xref: /freebsd/contrib/llvm-project/clang/lib/Format/BreakableToken.cpp (revision 9f23cbd6cae82fd77edfad7173432fa8dccd0a95)
1 //===--- BreakableToken.cpp - Format C++ code -----------------------------===//
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 /// \file
10 /// Contains implementation of BreakableToken class and classes derived
11 /// from it.
12 ///
13 //===----------------------------------------------------------------------===//
14 
15 #include "BreakableToken.h"
16 #include "ContinuationIndenter.h"
17 #include "clang/Basic/CharInfo.h"
18 #include "clang/Format/Format.h"
19 #include "llvm/ADT/STLExtras.h"
20 #include "llvm/Support/Debug.h"
21 #include <algorithm>
22 
23 #define DEBUG_TYPE "format-token-breaker"
24 
25 namespace clang {
26 namespace format {
27 
28 static constexpr StringRef Blanks = " \t\v\f\r";
29 static bool IsBlank(char C) {
30   switch (C) {
31   case ' ':
32   case '\t':
33   case '\v':
34   case '\f':
35   case '\r':
36     return true;
37   default:
38     return false;
39   }
40 }
41 
42 static StringRef getLineCommentIndentPrefix(StringRef Comment,
43                                             const FormatStyle &Style) {
44   static constexpr StringRef KnownCStylePrefixes[] = {"///<", "//!<", "///",
45                                                       "//!",  "//:",  "//"};
46   static constexpr StringRef KnownTextProtoPrefixes[] = {"####", "###", "##",
47                                                          "//", "#"};
48   ArrayRef<StringRef> KnownPrefixes(KnownCStylePrefixes);
49   if (Style.Language == FormatStyle::LK_TextProto)
50     KnownPrefixes = KnownTextProtoPrefixes;
51 
52   assert(
53       llvm::is_sorted(KnownPrefixes, [](StringRef Lhs, StringRef Rhs) noexcept {
54         return Lhs.size() > Rhs.size();
55       }));
56 
57   for (StringRef KnownPrefix : KnownPrefixes) {
58     if (Comment.startswith(KnownPrefix)) {
59       const auto PrefixLength =
60           Comment.find_first_not_of(' ', KnownPrefix.size());
61       return Comment.substr(0, PrefixLength);
62     }
63   }
64   return {};
65 }
66 
67 static BreakableToken::Split
68 getCommentSplit(StringRef Text, unsigned ContentStartColumn,
69                 unsigned ColumnLimit, unsigned TabWidth,
70                 encoding::Encoding Encoding, const FormatStyle &Style,
71                 bool DecorationEndsWithStar = false) {
72   LLVM_DEBUG(llvm::dbgs() << "Comment split: \"" << Text
73                           << "\", Column limit: " << ColumnLimit
74                           << ", Content start: " << ContentStartColumn << "\n");
75   if (ColumnLimit <= ContentStartColumn + 1)
76     return BreakableToken::Split(StringRef::npos, 0);
77 
78   unsigned MaxSplit = ColumnLimit - ContentStartColumn + 1;
79   unsigned MaxSplitBytes = 0;
80 
81   for (unsigned NumChars = 0;
82        NumChars < MaxSplit && MaxSplitBytes < Text.size();) {
83     unsigned BytesInChar =
84         encoding::getCodePointNumBytes(Text[MaxSplitBytes], Encoding);
85     NumChars +=
86         encoding::columnWidthWithTabs(Text.substr(MaxSplitBytes, BytesInChar),
87                                       ContentStartColumn, TabWidth, Encoding);
88     MaxSplitBytes += BytesInChar;
89   }
90 
91   // In JavaScript, some @tags can be followed by {, and machinery that parses
92   // these comments will fail to understand the comment if followed by a line
93   // break. So avoid ever breaking before a {.
94   if (Style.isJavaScript()) {
95     StringRef::size_type SpaceOffset =
96         Text.find_first_of(Blanks, MaxSplitBytes);
97     if (SpaceOffset != StringRef::npos && SpaceOffset + 1 < Text.size() &&
98         Text[SpaceOffset + 1] == '{') {
99       MaxSplitBytes = SpaceOffset + 1;
100     }
101   }
102 
103   StringRef::size_type SpaceOffset = Text.find_last_of(Blanks, MaxSplitBytes);
104 
105   static const auto kNumberedListRegexp = llvm::Regex("^[1-9][0-9]?\\.");
106   // Some spaces are unacceptable to break on, rewind past them.
107   while (SpaceOffset != StringRef::npos) {
108     // If a line-comment ends with `\`, the next line continues the comment,
109     // whether or not it starts with `//`. This is confusing and triggers
110     // -Wcomment.
111     // Avoid introducing multiline comments by not allowing a break right
112     // after '\'.
113     if (Style.isCpp()) {
114       StringRef::size_type LastNonBlank =
115           Text.find_last_not_of(Blanks, SpaceOffset);
116       if (LastNonBlank != StringRef::npos && Text[LastNonBlank] == '\\') {
117         SpaceOffset = Text.find_last_of(Blanks, LastNonBlank);
118         continue;
119       }
120     }
121 
122     // Do not split before a number followed by a dot: this would be interpreted
123     // as a numbered list, which would prevent re-flowing in subsequent passes.
124     if (kNumberedListRegexp.match(Text.substr(SpaceOffset).ltrim(Blanks))) {
125       SpaceOffset = Text.find_last_of(Blanks, SpaceOffset);
126       continue;
127     }
128 
129     // Avoid ever breaking before a @tag or a { in JavaScript.
130     if (Style.isJavaScript() && SpaceOffset + 1 < Text.size() &&
131         (Text[SpaceOffset + 1] == '{' || Text[SpaceOffset + 1] == '@')) {
132       SpaceOffset = Text.find_last_of(Blanks, SpaceOffset);
133       continue;
134     }
135 
136     break;
137   }
138 
139   if (SpaceOffset == StringRef::npos ||
140       // Don't break at leading whitespace.
141       Text.find_last_not_of(Blanks, SpaceOffset) == StringRef::npos) {
142     // Make sure that we don't break at leading whitespace that
143     // reaches past MaxSplit.
144     StringRef::size_type FirstNonWhitespace = Text.find_first_not_of(Blanks);
145     if (FirstNonWhitespace == StringRef::npos) {
146       // If the comment is only whitespace, we cannot split.
147       return BreakableToken::Split(StringRef::npos, 0);
148     }
149     SpaceOffset = Text.find_first_of(
150         Blanks, std::max<unsigned>(MaxSplitBytes, FirstNonWhitespace));
151   }
152   if (SpaceOffset != StringRef::npos && SpaceOffset != 0) {
153     // adaptStartOfLine will break after lines starting with /** if the comment
154     // is broken anywhere. Avoid emitting this break twice here.
155     // Example: in /** longtextcomesherethatbreaks */ (with ColumnLimit 20) will
156     // insert a break after /**, so this code must not insert the same break.
157     if (SpaceOffset == 1 && Text[SpaceOffset - 1] == '*')
158       return BreakableToken::Split(StringRef::npos, 0);
159     StringRef BeforeCut = Text.substr(0, SpaceOffset).rtrim(Blanks);
160     StringRef AfterCut = Text.substr(SpaceOffset);
161     // Don't trim the leading blanks if it would create a */ after the break.
162     if (!DecorationEndsWithStar || AfterCut.size() <= 1 || AfterCut[1] != '/')
163       AfterCut = AfterCut.ltrim(Blanks);
164     return BreakableToken::Split(BeforeCut.size(),
165                                  AfterCut.begin() - BeforeCut.end());
166   }
167   return BreakableToken::Split(StringRef::npos, 0);
168 }
169 
170 static BreakableToken::Split
171 getStringSplit(StringRef Text, unsigned UsedColumns, unsigned ColumnLimit,
172                unsigned TabWidth, encoding::Encoding Encoding) {
173   // FIXME: Reduce unit test case.
174   if (Text.empty())
175     return BreakableToken::Split(StringRef::npos, 0);
176   if (ColumnLimit <= UsedColumns)
177     return BreakableToken::Split(StringRef::npos, 0);
178   unsigned MaxSplit = ColumnLimit - UsedColumns;
179   StringRef::size_type SpaceOffset = 0;
180   StringRef::size_type SlashOffset = 0;
181   StringRef::size_type WordStartOffset = 0;
182   StringRef::size_type SplitPoint = 0;
183   for (unsigned Chars = 0;;) {
184     unsigned Advance;
185     if (Text[0] == '\\') {
186       Advance = encoding::getEscapeSequenceLength(Text);
187       Chars += Advance;
188     } else {
189       Advance = encoding::getCodePointNumBytes(Text[0], Encoding);
190       Chars += encoding::columnWidthWithTabs(
191           Text.substr(0, Advance), UsedColumns + Chars, TabWidth, Encoding);
192     }
193 
194     if (Chars > MaxSplit || Text.size() <= Advance)
195       break;
196 
197     if (IsBlank(Text[0]))
198       SpaceOffset = SplitPoint;
199     if (Text[0] == '/')
200       SlashOffset = SplitPoint;
201     if (Advance == 1 && !isAlphanumeric(Text[0]))
202       WordStartOffset = SplitPoint;
203 
204     SplitPoint += Advance;
205     Text = Text.substr(Advance);
206   }
207 
208   if (SpaceOffset != 0)
209     return BreakableToken::Split(SpaceOffset + 1, 0);
210   if (SlashOffset != 0)
211     return BreakableToken::Split(SlashOffset + 1, 0);
212   if (WordStartOffset != 0)
213     return BreakableToken::Split(WordStartOffset + 1, 0);
214   if (SplitPoint != 0)
215     return BreakableToken::Split(SplitPoint, 0);
216   return BreakableToken::Split(StringRef::npos, 0);
217 }
218 
219 bool switchesFormatting(const FormatToken &Token) {
220   assert((Token.is(TT_BlockComment) || Token.is(TT_LineComment)) &&
221          "formatting regions are switched by comment tokens");
222   StringRef Content = Token.TokenText.substr(2).ltrim();
223   return Content.startswith("clang-format on") ||
224          Content.startswith("clang-format off");
225 }
226 
227 unsigned
228 BreakableToken::getLengthAfterCompression(unsigned RemainingTokenColumns,
229                                           Split Split) const {
230   // Example: consider the content
231   // lala  lala
232   // - RemainingTokenColumns is the original number of columns, 10;
233   // - Split is (4, 2), denoting the two spaces between the two words;
234   //
235   // We compute the number of columns when the split is compressed into a single
236   // space, like:
237   // lala lala
238   //
239   // FIXME: Correctly measure the length of whitespace in Split.second so it
240   // works with tabs.
241   return RemainingTokenColumns + 1 - Split.second;
242 }
243 
244 unsigned BreakableStringLiteral::getLineCount() const { return 1; }
245 
246 unsigned BreakableStringLiteral::getRangeLength(unsigned LineIndex,
247                                                 unsigned Offset,
248                                                 StringRef::size_type Length,
249                                                 unsigned StartColumn) const {
250   llvm_unreachable("Getting the length of a part of the string literal "
251                    "indicates that the code tries to reflow it.");
252 }
253 
254 unsigned
255 BreakableStringLiteral::getRemainingLength(unsigned LineIndex, unsigned Offset,
256                                            unsigned StartColumn) const {
257   return UnbreakableTailLength + Postfix.size() +
258          encoding::columnWidthWithTabs(Line.substr(Offset), StartColumn,
259                                        Style.TabWidth, Encoding);
260 }
261 
262 unsigned BreakableStringLiteral::getContentStartColumn(unsigned LineIndex,
263                                                        bool Break) const {
264   return StartColumn + Prefix.size();
265 }
266 
267 BreakableStringLiteral::BreakableStringLiteral(
268     const FormatToken &Tok, unsigned StartColumn, StringRef Prefix,
269     StringRef Postfix, unsigned UnbreakableTailLength, bool InPPDirective,
270     encoding::Encoding Encoding, const FormatStyle &Style)
271     : BreakableToken(Tok, InPPDirective, Encoding, Style),
272       StartColumn(StartColumn), Prefix(Prefix), Postfix(Postfix),
273       UnbreakableTailLength(UnbreakableTailLength) {
274   assert(Tok.TokenText.startswith(Prefix) && Tok.TokenText.endswith(Postfix));
275   Line = Tok.TokenText.substr(
276       Prefix.size(), Tok.TokenText.size() - Prefix.size() - Postfix.size());
277 }
278 
279 BreakableToken::Split BreakableStringLiteral::getSplit(
280     unsigned LineIndex, unsigned TailOffset, unsigned ColumnLimit,
281     unsigned ContentStartColumn, const llvm::Regex &CommentPragmasRegex) const {
282   return getStringSplit(Line.substr(TailOffset), ContentStartColumn,
283                         ColumnLimit - Postfix.size(), Style.TabWidth, Encoding);
284 }
285 
286 void BreakableStringLiteral::insertBreak(unsigned LineIndex,
287                                          unsigned TailOffset, Split Split,
288                                          unsigned ContentIndent,
289                                          WhitespaceManager &Whitespaces) const {
290   Whitespaces.replaceWhitespaceInToken(
291       Tok, Prefix.size() + TailOffset + Split.first, Split.second, Postfix,
292       Prefix, InPPDirective, 1, StartColumn);
293 }
294 
295 BreakableComment::BreakableComment(const FormatToken &Token,
296                                    unsigned StartColumn, bool InPPDirective,
297                                    encoding::Encoding Encoding,
298                                    const FormatStyle &Style)
299     : BreakableToken(Token, InPPDirective, Encoding, Style),
300       StartColumn(StartColumn) {}
301 
302 unsigned BreakableComment::getLineCount() const { return Lines.size(); }
303 
304 BreakableToken::Split
305 BreakableComment::getSplit(unsigned LineIndex, unsigned TailOffset,
306                            unsigned ColumnLimit, unsigned ContentStartColumn,
307                            const llvm::Regex &CommentPragmasRegex) const {
308   // Don't break lines matching the comment pragmas regex.
309   if (CommentPragmasRegex.match(Content[LineIndex]))
310     return Split(StringRef::npos, 0);
311   return getCommentSplit(Content[LineIndex].substr(TailOffset),
312                          ContentStartColumn, ColumnLimit, Style.TabWidth,
313                          Encoding, Style);
314 }
315 
316 void BreakableComment::compressWhitespace(
317     unsigned LineIndex, unsigned TailOffset, Split Split,
318     WhitespaceManager &Whitespaces) const {
319   StringRef Text = Content[LineIndex].substr(TailOffset);
320   // Text is relative to the content line, but Whitespaces operates relative to
321   // the start of the corresponding token, so compute the start of the Split
322   // that needs to be compressed into a single space relative to the start of
323   // its token.
324   unsigned BreakOffsetInToken =
325       Text.data() - tokenAt(LineIndex).TokenText.data() + Split.first;
326   unsigned CharsToRemove = Split.second;
327   Whitespaces.replaceWhitespaceInToken(
328       tokenAt(LineIndex), BreakOffsetInToken, CharsToRemove, "", "",
329       /*InPPDirective=*/false, /*Newlines=*/0, /*Spaces=*/1);
330 }
331 
332 const FormatToken &BreakableComment::tokenAt(unsigned LineIndex) const {
333   return Tokens[LineIndex] ? *Tokens[LineIndex] : Tok;
334 }
335 
336 static bool mayReflowContent(StringRef Content) {
337   Content = Content.trim(Blanks);
338   // Lines starting with '@' commonly have special meaning.
339   // Lines starting with '-', '-#', '+' or '*' are bulleted/numbered lists.
340   bool hasSpecialMeaningPrefix = false;
341   for (StringRef Prefix :
342        {"@", "TODO", "FIXME", "XXX", "-# ", "- ", "+ ", "* "}) {
343     if (Content.startswith(Prefix)) {
344       hasSpecialMeaningPrefix = true;
345       break;
346     }
347   }
348 
349   // Numbered lists may also start with a number followed by '.'
350   // To avoid issues if a line starts with a number which is actually the end
351   // of a previous line, we only consider numbers with up to 2 digits.
352   static const auto kNumberedListRegexp = llvm::Regex("^[1-9][0-9]?\\. ");
353   hasSpecialMeaningPrefix =
354       hasSpecialMeaningPrefix || kNumberedListRegexp.match(Content);
355 
356   // Simple heuristic for what to reflow: content should contain at least two
357   // characters and either the first or second character must be
358   // non-punctuation.
359   return Content.size() >= 2 && !hasSpecialMeaningPrefix &&
360          !Content.endswith("\\") &&
361          // Note that this is UTF-8 safe, since if isPunctuation(Content[0]) is
362          // true, then the first code point must be 1 byte long.
363          (!isPunctuation(Content[0]) || !isPunctuation(Content[1]));
364 }
365 
366 BreakableBlockComment::BreakableBlockComment(
367     const FormatToken &Token, unsigned StartColumn,
368     unsigned OriginalStartColumn, bool FirstInLine, bool InPPDirective,
369     encoding::Encoding Encoding, const FormatStyle &Style, bool UseCRLF)
370     : BreakableComment(Token, StartColumn, InPPDirective, Encoding, Style),
371       DelimitersOnNewline(false),
372       UnbreakableTailLength(Token.UnbreakableTailLength) {
373   assert(Tok.is(TT_BlockComment) &&
374          "block comment section must start with a block comment");
375 
376   StringRef TokenText(Tok.TokenText);
377   assert(TokenText.startswith("/*") && TokenText.endswith("*/"));
378   TokenText.substr(2, TokenText.size() - 4)
379       .split(Lines, UseCRLF ? "\r\n" : "\n");
380 
381   int IndentDelta = StartColumn - OriginalStartColumn;
382   Content.resize(Lines.size());
383   Content[0] = Lines[0];
384   ContentColumn.resize(Lines.size());
385   // Account for the initial '/*'.
386   ContentColumn[0] = StartColumn + 2;
387   Tokens.resize(Lines.size());
388   for (size_t i = 1; i < Lines.size(); ++i)
389     adjustWhitespace(i, IndentDelta);
390 
391   // Align decorations with the column of the star on the first line,
392   // that is one column after the start "/*".
393   DecorationColumn = StartColumn + 1;
394 
395   // Account for comment decoration patterns like this:
396   //
397   // /*
398   // ** blah blah blah
399   // */
400   if (Lines.size() >= 2 && Content[1].startswith("**") &&
401       static_cast<unsigned>(ContentColumn[1]) == StartColumn) {
402     DecorationColumn = StartColumn;
403   }
404 
405   Decoration = "* ";
406   if (Lines.size() == 1 && !FirstInLine) {
407     // Comments for which FirstInLine is false can start on arbitrary column,
408     // and available horizontal space can be too small to align consecutive
409     // lines with the first one.
410     // FIXME: We could, probably, align them to current indentation level, but
411     // now we just wrap them without stars.
412     Decoration = "";
413   }
414   for (size_t i = 1, e = Content.size(); i < e && !Decoration.empty(); ++i) {
415     const StringRef &Text = Content[i];
416     if (i + 1 == e) {
417       // If the last line is empty, the closing "*/" will have a star.
418       if (Text.empty())
419         break;
420     } else if (!Text.empty() && Decoration.startswith(Text)) {
421       continue;
422     }
423     while (!Text.startswith(Decoration))
424       Decoration = Decoration.drop_back(1);
425   }
426 
427   LastLineNeedsDecoration = true;
428   IndentAtLineBreak = ContentColumn[0] + 1;
429   for (size_t i = 1, e = Lines.size(); i < e; ++i) {
430     if (Content[i].empty()) {
431       if (i + 1 == e) {
432         // Empty last line means that we already have a star as a part of the
433         // trailing */. We also need to preserve whitespace, so that */ is
434         // correctly indented.
435         LastLineNeedsDecoration = false;
436         // Align the star in the last '*/' with the stars on the previous lines.
437         if (e >= 2 && !Decoration.empty())
438           ContentColumn[i] = DecorationColumn;
439       } else if (Decoration.empty()) {
440         // For all other lines, set the start column to 0 if they're empty, so
441         // we do not insert trailing whitespace anywhere.
442         ContentColumn[i] = 0;
443       }
444       continue;
445     }
446 
447     // The first line already excludes the star.
448     // The last line excludes the star if LastLineNeedsDecoration is false.
449     // For all other lines, adjust the line to exclude the star and
450     // (optionally) the first whitespace.
451     unsigned DecorationSize = Decoration.startswith(Content[i])
452                                   ? Content[i].size()
453                                   : Decoration.size();
454     if (DecorationSize)
455       ContentColumn[i] = DecorationColumn + DecorationSize;
456     Content[i] = Content[i].substr(DecorationSize);
457     if (!Decoration.startswith(Content[i])) {
458       IndentAtLineBreak =
459           std::min<int>(IndentAtLineBreak, std::max(0, ContentColumn[i]));
460     }
461   }
462   IndentAtLineBreak = std::max<unsigned>(IndentAtLineBreak, Decoration.size());
463 
464   // Detect a multiline jsdoc comment and set DelimitersOnNewline in that case.
465   if (Style.isJavaScript() || Style.Language == FormatStyle::LK_Java) {
466     if ((Lines[0] == "*" || Lines[0].startswith("* ")) && Lines.size() > 1) {
467       // This is a multiline jsdoc comment.
468       DelimitersOnNewline = true;
469     } else if (Lines[0].startswith("* ") && Lines.size() == 1) {
470       // Detect a long single-line comment, like:
471       // /** long long long */
472       // Below, '2' is the width of '*/'.
473       unsigned EndColumn =
474           ContentColumn[0] +
475           encoding::columnWidthWithTabs(Lines[0], ContentColumn[0],
476                                         Style.TabWidth, Encoding) +
477           2;
478       DelimitersOnNewline = EndColumn > Style.ColumnLimit;
479     }
480   }
481 
482   LLVM_DEBUG({
483     llvm::dbgs() << "IndentAtLineBreak " << IndentAtLineBreak << "\n";
484     llvm::dbgs() << "DelimitersOnNewline " << DelimitersOnNewline << "\n";
485     for (size_t i = 0; i < Lines.size(); ++i) {
486       llvm::dbgs() << i << " |" << Content[i] << "| "
487                    << "CC=" << ContentColumn[i] << "| "
488                    << "IN=" << (Content[i].data() - Lines[i].data()) << "\n";
489     }
490   });
491 }
492 
493 BreakableToken::Split BreakableBlockComment::getSplit(
494     unsigned LineIndex, unsigned TailOffset, unsigned ColumnLimit,
495     unsigned ContentStartColumn, const llvm::Regex &CommentPragmasRegex) const {
496   // Don't break lines matching the comment pragmas regex.
497   if (CommentPragmasRegex.match(Content[LineIndex]))
498     return Split(StringRef::npos, 0);
499   return getCommentSplit(Content[LineIndex].substr(TailOffset),
500                          ContentStartColumn, ColumnLimit, Style.TabWidth,
501                          Encoding, Style, Decoration.endswith("*"));
502 }
503 
504 void BreakableBlockComment::adjustWhitespace(unsigned LineIndex,
505                                              int IndentDelta) {
506   // When in a preprocessor directive, the trailing backslash in a block comment
507   // is not needed, but can serve a purpose of uniformity with necessary escaped
508   // newlines outside the comment. In this case we remove it here before
509   // trimming the trailing whitespace. The backslash will be re-added later when
510   // inserting a line break.
511   size_t EndOfPreviousLine = Lines[LineIndex - 1].size();
512   if (InPPDirective && Lines[LineIndex - 1].endswith("\\"))
513     --EndOfPreviousLine;
514 
515   // Calculate the end of the non-whitespace text in the previous line.
516   EndOfPreviousLine =
517       Lines[LineIndex - 1].find_last_not_of(Blanks, EndOfPreviousLine);
518   if (EndOfPreviousLine == StringRef::npos)
519     EndOfPreviousLine = 0;
520   else
521     ++EndOfPreviousLine;
522   // Calculate the start of the non-whitespace text in the current line.
523   size_t StartOfLine = Lines[LineIndex].find_first_not_of(Blanks);
524   if (StartOfLine == StringRef::npos)
525     StartOfLine = Lines[LineIndex].size();
526 
527   StringRef Whitespace = Lines[LineIndex].substr(0, StartOfLine);
528   // Adjust Lines to only contain relevant text.
529   size_t PreviousContentOffset =
530       Content[LineIndex - 1].data() - Lines[LineIndex - 1].data();
531   Content[LineIndex - 1] = Lines[LineIndex - 1].substr(
532       PreviousContentOffset, EndOfPreviousLine - PreviousContentOffset);
533   Content[LineIndex] = Lines[LineIndex].substr(StartOfLine);
534 
535   // Adjust the start column uniformly across all lines.
536   ContentColumn[LineIndex] =
537       encoding::columnWidthWithTabs(Whitespace, 0, Style.TabWidth, Encoding) +
538       IndentDelta;
539 }
540 
541 unsigned BreakableBlockComment::getRangeLength(unsigned LineIndex,
542                                                unsigned Offset,
543                                                StringRef::size_type Length,
544                                                unsigned StartColumn) const {
545   return encoding::columnWidthWithTabs(
546       Content[LineIndex].substr(Offset, Length), StartColumn, Style.TabWidth,
547       Encoding);
548 }
549 
550 unsigned BreakableBlockComment::getRemainingLength(unsigned LineIndex,
551                                                    unsigned Offset,
552                                                    unsigned StartColumn) const {
553   unsigned LineLength =
554       UnbreakableTailLength +
555       getRangeLength(LineIndex, Offset, StringRef::npos, StartColumn);
556   if (LineIndex + 1 == Lines.size()) {
557     LineLength += 2;
558     // We never need a decoration when breaking just the trailing "*/" postfix.
559     bool HasRemainingText = Offset < Content[LineIndex].size();
560     if (!HasRemainingText) {
561       bool HasDecoration = Lines[LineIndex].ltrim().startswith(Decoration);
562       if (HasDecoration)
563         LineLength -= Decoration.size();
564     }
565   }
566   return LineLength;
567 }
568 
569 unsigned BreakableBlockComment::getContentStartColumn(unsigned LineIndex,
570                                                       bool Break) const {
571   if (Break)
572     return IndentAtLineBreak;
573   return std::max(0, ContentColumn[LineIndex]);
574 }
575 
576 const llvm::StringSet<>
577     BreakableBlockComment::ContentIndentingJavadocAnnotations = {
578         "@param", "@return",     "@returns", "@throws",  "@type", "@template",
579         "@see",   "@deprecated", "@define",  "@exports", "@mods", "@private",
580 };
581 
582 unsigned BreakableBlockComment::getContentIndent(unsigned LineIndex) const {
583   if (Style.Language != FormatStyle::LK_Java && !Style.isJavaScript())
584     return 0;
585   // The content at LineIndex 0 of a comment like:
586   // /** line 0 */
587   // is "* line 0", so we need to skip over the decoration in that case.
588   StringRef ContentWithNoDecoration = Content[LineIndex];
589   if (LineIndex == 0 && ContentWithNoDecoration.startswith("*"))
590     ContentWithNoDecoration = ContentWithNoDecoration.substr(1).ltrim(Blanks);
591   StringRef FirstWord = ContentWithNoDecoration.substr(
592       0, ContentWithNoDecoration.find_first_of(Blanks));
593   if (ContentIndentingJavadocAnnotations.find(FirstWord) !=
594       ContentIndentingJavadocAnnotations.end()) {
595     return Style.ContinuationIndentWidth;
596   }
597   return 0;
598 }
599 
600 void BreakableBlockComment::insertBreak(unsigned LineIndex, unsigned TailOffset,
601                                         Split Split, unsigned ContentIndent,
602                                         WhitespaceManager &Whitespaces) const {
603   StringRef Text = Content[LineIndex].substr(TailOffset);
604   StringRef Prefix = Decoration;
605   // We need this to account for the case when we have a decoration "* " for all
606   // the lines except for the last one, where the star in "*/" acts as a
607   // decoration.
608   unsigned LocalIndentAtLineBreak = IndentAtLineBreak;
609   if (LineIndex + 1 == Lines.size() &&
610       Text.size() == Split.first + Split.second) {
611     // For the last line we need to break before "*/", but not to add "* ".
612     Prefix = "";
613     if (LocalIndentAtLineBreak >= 2)
614       LocalIndentAtLineBreak -= 2;
615   }
616   // The split offset is from the beginning of the line. Convert it to an offset
617   // from the beginning of the token text.
618   unsigned BreakOffsetInToken =
619       Text.data() - tokenAt(LineIndex).TokenText.data() + Split.first;
620   unsigned CharsToRemove = Split.second;
621   assert(LocalIndentAtLineBreak >= Prefix.size());
622   std::string PrefixWithTrailingIndent = std::string(Prefix);
623   PrefixWithTrailingIndent.append(ContentIndent, ' ');
624   Whitespaces.replaceWhitespaceInToken(
625       tokenAt(LineIndex), BreakOffsetInToken, CharsToRemove, "",
626       PrefixWithTrailingIndent, InPPDirective, /*Newlines=*/1,
627       /*Spaces=*/LocalIndentAtLineBreak + ContentIndent -
628           PrefixWithTrailingIndent.size());
629 }
630 
631 BreakableToken::Split BreakableBlockComment::getReflowSplit(
632     unsigned LineIndex, const llvm::Regex &CommentPragmasRegex) const {
633   if (!mayReflow(LineIndex, CommentPragmasRegex))
634     return Split(StringRef::npos, 0);
635 
636   // If we're reflowing into a line with content indent, only reflow the next
637   // line if its starting whitespace matches the content indent.
638   size_t Trimmed = Content[LineIndex].find_first_not_of(Blanks);
639   if (LineIndex) {
640     unsigned PreviousContentIndent = getContentIndent(LineIndex - 1);
641     if (PreviousContentIndent && Trimmed != StringRef::npos &&
642         Trimmed != PreviousContentIndent) {
643       return Split(StringRef::npos, 0);
644     }
645   }
646 
647   return Split(0, Trimmed != StringRef::npos ? Trimmed : 0);
648 }
649 
650 bool BreakableBlockComment::introducesBreakBeforeToken() const {
651   // A break is introduced when we want delimiters on newline.
652   return DelimitersOnNewline &&
653          Lines[0].substr(1).find_first_not_of(Blanks) != StringRef::npos;
654 }
655 
656 void BreakableBlockComment::reflow(unsigned LineIndex,
657                                    WhitespaceManager &Whitespaces) const {
658   StringRef TrimmedContent = Content[LineIndex].ltrim(Blanks);
659   // Here we need to reflow.
660   assert(Tokens[LineIndex - 1] == Tokens[LineIndex] &&
661          "Reflowing whitespace within a token");
662   // This is the offset of the end of the last line relative to the start of
663   // the token text in the token.
664   unsigned WhitespaceOffsetInToken = Content[LineIndex - 1].data() +
665                                      Content[LineIndex - 1].size() -
666                                      tokenAt(LineIndex).TokenText.data();
667   unsigned WhitespaceLength = TrimmedContent.data() -
668                               tokenAt(LineIndex).TokenText.data() -
669                               WhitespaceOffsetInToken;
670   Whitespaces.replaceWhitespaceInToken(
671       tokenAt(LineIndex), WhitespaceOffsetInToken,
672       /*ReplaceChars=*/WhitespaceLength, /*PreviousPostfix=*/"",
673       /*CurrentPrefix=*/ReflowPrefix, InPPDirective, /*Newlines=*/0,
674       /*Spaces=*/0);
675 }
676 
677 void BreakableBlockComment::adaptStartOfLine(
678     unsigned LineIndex, WhitespaceManager &Whitespaces) const {
679   if (LineIndex == 0) {
680     if (DelimitersOnNewline) {
681       // Since we're breaking at index 1 below, the break position and the
682       // break length are the same.
683       // Note: this works because getCommentSplit is careful never to split at
684       // the beginning of a line.
685       size_t BreakLength = Lines[0].substr(1).find_first_not_of(Blanks);
686       if (BreakLength != StringRef::npos) {
687         insertBreak(LineIndex, 0, Split(1, BreakLength), /*ContentIndent=*/0,
688                     Whitespaces);
689       }
690     }
691     return;
692   }
693   // Here no reflow with the previous line will happen.
694   // Fix the decoration of the line at LineIndex.
695   StringRef Prefix = Decoration;
696   if (Content[LineIndex].empty()) {
697     if (LineIndex + 1 == Lines.size()) {
698       if (!LastLineNeedsDecoration) {
699         // If the last line was empty, we don't need a prefix, as the */ will
700         // line up with the decoration (if it exists).
701         Prefix = "";
702       }
703     } else if (!Decoration.empty()) {
704       // For other empty lines, if we do have a decoration, adapt it to not
705       // contain a trailing whitespace.
706       Prefix = Prefix.substr(0, 1);
707     }
708   } else if (ContentColumn[LineIndex] == 1) {
709     // This line starts immediately after the decorating *.
710     Prefix = Prefix.substr(0, 1);
711   }
712   // This is the offset of the end of the last line relative to the start of the
713   // token text in the token.
714   unsigned WhitespaceOffsetInToken = Content[LineIndex - 1].data() +
715                                      Content[LineIndex - 1].size() -
716                                      tokenAt(LineIndex).TokenText.data();
717   unsigned WhitespaceLength = Content[LineIndex].data() -
718                               tokenAt(LineIndex).TokenText.data() -
719                               WhitespaceOffsetInToken;
720   Whitespaces.replaceWhitespaceInToken(
721       tokenAt(LineIndex), WhitespaceOffsetInToken, WhitespaceLength, "", Prefix,
722       InPPDirective, /*Newlines=*/1, ContentColumn[LineIndex] - Prefix.size());
723 }
724 
725 BreakableToken::Split
726 BreakableBlockComment::getSplitAfterLastLine(unsigned TailOffset) const {
727   if (DelimitersOnNewline) {
728     // Replace the trailing whitespace of the last line with a newline.
729     // In case the last line is empty, the ending '*/' is already on its own
730     // line.
731     StringRef Line = Content.back().substr(TailOffset);
732     StringRef TrimmedLine = Line.rtrim(Blanks);
733     if (!TrimmedLine.empty())
734       return Split(TrimmedLine.size(), Line.size() - TrimmedLine.size());
735   }
736   return Split(StringRef::npos, 0);
737 }
738 
739 bool BreakableBlockComment::mayReflow(
740     unsigned LineIndex, const llvm::Regex &CommentPragmasRegex) const {
741   // Content[LineIndex] may exclude the indent after the '*' decoration. In that
742   // case, we compute the start of the comment pragma manually.
743   StringRef IndentContent = Content[LineIndex];
744   if (Lines[LineIndex].ltrim(Blanks).startswith("*"))
745     IndentContent = Lines[LineIndex].ltrim(Blanks).substr(1);
746   return LineIndex > 0 && !CommentPragmasRegex.match(IndentContent) &&
747          mayReflowContent(Content[LineIndex]) && !Tok.Finalized &&
748          !switchesFormatting(tokenAt(LineIndex));
749 }
750 
751 BreakableLineCommentSection::BreakableLineCommentSection(
752     const FormatToken &Token, unsigned StartColumn, bool InPPDirective,
753     encoding::Encoding Encoding, const FormatStyle &Style)
754     : BreakableComment(Token, StartColumn, InPPDirective, Encoding, Style) {
755   assert(Tok.is(TT_LineComment) &&
756          "line comment section must start with a line comment");
757   FormatToken *LineTok = nullptr;
758   const int Minimum = Style.SpacesInLineCommentPrefix.Minimum;
759   // How many spaces we changed in the first line of the section, this will be
760   // applied in all following lines
761   int FirstLineSpaceChange = 0;
762   for (const FormatToken *CurrentTok = &Tok;
763        CurrentTok && CurrentTok->is(TT_LineComment);
764        CurrentTok = CurrentTok->Next) {
765     LastLineTok = LineTok;
766     StringRef TokenText(CurrentTok->TokenText);
767     assert((TokenText.startswith("//") || TokenText.startswith("#")) &&
768            "unsupported line comment prefix, '//' and '#' are supported");
769     size_t FirstLineIndex = Lines.size();
770     TokenText.split(Lines, "\n");
771     Content.resize(Lines.size());
772     ContentColumn.resize(Lines.size());
773     PrefixSpaceChange.resize(Lines.size());
774     Tokens.resize(Lines.size());
775     Prefix.resize(Lines.size());
776     OriginalPrefix.resize(Lines.size());
777     for (size_t i = FirstLineIndex, e = Lines.size(); i < e; ++i) {
778       Lines[i] = Lines[i].ltrim(Blanks);
779       StringRef IndentPrefix = getLineCommentIndentPrefix(Lines[i], Style);
780       OriginalPrefix[i] = IndentPrefix;
781       const int SpacesInPrefix = llvm::count(IndentPrefix, ' ');
782 
783       // This lambda also considers multibyte character that is not handled in
784       // functions like isPunctuation provided by CharInfo.
785       const auto NoSpaceBeforeFirstCommentChar = [&]() {
786         assert(Lines[i].size() > IndentPrefix.size());
787         const char FirstCommentChar = Lines[i][IndentPrefix.size()];
788         const unsigned FirstCharByteSize =
789             encoding::getCodePointNumBytes(FirstCommentChar, Encoding);
790         if (encoding::columnWidth(
791                 Lines[i].substr(IndentPrefix.size(), FirstCharByteSize),
792                 Encoding) != 1) {
793           return false;
794         }
795         // In C-like comments, add a space before #. For example this is useful
796         // to preserve the relative indentation when commenting out code with
797         // #includes.
798         //
799         // In languages using # as the comment leader such as proto, don't
800         // add a space to support patterns like:
801         // #########
802         // # section
803         // #########
804         if (FirstCommentChar == '#' && !TokenText.startswith("#"))
805           return false;
806         return FirstCommentChar == '\\' || isPunctuation(FirstCommentChar) ||
807                isHorizontalWhitespace(FirstCommentChar);
808       };
809 
810       // On the first line of the comment section we calculate how many spaces
811       // are to be added or removed, all lines after that just get only the
812       // change and we will not look at the maximum anymore. Additionally to the
813       // actual first line, we calculate that when the non space Prefix changes,
814       // e.g. from "///" to "//".
815       if (i == 0 || OriginalPrefix[i].rtrim(Blanks) !=
816                         OriginalPrefix[i - 1].rtrim(Blanks)) {
817         if (SpacesInPrefix < Minimum && Lines[i].size() > IndentPrefix.size() &&
818             !NoSpaceBeforeFirstCommentChar()) {
819           FirstLineSpaceChange = Minimum - SpacesInPrefix;
820         } else if (static_cast<unsigned>(SpacesInPrefix) >
821                    Style.SpacesInLineCommentPrefix.Maximum) {
822           FirstLineSpaceChange =
823               Style.SpacesInLineCommentPrefix.Maximum - SpacesInPrefix;
824         } else {
825           FirstLineSpaceChange = 0;
826         }
827       }
828 
829       if (Lines[i].size() != IndentPrefix.size()) {
830         PrefixSpaceChange[i] = FirstLineSpaceChange;
831 
832         if (SpacesInPrefix + PrefixSpaceChange[i] < Minimum) {
833           PrefixSpaceChange[i] +=
834               Minimum - (SpacesInPrefix + PrefixSpaceChange[i]);
835         }
836 
837         assert(Lines[i].size() > IndentPrefix.size());
838         const auto FirstNonSpace = Lines[i][IndentPrefix.size()];
839         const bool IsFormatComment = LineTok && switchesFormatting(*LineTok);
840         const bool LineRequiresLeadingSpace =
841             !NoSpaceBeforeFirstCommentChar() ||
842             (FirstNonSpace == '}' && FirstLineSpaceChange != 0);
843         const bool AllowsSpaceChange =
844             !IsFormatComment &&
845             (SpacesInPrefix != 0 || LineRequiresLeadingSpace);
846 
847         if (PrefixSpaceChange[i] > 0 && AllowsSpaceChange) {
848           Prefix[i] = IndentPrefix.str();
849           Prefix[i].append(PrefixSpaceChange[i], ' ');
850         } else if (PrefixSpaceChange[i] < 0 && AllowsSpaceChange) {
851           Prefix[i] = IndentPrefix
852                           .drop_back(std::min<std::size_t>(
853                               -PrefixSpaceChange[i], SpacesInPrefix))
854                           .str();
855         } else {
856           Prefix[i] = IndentPrefix.str();
857         }
858       } else {
859         // If the IndentPrefix is the whole line, there is no content and we
860         // drop just all space
861         Prefix[i] = IndentPrefix.drop_back(SpacesInPrefix).str();
862       }
863 
864       Tokens[i] = LineTok;
865       Content[i] = Lines[i].substr(IndentPrefix.size());
866       ContentColumn[i] =
867           StartColumn + encoding::columnWidthWithTabs(Prefix[i], StartColumn,
868                                                       Style.TabWidth, Encoding);
869 
870       // Calculate the end of the non-whitespace text in this line.
871       size_t EndOfLine = Content[i].find_last_not_of(Blanks);
872       if (EndOfLine == StringRef::npos)
873         EndOfLine = Content[i].size();
874       else
875         ++EndOfLine;
876       Content[i] = Content[i].substr(0, EndOfLine);
877     }
878     LineTok = CurrentTok->Next;
879     if (CurrentTok->Next && !CurrentTok->Next->ContinuesLineCommentSection) {
880       // A line comment section needs to broken by a line comment that is
881       // preceded by at least two newlines. Note that we put this break here
882       // instead of breaking at a previous stage during parsing, since that
883       // would split the contents of the enum into two unwrapped lines in this
884       // example, which is undesirable:
885       // enum A {
886       //   a, // comment about a
887       //
888       //   // comment about b
889       //   b
890       // };
891       //
892       // FIXME: Consider putting separate line comment sections as children to
893       // the unwrapped line instead.
894       break;
895     }
896   }
897 }
898 
899 unsigned
900 BreakableLineCommentSection::getRangeLength(unsigned LineIndex, unsigned Offset,
901                                             StringRef::size_type Length,
902                                             unsigned StartColumn) const {
903   return encoding::columnWidthWithTabs(
904       Content[LineIndex].substr(Offset, Length), StartColumn, Style.TabWidth,
905       Encoding);
906 }
907 
908 unsigned
909 BreakableLineCommentSection::getContentStartColumn(unsigned LineIndex,
910                                                    bool /*Break*/) const {
911   return ContentColumn[LineIndex];
912 }
913 
914 void BreakableLineCommentSection::insertBreak(
915     unsigned LineIndex, unsigned TailOffset, Split Split,
916     unsigned ContentIndent, WhitespaceManager &Whitespaces) const {
917   StringRef Text = Content[LineIndex].substr(TailOffset);
918   // Compute the offset of the split relative to the beginning of the token
919   // text.
920   unsigned BreakOffsetInToken =
921       Text.data() - tokenAt(LineIndex).TokenText.data() + Split.first;
922   unsigned CharsToRemove = Split.second;
923   Whitespaces.replaceWhitespaceInToken(
924       tokenAt(LineIndex), BreakOffsetInToken, CharsToRemove, "",
925       Prefix[LineIndex], InPPDirective, /*Newlines=*/1,
926       /*Spaces=*/ContentColumn[LineIndex] - Prefix[LineIndex].size());
927 }
928 
929 BreakableComment::Split BreakableLineCommentSection::getReflowSplit(
930     unsigned LineIndex, const llvm::Regex &CommentPragmasRegex) const {
931   if (!mayReflow(LineIndex, CommentPragmasRegex))
932     return Split(StringRef::npos, 0);
933 
934   size_t Trimmed = Content[LineIndex].find_first_not_of(Blanks);
935 
936   // In a line comment section each line is a separate token; thus, after a
937   // split we replace all whitespace before the current line comment token
938   // (which does not need to be included in the split), plus the start of the
939   // line up to where the content starts.
940   return Split(0, Trimmed != StringRef::npos ? Trimmed : 0);
941 }
942 
943 void BreakableLineCommentSection::reflow(unsigned LineIndex,
944                                          WhitespaceManager &Whitespaces) const {
945   if (LineIndex > 0 && Tokens[LineIndex] != Tokens[LineIndex - 1]) {
946     // Reflow happens between tokens. Replace the whitespace between the
947     // tokens by the empty string.
948     Whitespaces.replaceWhitespace(
949         *Tokens[LineIndex], /*Newlines=*/0, /*Spaces=*/0,
950         /*StartOfTokenColumn=*/StartColumn, /*IsAligned=*/true,
951         /*InPPDirective=*/false);
952   } else if (LineIndex > 0) {
953     // In case we're reflowing after the '\' in:
954     //
955     //   // line comment \
956     //   // line 2
957     //
958     // the reflow happens inside the single comment token (it is a single line
959     // comment with an unescaped newline).
960     // Replace the whitespace between the '\' and '//' with the empty string.
961     //
962     // Offset points to after the '\' relative to start of the token.
963     unsigned Offset = Lines[LineIndex - 1].data() +
964                       Lines[LineIndex - 1].size() -
965                       tokenAt(LineIndex - 1).TokenText.data();
966     // WhitespaceLength is the number of chars between the '\' and the '//' on
967     // the next line.
968     unsigned WhitespaceLength =
969         Lines[LineIndex].data() - tokenAt(LineIndex).TokenText.data() - Offset;
970     Whitespaces.replaceWhitespaceInToken(*Tokens[LineIndex], Offset,
971                                          /*ReplaceChars=*/WhitespaceLength,
972                                          /*PreviousPostfix=*/"",
973                                          /*CurrentPrefix=*/"",
974                                          /*InPPDirective=*/false,
975                                          /*Newlines=*/0,
976                                          /*Spaces=*/0);
977   }
978   // Replace the indent and prefix of the token with the reflow prefix.
979   unsigned Offset =
980       Lines[LineIndex].data() - tokenAt(LineIndex).TokenText.data();
981   unsigned WhitespaceLength =
982       Content[LineIndex].data() - Lines[LineIndex].data();
983   Whitespaces.replaceWhitespaceInToken(*Tokens[LineIndex], Offset,
984                                        /*ReplaceChars=*/WhitespaceLength,
985                                        /*PreviousPostfix=*/"",
986                                        /*CurrentPrefix=*/ReflowPrefix,
987                                        /*InPPDirective=*/false,
988                                        /*Newlines=*/0,
989                                        /*Spaces=*/0);
990 }
991 
992 void BreakableLineCommentSection::adaptStartOfLine(
993     unsigned LineIndex, WhitespaceManager &Whitespaces) const {
994   // If this is the first line of a token, we need to inform Whitespace Manager
995   // about it: either adapt the whitespace range preceding it, or mark it as an
996   // untouchable token.
997   // This happens for instance here:
998   // // line 1 \
999   // // line 2
1000   if (LineIndex > 0 && Tokens[LineIndex] != Tokens[LineIndex - 1]) {
1001     // This is the first line for the current token, but no reflow with the
1002     // previous token is necessary. However, we still may need to adjust the
1003     // start column. Note that ContentColumn[LineIndex] is the expected
1004     // content column after a possible update to the prefix, hence the prefix
1005     // length change is included.
1006     unsigned LineColumn =
1007         ContentColumn[LineIndex] -
1008         (Content[LineIndex].data() - Lines[LineIndex].data()) +
1009         (OriginalPrefix[LineIndex].size() - Prefix[LineIndex].size());
1010 
1011     // We always want to create a replacement instead of adding an untouchable
1012     // token, even if LineColumn is the same as the original column of the
1013     // token. This is because WhitespaceManager doesn't align trailing
1014     // comments if they are untouchable.
1015     Whitespaces.replaceWhitespace(*Tokens[LineIndex],
1016                                   /*Newlines=*/1,
1017                                   /*Spaces=*/LineColumn,
1018                                   /*StartOfTokenColumn=*/LineColumn,
1019                                   /*IsAligned=*/true,
1020                                   /*InPPDirective=*/false);
1021   }
1022   if (OriginalPrefix[LineIndex] != Prefix[LineIndex]) {
1023     // Adjust the prefix if necessary.
1024     const auto SpacesToRemove = -std::min(PrefixSpaceChange[LineIndex], 0);
1025     const auto SpacesToAdd = std::max(PrefixSpaceChange[LineIndex], 0);
1026     Whitespaces.replaceWhitespaceInToken(
1027         tokenAt(LineIndex), OriginalPrefix[LineIndex].size() - SpacesToRemove,
1028         /*ReplaceChars=*/SpacesToRemove, "", "", /*InPPDirective=*/false,
1029         /*Newlines=*/0, /*Spaces=*/SpacesToAdd);
1030   }
1031 }
1032 
1033 void BreakableLineCommentSection::updateNextToken(LineState &State) const {
1034   if (LastLineTok)
1035     State.NextToken = LastLineTok->Next;
1036 }
1037 
1038 bool BreakableLineCommentSection::mayReflow(
1039     unsigned LineIndex, const llvm::Regex &CommentPragmasRegex) const {
1040   // Line comments have the indent as part of the prefix, so we need to
1041   // recompute the start of the line.
1042   StringRef IndentContent = Content[LineIndex];
1043   if (Lines[LineIndex].startswith("//"))
1044     IndentContent = Lines[LineIndex].substr(2);
1045   // FIXME: Decide whether we want to reflow non-regular indents:
1046   // Currently, we only reflow when the OriginalPrefix[LineIndex] matches the
1047   // OriginalPrefix[LineIndex-1]. That means we don't reflow
1048   // // text that protrudes
1049   // //    into text with different indent
1050   // We do reflow in that case in block comments.
1051   return LineIndex > 0 && !CommentPragmasRegex.match(IndentContent) &&
1052          mayReflowContent(Content[LineIndex]) && !Tok.Finalized &&
1053          !switchesFormatting(tokenAt(LineIndex)) &&
1054          OriginalPrefix[LineIndex] == OriginalPrefix[LineIndex - 1];
1055 }
1056 
1057 } // namespace format
1058 } // namespace clang
1059