumn + 1;
78  unsigned MaxSplitBytes = 0;
79 
80  for (unsigned NumChars = 0;
81  NumChars < MaxSplit && MaxSplitBytes < Text.size();) {
82  unsigned BytesInChar =
83  encoding::getCodePointNumBytes(Text[MaxSplitBytes], Encoding);
84  NumChars +=
85  encoding::columnWidthWithTabs(Text.substr(MaxSplitBytes, BytesInChar),
86  ContentStartColumn, TabWidth, Encoding);
87  MaxSplitBytes += BytesInChar;
88  }
89 
90  StringRef::size_type SpaceOffset = Text.find_last_of(Blanks, MaxSplitBytes);
91 
92  // Do not split before a number followed by a dot: this would be interpreted
93  // as a numbered list, which would prevent re-flowing in subsequent passes.
94  static auto *const kNumberedListRegexp = new llvm::Regex("^[1-9][0-9]?\\.");
95  if (SpaceOffset != StringRef::npos &&
96  kNumberedListRegexp->match(Text.substr(SpaceOffset).ltrim(Blanks)))
97  SpaceOffset = Text.find_last_of(Blanks, SpaceOffset);
98 
99  if (SpaceOffset == StringRef::npos ||
100  // Don't break at leading whitespace.
101  Text.find_last_not_of(Blanks, SpaceOffset) == StringRef::npos) {
102  // Make sure that we don't break at leading whitespace that
103  // reaches past MaxSplit.
104  StringRef::size_type FirstNonWhitespace = Text.find_first_not_of(Blanks);
105  if (FirstNonWhitespace == StringRef::npos)
106  // If the comment is only whitespace, we cannot split.
107  return BreakableToken::Split(StringRef::npos, 0);
108  SpaceOffset = Text.find_first_of(
109  Blanks, std::max<unsigned>(MaxSplitBytes, FirstNonWhitespace));
110  }
111  if (SpaceOffset != StringRef::npos && SpaceOffset != 0) {
112  StringRef BeforeCut = Text.substr(0, SpaceOffset).rtrim(Blanks);
113  StringRef AfterCut = Text.substr(SpaceOffset).ltrim(Blanks);
114  return BreakableToken::Split(BeforeCut.size(),
115  AfterCut.begin() - BeforeCut.end());
116  }
117  return BreakableToken::Split(StringRef::npos, 0);
118 }
119 
120 static BreakableToken::Split
121 getStringSplit(StringRef Text, unsigned UsedColumns, unsigned ColumnLimit,
122  unsigned TabWidth, encoding::Encoding Encoding) {
123  // FIXME: Reduce unit test case.
124  if (Text.empty())
125  return BreakableToken::Split(StringRef::npos, 0);
126  if (ColumnLimit <= UsedColumns)
127  return BreakableToken::Split(StringRef::npos, 0);
128  unsigned MaxSplit = ColumnLimit - UsedColumns;
129  StringRef::size_type SpaceOffset = 0;
130  StringRef::size_type SlashOffset = 0;
131  StringRef::size_type WordStartOffset = 0;
132  StringRef::size_type SplitPoint = 0;
133  for (unsigned Chars = 0;;) {
134  unsigned Advance;
135  if (Text[0] == '\\') {
136  Advance = encoding::getEscapeSequenceLength(Text);
137  Chars += Advance;
138  } else {
139  Advance = encoding::getCodePointNumBytes(Text[0], Encoding);
141  Text.substr(0, Advance), UsedColumns + Chars, TabWidth, Encoding);
142  }
143 
144  if (Chars > MaxSplit || Text.size() <= Advance)
145  break;
146 
147  if (IsBlank(Text[0]))
148  SpaceOffset = SplitPoint;
149  if (Text[0] == '/')
150  SlashOffset = SplitPoint;
151  if (Advance == 1 && !isAlphanumeric(Text[0]))
152  WordStartOffset = SplitPoint;
153 
154  SplitPoint += Advance;
155  Text = Text.substr(Advance);
156  }
157 
158  if (SpaceOffset != 0)
159  return BreakableToken::Split(SpaceOffset + 1, 0);
160  if (SlashOffset != 0)
161  return BreakableToken::Split(SlashOffset + 1, 0);
162  if (WordStartOffset != 0)
163  return BreakableToken::Split(WordStartOffset + 1, 0);
164  if (SplitPoint != 0)
165  return BreakableToken::Split(SplitPoint, 0);
166  return BreakableToken::Split(StringRef::npos, 0);
167 }
168 
170  assert((Token.is(TT_BlockComment) || Token.is(TT_LineComment)) &&
171  "formatting regions are switched by comment tokens");
172  StringRef Content = Token.TokenText.substr(2).ltrim();
173  return Content.startswith("clang-format on") ||
174  Content.startswith("clang-format off");
175 }
176 
177 unsigned
178 BreakableToken::getLengthAfterCompression(unsigned RemainingTokenColumns,
179  Split Split) const {
180  // Example: consider the content
181  // lala lala
182  // - RemainingTokenColumns is the original number of columns, 10;
183  // - Split is (4, 2), denoting the two spaces between the two words;
184  //
185  // We compute the number of columns when the split is compressed into a single
186  // space, like:
187  // lala lala
188  //
189  // FIXME: Correctly measure the length of whitespace in Split.second so it
190  // works with tabs.
191  return RemainingTokenColumns + 1 - Split.second;
192 }
193 
194 unsigned BreakableStringLiteral::getLineCount() const { return 1; }
195 
196 unsigned BreakableStringLiteral::getRangeLength(unsigned LineIndex,
197  unsigned Offset,
198  StringRef::size_type Length,
199  unsigned StartColumn) const {
200  llvm_unreachable("Getting the length of a part of the string literal "
201  "indicates that the code tries to reflow it.");
202 }
203 
204 unsigned
206  unsigned StartColumn) const {
207  return UnbreakableTailLength + Postfix.size() +
208  encoding::columnWidthWithTabs(Line.substr(Offset, StringRef::npos),
210 }
211 
213  bool Break) const {
214  return StartColumn + Prefix.size();
215 }
216 
218  const FormatToken &Tok, unsigned StartColumn, StringRef Prefix,
219  StringRef Postfix, unsigned UnbreakableTailLength, bool InPPDirective,
221  : BreakableToken(Tok, InPPDirective, Encoding, Style),
222  StartColumn(StartColumn), Prefix(Prefix), Postfix(Postfix),
223  UnbreakableTailLength(UnbreakableTailLength) {
224  assert(Tok.TokenText.startswith(Prefix) && Tok.TokenText.endswith(Postfix));
225  Line = Tok.TokenText.substr(
226  Prefix.size(), Tok.TokenText.size() - Prefix.size() - Postfix.size());
227 }
228 
229 BreakableToken::Split BreakableStringLiteral::getSplit(
230  unsigned LineIndex, unsigned TailOffset, unsigned ColumnLimit,
231  unsigned ContentStartColumn, llvm::Regex &CommentPragmasRegex) const {
232  return getStringSplit(Line.substr(TailOffset), ContentStartColumn,
233  ColumnLimit - Postfix.size(), Style.TabWidth, Encoding);
234 }
235 
236 void BreakableStringLiteral::insertBreak(unsigned LineIndex,
237  unsigned TailOffset, Split Split,
238  unsigned ContentIndent,
239  WhitespaceManager &Whitespaces) const {
240  Whitespaces.replaceWhitespaceInToken(
241  Tok, Prefix.size() + TailOffset + Split.first, Split.second, Postfix,
243 }
244 
246  unsigned StartColumn, bool InPPDirective,
248  const FormatStyle &Style)
249  : BreakableToken(Token, InPPDirective, Encoding, Style),
250  StartColumn(StartColumn) {}
251 
252 unsigned BreakableComment::getLineCount() const { return Lines.size(); }
253 
254 BreakableToken::Split
255 BreakableComment::getSplit(unsigned LineIndex, unsigned TailOffset,
256  unsigned ColumnLimit, unsigned ContentStartColumn,
257  llvm::Regex &CommentPragmasRegex) const {
258  // Don't break lines matching the comment pragmas regex.
259  if (CommentPragmasRegex.match(Content[LineIndex]))
260  return Split(StringRef::npos, 0);
261  return getCommentSplit(Content[LineIndex].substr(TailOffset),
262  ContentStartColumn, ColumnLimit, Style.TabWidth,
263  Encoding);
264 }
265 
267  unsigned LineIndex, unsigned TailOffset, Split Split,
268  WhitespaceManager &Whitespaces) const {
269  StringRef Text = Content[LineIndex].substr(TailOffset);
270  // Text is relative to the content line, but Whitespaces operates relative to
271  // the start of the corresponding token, so compute the start of the Split
272  // that needs to be compressed into a single space relative to the start of
273  // its token.
274  unsigned BreakOffsetInToken =
275  Text.data() - tokenAt(LineIndex).TokenText.data() + Split.first;
276  unsigned CharsToRemove = Split.second;
277  Whitespaces.replaceWhitespaceInToken(
278  tokenAt(LineIndex), BreakOffsetInToken, CharsToRemove, "", "",
279  /*InPPDirective=*/false, /*Newlines=*/0, /*Spaces=*/1);
280 }
281 
282 const FormatToken &BreakableComment::tokenAt(unsigned LineIndex) const {
283  return Tokens[LineIndex] ? *Tokens[LineIndex] : Tok;
284 }
285 
286 static bool mayReflowContent(StringRef Content) {
287  Content = Content.trim(Blanks);
288  // Lines starting with '@' commonly have special meaning.
289  // Lines starting with '-', '-#', '+' or '*' are bulleted/numbered lists.
290  bool hasSpecialMeaningPrefix = false;
291  for (StringRef Prefix :
292  {"@", "TODO", "FIXME", "XXX", "-# ", "- ", "+ ", "* "}) {
293  if (Content.startswith(Prefix)) {
294  hasSpecialMeaningPrefix = true;
295  break;
296  }
297  }
298 
299  // Numbered lists may also start with a number followed by '.'
300  // To avoid issues if a line starts with a number which is actually the end
301  // of a previous line, we only consider numbers with up to 2 digits.
302  static auto *const kNumberedListRegexp = new llvm::Regex("^[1-9][0-9]?\\. ");
303  hasSpecialMeaningPrefix =
304  hasSpecialMeaningPrefix || kNumberedListRegexp->match(Content);
305 
306  // Simple heuristic for what to reflow: content should contain at least two
307  // characters and either the first or second character must be
308  // non-punctuation.
309  return Content.size() >= 2 && !hasSpecialMeaningPrefix &&
310  !Content.endswith("\\") &&
311  // Note that this is UTF-8 safe, since if isPunctuation(Content[0]) is
312  // true, then the first code point must be 1 byte long.
313  (!isPunctuation(Content[0]) || !isPunctuation(Content[1]));
314 }
315 
317  const FormatToken &Token, unsigned StartColumn,
318  unsigned OriginalStartColumn, bool FirstInLine, bool InPPDirective,
320  : BreakableComment(Token, StartColumn, InPPDirective, Encoding, Style),
321  DelimitersOnNewline(false),
322  UnbreakableTailLength(Token.UnbreakableTailLength) {
323  assert(Tok.is(TT_BlockComment) &&
324  "block comment section must start with a block comment");
325 
326  StringRef TokenText(Tok.TokenText);
327  assert(TokenText.startswith("/*") && TokenText.endswith("*/"));
328  TokenText.substr(2, TokenText.size() - 4).split(Lines, "\n");
329 
330  int IndentDelta = StartColumn - OriginalStartColumn;
331  Content.resize(Lines.size());
332  Content[0] = Lines[0];
333  ContentColumn.resize(Lines.size());
334  // Account for the initial '/*'.
335  ContentColumn[0] = StartColumn + 2;
336  Tokens.resize(Lines.size());
337  for (size_t i = 1; i < Lines.size(); ++i)
338  adjustWhitespace(i, IndentDelta);
339 
340  // Align decorations with the column of the star on the first line,
341  // that is one column after the start "/*".
342  DecorationColumn = StartColumn + 1;
343 
344  // Account for comment decoration patterns like this:
345  //
346  // /*
347  // ** blah blah blah
348  // */
349  if (Lines.size() >= 2 && Content[1].startswith("**") &&
350  static_cast<unsigned>(ContentColumn[1]) == StartColumn) {
351  DecorationColumn = StartColumn;
352  }
353 
354  Decoration = "* ";
355  if (Lines.size() == 1 && !FirstInLine) {
356  // Comments for which FirstInLine is false can start on arbitrary column,
357  // and available horizontal space can be too small to align consecutive
358  // lines with the first one.
359  // FIXME: We could, probably, align them to current indentation level, but
360  // now we just wrap them without stars.
361  Decoration = "";
362  }
363  for (size_t i = 1, e = Lines.size(); i < e && !Decoration.empty(); ++i) {
364  // If the last line is empty, the closing "*/" will have a star.
365  if (i + 1 == e && Content[i].empty())
366  break;
367  if (!Content[i].empty() && i + 1 != e && Decoration.startswith(Content[i]))
368  continue;
369  while (!Content[i].startswith(Decoration))
370  Decoration = Decoration.substr(0, Decoration.size() - 1);
371  }
372 
373  LastLineNeedsDecoration = true;
374  IndentAtLineBreak = ContentColumn[0] + 1;
375  for (size_t i = 1, e = Lines.size(); i < e; ++i) {
376  if (Content[i].empty()) {
377  if (i + 1 == e) {
378  // Empty last line means that we already have a star as a part of the
379  // trailing */. We also need to preserve whitespace, so that */ is
380  // correctly indented.
381  LastLineNeedsDecoration = false;
382  // Align the star in the last '*/' with the stars on the previous lines.
383  if (e >= 2 && !Decoration.empty()) {
384  ContentColumn[i] = DecorationColumn;
385  }
386  } else if (Decoration.empty()) {
387  // For all other lines, set the start column to 0 if they're empty, so
388  // we do not insert trailing whitespace anywhere.
389  ContentColumn[i] = 0;
390  }
391  continue;
392  }
393 
394  // The first line already excludes the star.
395  // The last line excludes the star if LastLineNeedsDecoration is false.
396  // For all other lines, adjust the line to exclude the star and
397  // (optionally) the first whitespace.
398  unsigned DecorationSize = Decoration.startswith(Content[i])
399  ? Content[i].size()
400  : Decoration.size();
401  if (DecorationSize) {
402  ContentColumn[i] = DecorationColumn + DecorationSize;
403  }
404  Content[i] = Content[i].substr(DecorationSize);
405  if (!Decoration.startswith(Content[i]))
406  IndentAtLineBreak =
407  std::min<int>(IndentAtLineBreak, std::max(0, ContentColumn[i]));
408  }
409  IndentAtLineBreak = std::max<unsigned>(IndentAtLineBreak, Decoration.size());
410 
411  // Detect a multiline jsdoc comment and set DelimitersOnNewline in that case.
412  if (Style.Language == FormatStyle::LK_JavaScript ||
413  Style.Language == FormatStyle::LK_Java) {
414  if ((Lines[0] == "*" || Lines[0].startswith("* ")) && Lines.size() > 1) {
415  // This is a multiline jsdoc comment.
416  DelimitersOnNewline = true;
417  } else if (Lines[0].startswith("* ") && Lines.size() == 1) {
418  // Detect a long single-line comment, like:
419  // /** long long long */
420  // Below, '2' is the width of '*/'.
421  unsigned EndColumn =
422  ContentColumn[0] +
424  Style.TabWidth, Encoding) +
425  2;
426  DelimitersOnNewline = EndColumn > Style.ColumnLimit;
427  }
428  }
429 
430  LLVM_DEBUG({
431  llvm::dbgs() << "IndentAtLineBreak " << IndentAtLineBreak << "\n";
432  llvm::dbgs() << "DelimitersOnNewline " << DelimitersOnNewline << "\n";
433  for (size_t i = 0; i < Lines.size(); ++i) {
434  llvm::dbgs() << i << " |" << Content[i] << "| "
435  << "CC=" << ContentColumn[i] << "| "
436  << "IN=" << (Content[i].data() - Lines[i].data()) << "\n";
437  }
438  });
439 }
440 
441 void BreakableBlockComment::adjustWhitespace(unsigned LineIndex,
442  int IndentDelta) {
443  // When in a preprocessor directive, the trailing backslash in a block comment
444  // is not needed, but can serve a purpose of uniformity with necessary escaped
445  // newlines outside the comment. In this case we remove it here before
446  // trimming the trailing whitespace. The backslash will be re-added later when
447  // inserting a line break.
448  size_t EndOfPreviousLine = Lines[LineIndex - 1].size();
449  if (InPPDirective && Lines[LineIndex - 1].endswith("\\"))
450  --EndOfPreviousLine;
451 
452  // Calculate the end of the non-whitespace text in the previous line.
453  EndOfPreviousLine =
454  Lines[LineIndex - 1].find_last_not_of(Blanks, EndOfPreviousLine);
455  if (EndOfPreviousLine == StringRef::npos)
456  EndOfPreviousLine = 0;
457  else
458  ++EndOfPreviousLine;
459  // Calculate the start of the non-whitespace text in the current line.
460  size_t StartOfLine = Lines[LineIndex].find_first_not_of(Blanks);
461  if (StartOfLine == StringRef::npos)
462  StartOfLine = Lines[LineIndex].rtrim("\r\n").size();
463 
464  StringRef Whitespace = Lines[LineIndex].substr(0, StartOfLine);
465  // Adjust Lines to only contain relevant text.
466  size_t PreviousContentOffset =
467  Content[LineIndex - 1].data() - Lines[LineIndex - 1].data();
468  Content[LineIndex - 1] = Lines[LineIndex - 1].substr(
469  PreviousContentOffset, EndOfPreviousLine - PreviousContentOffset);
470  Content[LineIndex] = Lines[LineIndex].substr(StartOfLine);
471 
472  // Adjust the start column uniformly across all lines.
473  ContentColumn[LineIndex] =
475  IndentDelta;
476 }
477 
478 unsigned BreakableBlockComment::getRangeLength(unsigned LineIndex,
479  unsigned Offset,
480  StringRef::size_type Length,
481  unsigned StartColumn) const {
482  unsigned LineLength =
483  encoding::columnWidthWithTabs(Content[LineIndex].substr(Offset, Length),
484  StartColumn, Style.TabWidth, Encoding);
485  // FIXME: This should go into getRemainingLength instead, but we currently
486  // break tests when putting it there. Investigate how to fix those tests.
487  // The last line gets a "*/" postfix.
488  if (LineIndex + 1 == Lines.size()) {
489  LineLength += 2;
490  // We never need a decoration when breaking just the trailing "*/" postfix.
491  // Note that checking that Length == 0 is not enough, since Length could
492  // also be StringRef::npos.
493  if (Content[LineIndex].substr(Offset, StringRef::npos).empty()) {
494  LineLength -= Decoration.size();
495  }
496  }
497  return LineLength;
498 }
499 
500 unsigned BreakableBlockComment::getRemainingLength(unsigned LineIndex,
501  unsigned Offset,
502  unsigned StartColumn) const {
503  return UnbreakableTailLength +
504  getRangeLength(LineIndex, Offset, StringRef::npos, StartColumn);
505 }
506 
508  bool Break) const {
509  if (Break)
510  return IndentAtLineBreak;
511  return std::max(0, ContentColumn[LineIndex]);
512 }
513 
514 const llvm::StringSet<>
516  "@param", "@return", "@returns", "@throws", "@type", "@template",
517  "@see", "@deprecated", "@define", "@exports", "@mods", "@private",
518 };
519 
520 unsigned BreakableBlockComment::getContentIndent(unsigned LineIndex) const {
523  return 0;
524  // The content at LineIndex 0 of a comment like:
525  // /** line 0 */
526  // is "* line 0", so we need to skip over the decoration in that case.
527  StringRef ContentWithNoDecoration = Content[LineIndex];
528  if (LineIndex == 0 && ContentWithNoDecoration.startswith("*")) {
529  ContentWithNoDecoration = ContentWithNoDecoration.substr(1).ltrim(Blanks);
530  }
531  StringRef FirstWord = ContentWithNoDecoration.substr(
532  0, ContentWithNoDecoration.find_first_of(Blanks));
533  if (ContentIndentingJavadocAnnotations.find(FirstWord) !=
536  return 0;
537 }
538 
539 void BreakableBlockComment::insertBreak(unsigned LineIndex, unsigned TailOffset,
540  Split Split, unsigned ContentIndent,
541  WhitespaceManager &Whitespaces) const {
542  StringRef Text = Content[LineIndex].substr(TailOffset);
543  StringRef Prefix = Decoration;
544  // We need this to account for the case when we have a decoration "* " for all
545  // the lines except for the last one, where the star in "*/" acts as a
546  // decoration.
547  unsigned LocalIndentAtLineBreak = IndentAtLineBreak;
548  if (LineIndex + 1 == Lines.size() &&
549  Text.size() == Split.first + Split.second) {
550  // For the last line we need to break before "*/", but not to add "* ".
551  Prefix = "";
552  if (LocalIndentAtLineBreak >= 2)
553  LocalIndentAtLineBreak -= 2;
554  }
555  // The split offset is from the beginning of the line. Convert it to an offset
556  // from the beginning of the token text.
557  unsigned BreakOffsetInToken =
558  Text.data() - tokenAt(LineIndex).TokenText.data() + Split.first;
559  unsigned CharsToRemove = Split.second;
560  assert(LocalIndentAtLineBreak >= Prefix.size());
561  std::string PrefixWithTrailingIndent = Prefix;
562  for (unsigned I = 0; I < ContentIndent; ++I)
563  PrefixWithTrailingIndent += " ";
564  Whitespaces.replaceWhitespaceInToken(
565  tokenAt(LineIndex), BreakOffsetInToken, CharsToRemove, "",
566  PrefixWithTrailingIndent, InPPDirective, /*Newlines=*/1,
567  /*Spaces=*/LocalIndentAtLineBreak + ContentIndent -
568  PrefixWithTrailingIndent.size());
569 }
570 
571 BreakableToken::Split
573  llvm::Regex &CommentPragmasRegex) const {
574  if (!mayReflow(LineIndex, CommentPragmasRegex))
575  return Split(StringRef::npos, 0);
576 
577  // If we're reflowing into a line with content indent, only reflow the next
578  // line if its starting whitespace matches the content indent.
579  size_t Trimmed = Content[LineIndex].find_first_not_of(Blanks);
580  if (LineIndex) {
581  unsigned PreviousContentIndent = getContentIndent(LineIndex - 1);
582  if (PreviousContentIndent && Trimmed != StringRef::npos &&
583  Trimmed != PreviousContentIndent)
584  return Split(StringRef::npos, 0);
585  }
586 
587  return Split(0, Trimmed != StringRef::npos ? Trimmed : 0);
588 }
589 
591  // A break is introduced when we want delimiters on newline.
592  return DelimitersOnNewline &&
593  Lines[0].substr(1).find_first_not_of(Blanks) != StringRef::npos;
594 }
595 
596 void BreakableBlockComment::reflow(unsigned LineIndex,
597  WhitespaceManager &Whitespaces) const {
598  StringRef TrimmedContent = Content[LineIndex].ltrim(Blanks);
599  // Here we need to reflow.
600  assert(Tokens[LineIndex - 1] == Tokens[LineIndex] &&
601  "Reflowing whitespace within a token");
602  // This is the offset of the end of the last line relative to the start of
603  // the token text in the token.
604  unsigned WhitespaceOffsetInToken = Content[LineIndex - 1].data() +
605  Content[LineIndex - 1].size() -
606  tokenAt(LineIndex).TokenText.data();
607  unsigned WhitespaceLength = TrimmedContent.data() -
608  tokenAt(LineIndex).TokenText.data() -
609  WhitespaceOffsetInToken;
610  Whitespaces.replaceWhitespaceInToken(
611  tokenAt(LineIndex), WhitespaceOffsetInToken,
612  /*ReplaceChars=*/WhitespaceLength, /*PreviousPostfix=*/"",
613  /*CurrentPrefix=*/ReflowPrefix, InPPDirective, /*Newlines=*/0,
614  /*Spaces=*/0);
615 }
616 
618  unsigned LineIndex, WhitespaceManager &Whitespaces) const {
619  if (LineIndex == 0) {
620  if (DelimitersOnNewline) {
621  // Since we're breaking at index 1 below, the break position and the
622  // break length are the same.
623  size_t BreakLength = Lines[0].substr(1).find_first_not_of(Blanks);
624  if (BreakLength != StringRef::npos)
625  insertBreak(LineIndex, 0, Split(1, BreakLength), /*ContentIndent=*/0,
626  Whitespaces);
627  }
628  return;
629  }
630  // Here no reflow with the previous line will happen.
631  // Fix the decoration of the line at LineIndex.
632  StringRef Prefix = Decoration;
633  if (Content[LineIndex].empty()) {
634  if (LineIndex + 1 == Lines.size()) {
635  if (!LastLineNeedsDecoration) {
636  // If the last line was empty, we don't need a prefix, as the */ will
637  // line up with the decoration (if it exists).
638  Prefix = "";
639  }
640  } else if (!Decoration.empty()) {
641  // For other empty lines, if we do have a decoration, adapt it to not
642  // contain a trailing whitespace.
643  Prefix = Prefix.substr(0, 1);
644  }
645  } else {
646  if (ContentColumn[LineIndex] == 1) {
647  // This line starts immediately after the decorating *.
648  Prefix = Prefix.substr(0, 1);
649  }
650  }
651  // This is the offset of the end of the last line relative to the start of the
652  // token text in the token.
653  unsigned WhitespaceOffsetInToken = Content[LineIndex - 1].data() +
654  Content[LineIndex - 1].size() -
655  tokenAt(LineIndex).TokenText.data();
656  unsigned WhitespaceLength = Content[LineIndex].data() -
657  tokenAt(LineIndex).TokenText.data() -
658  WhitespaceOffsetInToken;
659  Whitespaces.replaceWhitespaceInToken(
660  tokenAt(LineIndex), WhitespaceOffsetInToken, WhitespaceLength, "", Prefix,
661  InPPDirective, /*Newlines=*/1, ContentColumn[LineIndex] - Prefix.size());
662 }
663 
664 BreakableToken::Split
666  if (DelimitersOnNewline) {
667  // Replace the trailing whitespace of the last line with a newline.
668  // In case the last line is empty, the ending '*/' is already on its own
669  // line.
670  StringRef Line = Content.back().substr(TailOffset);
671  StringRef TrimmedLine = Line.rtrim(Blanks);
672  if (!TrimmedLine.empty())
673  return Split(TrimmedLine.size(), Line.size() - TrimmedLine.size());
674  }
675  return Split(StringRef::npos, 0);
676 }
677 
678 bool BreakableBlockComment::mayReflow(unsigned LineIndex,
679  llvm::Regex &CommentPragmasRegex) const {
680  // Content[LineIndex] may exclude the indent after the '*' decoration. In that
681  // case, we compute the start of the comment pragma manually.
682  StringRef IndentContent = Content[LineIndex];
683  if (Lines[LineIndex].ltrim(Blanks).startswith("*")) {
684  IndentContent = Lines[LineIndex].ltrim(Blanks).substr(1);
685  }
686  return LineIndex > 0 && !CommentPragmasRegex.match(IndentContent) &&
687  mayReflowContent(Content[LineIndex]) && !Tok.Finalized &&
688  !switchesFormatting(tokenAt(LineIndex));
689 }
690 
692  const FormatToken &Token, unsigned StartColumn,
693  unsigned OriginalStartColumn, bool FirstInLine, bool InPPDirective,
695  : BreakableComment(Token, StartColumn, InPPDirective, Encoding, Style) {
696  assert(Tok.is(TT_LineComment) &&
697  "line comment section must start with a line comment");
698  FormatToken *LineTok = nullptr;
699  for (const FormatToken *CurrentTok = &Tok;
700  CurrentTok && CurrentTok->is(TT_LineComment);
701  CurrentTok = CurrentTok->Next) {
702  LastLineTok = LineTok;
703  StringRef TokenText(CurrentTok->TokenText);
704  assert((TokenText.startswith("//") || TokenText.startswith("#")) &&
705  "unsupported line comment prefix, '//' and '#' are supported");
706  size_t FirstLineIndex = Lines.size();
707  TokenText.split(Lines, "\n");
708  Content.resize(Lines.size());
709  ContentColumn.resize(Lines.size());
710  OriginalContentColumn.resize(Lines.size());
711  Tokens.resize(Lines.size());
712  Prefix.resize(Lines.size());
713  OriginalPrefix.resize(Lines.size());
714  for (size_t i = FirstLineIndex, e = Lines.size(); i < e; ++i) {
715  Lines[i] = Lines[i].ltrim(Blanks);
716  // We need to trim the blanks in case this is not the first line in a
717  // multiline comment. Then the indent is included in Lines[i].
718  StringRef IndentPrefix =
719  getLineCommentIndentPrefix(Lines[i].ltrim(Blanks), Style);
720  assert((TokenText.startswith("//") || TokenText.startswith("#")) &&
721  "unsupported line comment prefix, '//' and '#' are supported");
722  OriginalPrefix[i] = Prefix[i] = IndentPrefix;
723  if (Lines[i].size() > Prefix[i].size() &&
724  isAlphanumeric(Lines[i][Prefix[i].size()])) {
725  if (Prefix[i] == "//")
726  Prefix[i] = "// ";
727  else if (Prefix[i] == "///")
728  Prefix[i] = "/// ";
729  else if (Prefix[i] == "//!")
730  Prefix[i] = "//! ";
731  else if (Prefix[i] == "///<")
732  Prefix[i] = "///< ";
733  else if (Prefix[i] == "//!<")
734  Prefix[i] = "//!< ";
735  else if (Prefix[i] == "#" &&
737  Prefix[i] = "# ";
738  }
739 
740  Tokens[i] = LineTok;
741  Content[i] = Lines[i].substr(IndentPrefix.size());
742  OriginalContentColumn[i] =
743  StartColumn + encoding::columnWidthWithTabs(OriginalPrefix[i],
744  StartColumn,
745  Style.TabWidth, Encoding);
746  ContentColumn[i] =
747  StartColumn + encoding::columnWidthWithTabs(Prefix[i], StartColumn,
748  Style.TabWidth, Encoding);
749 
750  // Calculate the end of the non-whitespace text in this line.
751  size_t EndOfLine = Content[i].find_last_not_of(Blanks);
752  if (EndOfLine == StringRef::npos)
753  EndOfLine = Content[i].size();
754  else
755  ++EndOfLine;
756  Content[i] = Content[i].substr(0, EndOfLine);
757  }
758  LineTok = CurrentTok->Next;
759  if (CurrentTok->Next && !CurrentTok->Next->ContinuesLineCommentSection) {
760  // A line comment section needs to broken by a line comment that is
761  // preceded by at least two newlines. Note that we put this break here
762  // instead of breaking at a previous stage during parsing, since that
763  // would split the contents of the enum into two unwrapped lines in this
764  // example, which is undesirable:
765  // enum A {
766  // a, // comment about a
767  //
768  // // comment about b
769  // b
770  // };
771  //
772  // FIXME: Consider putting separate line comment sections as children to
773  // the unwrapped line instead.
774  break;
775  }
776  }
777 }
778 
779 unsigned
781  StringRef::size_type Length,
782  unsigned StartColumn) const {
784  Content[LineIndex].substr(Offset, Length), StartColumn, Style.TabWidth,
785  Encoding);
786 }
787 
789  bool Break) const {
790  if (Break)
791  return OriginalContentColumn[LineIndex];
792  return ContentColumn[LineIndex];
793 }
794 
796  unsigned LineIndex, unsigned TailOffset, Split Split,
797  unsigned ContentIndent, WhitespaceManager &Whitespaces) const {
798  StringRef Text = Content[LineIndex].substr(TailOffset);
799  // Compute the offset of the split relative to the beginning of the token
800  // text.
801  unsigned BreakOffsetInToken =
802  Text.data() - tokenAt(LineIndex).TokenText.data() + Split.first;
803  unsigned CharsToRemove = Split.second;
804  // Compute the size of the new indent, including the size of the new prefix of
805  // the newly broken line.
806  unsigned IndentAtLineBreak = OriginalContentColumn[LineIndex] +
807  Prefix[LineIndex].size() -
808  OriginalPrefix[LineIndex].size();
809  assert(IndentAtLineBreak >= Prefix[LineIndex].size());
810  Whitespaces.replaceWhitespaceInToken(
811  tokenAt(LineIndex), BreakOffsetInToken, CharsToRemove, "",
812  Prefix[LineIndex], InPPDirective, /*Newlines=*/1,
813  /*Spaces=*/IndentAtLineBreak - Prefix[LineIndex].size());
814 }
815 
817  unsigned LineIndex, llvm::Regex &CommentPragmasRegex) const {
818  if (!mayReflow(LineIndex, CommentPragmasRegex))
819  return Split(StringRef::npos, 0);
820 
821  size_t Trimmed = Content[LineIndex].find_first_not_of(Blanks);
822 
823  // In a line comment section each line is a separate token; thus, after a
824  // split we replace all whitespace before the current line comment token
825  // (which does not need to be included in the split), plus the start of the
826  // line up to where the content starts.
827  return Split(0, Trimmed != StringRef::npos ? Trimmed : 0);
828 }
829 
830 void BreakableLineCommentSection::reflow(unsigned LineIndex,
831  WhitespaceManager &Whitespaces) const {
832  if (LineIndex > 0 && Tokens[LineIndex] != Tokens[LineIndex - 1]) {
833  // Reflow happens between tokens. Replace the whitespace between the
834  // tokens by the empty string.
835  Whitespaces.replaceWhitespace(
836  *Tokens[LineIndex], /*Newlines=*/0, /*Spaces=*/0,
837  /*StartOfTokenColumn=*/StartColumn, /*InPPDirective=*/false);
838  } else if (LineIndex > 0) {
839  // In case we're reflowing after the '\' in:
840  //
841  // // line comment \
842  // // line 2
843  //
844  // the reflow happens inside the single comment token (it is a single line
845  // comment with an unescaped newline).
846  // Replace the whitespace between the '\' and '//' with the empty string.
847  //
848  // Offset points to after the '\' relative to start of the token.
849  unsigned Offset = Lines[LineIndex - 1].data() +
850  Lines[LineIndex - 1].size() -
851  tokenAt(LineIndex - 1).TokenText.data();
852  // WhitespaceLength is the number of chars between the '\' and the '//' on
853  // the next line.
854  unsigned WhitespaceLength =
855  Lines[LineIndex].data() - tokenAt(LineIndex).TokenText.data() - Offset;
856  Whitespaces.replaceWhitespaceInToken(*Tokens[LineIndex],
857  Offset,
858  /*ReplaceChars=*/WhitespaceLength,
859  /*PreviousPostfix=*/"",
860  /*CurrentPrefix=*/"",
861  /*InPPDirective=*/false,
862  /*Newlines=*/0,
863  /*Spaces=*/0);
864 
865  }
866  // Replace the indent and prefix of the token with the reflow prefix.
867  unsigned Offset =
868  Lines[LineIndex].data() - tokenAt(LineIndex).TokenText.data();
869  unsigned WhitespaceLength =
870  Content[LineIndex].data() - Lines[LineIndex].data();
871  Whitespaces.replaceWhitespaceInToken(*Tokens[LineIndex],
872  Offset,
873  /*ReplaceChars=*/WhitespaceLength,
874  /*PreviousPostfix=*/"",
875  /*CurrentPrefix=*/ReflowPrefix,
876  /*InPPDirective=*/false,
877  /*Newlines=*/0,
878  /*Spaces=*/0);
879 }
880 
882  unsigned LineIndex, WhitespaceManager &Whitespaces) const {
883  // If this is the first line of a token, we need to inform Whitespace Manager
884  // about it: either adapt the whitespace range preceding it, or mark it as an
885  // untouchable token.
886  // This happens for instance here:
887  // // line 1 \
888  // // line 2
889  if (LineIndex > 0 && Tokens[LineIndex] != Tokens[LineIndex - 1]) {
890  // This is the first line for the current token, but no reflow with the
891  // previous token is necessary. However, we still may need to adjust the
892  // start column. Note that ContentColumn[LineIndex] is the expected
893  // content column after a possible update to the prefix, hence the prefix
894  // length change is included.
895  unsigned LineColumn =
896  ContentColumn[LineIndex] -
897  (Content[LineIndex].data() - Lines[LineIndex].data()) +
898  (OriginalPrefix[LineIndex].size() - Prefix[LineIndex].size());
899 
900  // We always want to create a replacement instead of adding an untouchable
901  // token, even if LineColumn is the same as the original column of the
902  // token. This is because WhitespaceManager doesn't align trailing
903  // comments if they are untouchable.
904  Whitespaces.replaceWhitespace(*Tokens[LineIndex],
905  /*Newlines=*/1,
906  /*Spaces=*/LineColumn,
907  /*StartOfTokenColumn=*/LineColumn,
908  /*InPPDirective=*/false);
909  }
910  if (OriginalPrefix[LineIndex] != Prefix[LineIndex]) {
911  // Adjust the prefix if necessary.
912 
913  // Take care of the space possibly introduced after a decoration.
914  assert(Prefix[LineIndex] == (OriginalPrefix[LineIndex] + " ").str() &&
915  "Expecting a line comment prefix to differ from original by at most "
916  "a space");
917  Whitespaces.replaceWhitespaceInToken(
918  tokenAt(LineIndex), OriginalPrefix[LineIndex].size(), 0, "", "",
919  /*InPPDirective=*/false, /*Newlines=*/0, /*Spaces=*/1);
920  }
921 }
922 
924  if (LastLineTok) {
925  State.NextToken = LastLineTok->Next;
926  }
927 }
928 
930  unsigned LineIndex, llvm::Regex &CommentPragmasRegex) const {
931  // Line comments have the indent as part of the prefix, so we need to
932  // recompute the start of the line.
933  StringRef IndentContent = Content[LineIndex];
934  if (Lines[LineIndex].startswith("//")) {
935  IndentContent = Lines[LineIndex].substr(2);
936  }
937  // FIXME: Decide whether we want to reflow non-regular indents:
938  // Currently, we only reflow when the OriginalPrefix[LineIndex] matches the
939  // OriginalPrefix[LineIndex-1]. That means we don't reflow
940  // // text that protrudes
941  // // into text with different indent
942  // We do reflow in that case in block comments.
943  return LineIndex > 0 && !CommentPragmasRegex.match(IndentContent) &&
944  mayReflowContent(Content[LineIndex]) && !Tok.Finalized &&
945  !switchesFormatting(tokenAt(LineIndex)) &&
946  OriginalPrefix[LineIndex] == OriginalPrefix[LineIndex - 1];
947 }
948 
949 } // namespace format
950 } // namespace clang
unsigned getLineCount() const override
bool switchesFormatting(const FormatToken &Token)
Checks if Token switches formatting, like /* clang-format off.
Declares BreakableToken, BreakableStringLiteral, BreakableComment, BreakableBlockComment and Breakabl...
Split getSplitAfterLastLine(unsigned TailOffset) const override
static const char *const Blanks
static const llvm::StringSet ContentIndentingJavadocAnnotations
void adaptStartOfLine(unsigned LineIndex, WhitespaceManager &Whitespaces) const override
bool introducesBreakBeforeToken() const override
unsigned getRemainingLength(unsigned LineIndex, unsigned Offset, unsigned StartColumn) const override
void reflow(unsigned LineIndex, WhitespaceManager &Whitespaces) const override
Split getSplit(unsigned LineIndex, unsigned TailOffset, unsigned ColumnLimit, unsigned ContentStartColumn, llvm::Regex &CommentPragmasRegex) const override
const FormatToken & tokenAt(unsigned LineIndex) const
BreakableBlockComment(const FormatToken &Token, unsigned StartColumn, unsigned OriginalStartColumn, bool FirstInLine, bool InPPDirective, encoding::Encoding Encoding, const FormatStyle &Style)
FormatToken * Next
The next token in the unwrapped line.
Definition: FormatToken.h:296
static StringRef getLineCommentIndentPrefix(StringRef Comment, const FormatStyle &Style)
void replaceWhitespaceInToken(const FormatToken &Tok, unsigned Offset, unsigned ReplaceChars, StringRef PreviousPostfix, StringRef CurrentPrefix, bool InPPDirective, unsigned Newlines, int Spaces)
Inserts or replaces whitespace in the middle of a token.
SmallVector< int, 16 > ContentColumn
Split getReflowSplit(unsigned LineIndex, llvm::Regex &CommentPragmasRegex) const override
LineState State
Should be used for Java.
Definition: Format.h:1184
void updateNextToken(LineState &State) const override
unsigned getContentStartColumn(unsigned LineIndex, bool Break) const override
Token - This structure provides full information about a lexed token.
Definition: Token.h:35
unsigned columnWidthWithTabs(StringRef Text, unsigned StartColumn, unsigned TabWidth, Encoding Encoding)
Returns the number of columns required to display the Text, starting from the StartColumn on a termin...
Definition: Encoding.h:62
Manages the whitespaces around tokens and their replacements.
void insertBreak(unsigned LineIndex, unsigned TailOffset, Split Split, unsigned ContentIndent, WhitespaceManager &Whitespaces) const override
uint32_t Offset
Definition: CacheTokens.cpp:43
const FormatToken & Tok
bool mayReflow(unsigned LineIndex, llvm::Regex &CommentPragmasRegex) const override
Split getReflowSplit(unsigned LineIndex, llvm::Regex &CommentPragmasRegex) const override
unsigned ColumnLimit
The column limit.
Definition: Format.h:885
The current state when indenting a unwrapped line.
void insertBreak(unsigned LineIndex, unsigned TailOffset, Split Split, unsigned ContentIndent, WhitespaceManager &Whitespaces) const override
SmallVector< StringRef, 16 > Content
Should be used for JavaScript.
Definition: Format.h:1186
const AnnotatedLine * Line
unsigned getEscapeSequenceLength(StringRef Text)
Gets the length of an escape sequence inside a C++ string literal.
Definition: Encoding.h:97
A wrapper around a Token storing information about the whitespace characters preceding it...
Definition: FormatToken.h:123
LLVM_READONLY bool isAlphanumeric(unsigned char c)
Return true if this character is an ASCII letter or digit: [a-zA-Z0-9].
Definition: CharInfo.h:118
unsigned getCodePointNumBytes(char FirstChar, Encoding Encoding)
Gets the number of bytes in a sequence representing a single codepoint and starting with FirstChar in...
Definition: Encoding.h:78
void replaceWhitespace(FormatToken &Tok, unsigned Newlines, unsigned Spaces, unsigned StartOfTokenColumn, bool InPPDirective=false)
Replaces the whitespace in front of Tok.
SmallVector< FormatToken *, 16 > Tokens
#define false
Definition: stdbool.h:33
void adaptStartOfLine(unsigned LineIndex, WhitespaceManager &Whitespaces) const override
bool is(tok::TokenKind Kind) const
Definition: FormatToken.h:310
const bool InPPDirective
Various functions to configurably format source code.
unsigned getRangeLength(unsigned LineIndex, unsigned Offset, StringRef::size_type Length, unsigned StartColumn) const override
void compressWhitespace(unsigned LineIndex, unsigned TailOffset, Split Split, WhitespaceManager &Whitespaces) const override
BreakableComment(const FormatToken &Token, unsigned StartColumn, bool InPPDirective, encoding::Encoding Encoding, const FormatStyle &Style)
Creates a breakable token for a comment.
unsigned ContinuationIndentWidth
Indent width for line continuations.
Definition: Format.h:981
unsigned getRangeLength(unsigned LineIndex, unsigned Offset, StringRef::size_type Length, unsigned StartColumn) const override
StringRef TokenText
The raw text of the token.
Definition: FormatToken.h:171
Split getSplit(unsigned LineIndex, unsigned TailOffset, unsigned ColumnLimit, unsigned ContentStartColumn, llvm::Regex &CommentPragmasRegex) const override
BreakableStringLiteral(const FormatToken &Tok, unsigned StartColumn, StringRef Prefix, StringRef Postfix, unsigned UnbreakableTailLength, bool InPPDirective, encoding::Encoding Encoding, const FormatStyle &Style)
Creates a breakable token for a single line string literal.
BreakableLineCommentSection(const FormatToken &Token, unsigned StartColumn, unsigned OriginalStartColumn, bool FirstInLine, bool InPPDirective, encoding::Encoding Encoding, const FormatStyle &Style)
The FormatStyle is used to configure the formatting to follow specific guidelines.
Definition: Format.h:48
static bool mayReflowContent(StringRef Content)
LanguageKind Language
Language, this format style is targeted at.
Definition: Format.h:1201
Dataflow Directional Tag Classes.
unsigned getContentStartColumn(unsigned LineIndex, bool Break) const override
bool Finalized
If true, this token has been fully formatted (indented and potentially re-formatted inside)...
Definition: FormatToken.h:308
unsigned getLengthAfterCompression(unsigned RemainingTokenColumns, Split Split) const
Returns the number of columns needed to format RemainingTokenColumns, assuming that Split is within t...
unsigned getRangeLength(unsigned LineIndex, unsigned Offset, StringRef::size_type Length, unsigned StartColumn) const override
void insertBreak(unsigned LineIndex, unsigned TailOffset, Split Split, unsigned ContentIndent, WhitespaceManager &Whitespaces) const override
unsigned TabWidth
The number of columns used for tab stops.
Definition: Format.h:1657
unsigned getRemainingLength(unsigned LineIndex, unsigned Offset, unsigned StartColumn) const override
void reflow(unsigned LineIndex, WhitespaceManager &Whitespaces) const override
bool mayReflow(unsigned LineIndex, llvm::Regex &CommentPragmasRegex) const override
static bool IsBlank(char C)
LLVM_READONLY bool isPunctuation(unsigned char c)
Return true if this character is an ASCII punctuation character.
Definition: CharInfo.h:132
unsigned getContentStartColumn(unsigned LineIndex, bool Break) const override
static BreakableToken::Split getStringSplit(StringRef Text, unsigned UsedColumns, unsigned ColumnLimit, unsigned TabWidth, encoding::Encoding Encoding)
unsigned getContentIndent(unsigned LineIndex) const override
__DEVICE__ int max(int __a, int __b)
unsigned getLineCount() const override
Should be used for Protocol Buffer messages in text format (https://developers.google.com/protocol-buffers/).
Definition: Format.h:1196
BreakableToken(const FormatToken &Tok, bool InPPDirective, encoding::Encoding Encoding, const FormatStyle &Style)
StringRef Text
Definition: Format.cpp:1606
FormatToken * NextToken
The token that needs to be next formatted.
static BreakableToken::Split getCommentSplit(StringRef Text, unsigned ContentStartColumn, unsigned ColumnLimit, unsigned TabWidth, encoding::Encoding Encoding)
This file implements an indenter that manages the indentation of continuations.
SmallVector< StringRef, 16 > Lines
const encoding::Encoding Encoding
const FormatStyle & Style