1 //===--- BreakableToken.cpp - Format C++ code -----------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
11 /// Contains implementation of BreakableToken class and classes derived
14 //===----------------------------------------------------------------------===//
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"
24 #define DEBUG_TYPE "format-token-breaker"
29 static const char *const Blanks = " \t\v\f\r";
30 static bool IsBlank(char C) {
43 static StringRef getLineCommentIndentPrefix(StringRef Comment,
44 const FormatStyle &Style) {
45 static const char *const KnownCStylePrefixes[] = {"///<", "//!<", "///", "//",
47 static const char *const KnownTextProtoPrefixes[] = {"//", "#", "##", "###",
49 ArrayRef<const char *> KnownPrefixes(KnownCStylePrefixes);
50 if (Style.Language == FormatStyle::LK_TextProto)
51 KnownPrefixes = KnownTextProtoPrefixes;
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] == ' ')
59 if (PrefixLength > LongestPrefix.size())
60 LongestPrefix = Comment.substr(0, PrefixLength);
66 static BreakableToken::Split getCommentSplit(StringRef Text,
67 unsigned ContentStartColumn,
70 encoding::Encoding Encoding) {
71 LLVM_DEBUG(llvm::dbgs() << "Comment split: \"" << Text << ", " << ColumnLimit
72 << "\", Content start: " << ContentStartColumn
74 if (ColumnLimit <= ContentStartColumn + 1)
75 return BreakableToken::Split(StringRef::npos, 0);
77 unsigned MaxSplit = ColumnLimit - ContentStartColumn + 1;
78 unsigned MaxSplitBytes = 0;
80 for (unsigned NumChars = 0;
81 NumChars < MaxSplit && MaxSplitBytes < Text.size();) {
82 unsigned BytesInChar =
83 encoding::getCodePointNumBytes(Text[MaxSplitBytes], Encoding);
85 encoding::columnWidthWithTabs(Text.substr(MaxSplitBytes, BytesInChar),
86 ContentStartColumn, TabWidth, Encoding);
87 MaxSplitBytes += BytesInChar;
90 StringRef::size_type SpaceOffset = Text.find_last_of(Blanks, MaxSplitBytes);
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);
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));
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());
117 return BreakableToken::Split(StringRef::npos, 0);
120 static BreakableToken::Split
121 getStringSplit(StringRef Text, unsigned UsedColumns, unsigned ColumnLimit,
122 unsigned TabWidth, encoding::Encoding Encoding) {
123 // FIXME: Reduce unit test case.
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;;) {
135 if (Text[0] == '\\') {
136 Advance = encoding::getEscapeSequenceLength(Text);
139 Advance = encoding::getCodePointNumBytes(Text[0], Encoding);
140 Chars += encoding::columnWidthWithTabs(
141 Text.substr(0, Advance), UsedColumns + Chars, TabWidth, Encoding);
144 if (Chars > MaxSplit || Text.size() <= Advance)
147 if (IsBlank(Text[0]))
148 SpaceOffset = SplitPoint;
150 SlashOffset = SplitPoint;
151 if (Advance == 1 && !isAlphanumeric(Text[0]))
152 WordStartOffset = SplitPoint;
154 SplitPoint += Advance;
155 Text = Text.substr(Advance);
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);
165 return BreakableToken::Split(SplitPoint, 0);
166 return BreakableToken::Split(StringRef::npos, 0);
169 bool switchesFormatting(const FormatToken &Token) {
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");
178 BreakableToken::getLengthAfterCompression(unsigned RemainingTokenColumns,
180 // Example: consider the content
182 // - RemainingTokenColumns is the original number of columns, 10;
183 // - Split is (4, 2), denoting the two spaces between the two words;
185 // We compute the number of columns when the split is compressed into a single
189 // FIXME: Correctly measure the length of whitespace in Split.second so it
191 return RemainingTokenColumns + 1 - Split.second;
194 unsigned BreakableStringLiteral::getLineCount() const { return 1; }
196 unsigned BreakableStringLiteral::getRangeLength(unsigned LineIndex,
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.");
205 BreakableStringLiteral::getRemainingLength(unsigned LineIndex, unsigned Offset,
206 unsigned StartColumn) const {
207 return UnbreakableTailLength + Postfix.size() +
208 encoding::columnWidthWithTabs(Line.substr(Offset, StringRef::npos),
209 StartColumn, Style.TabWidth, Encoding);
212 unsigned BreakableStringLiteral::getContentStartColumn(unsigned LineIndex,
214 return StartColumn + Prefix.size();
217 BreakableStringLiteral::BreakableStringLiteral(
218 const FormatToken &Tok, unsigned StartColumn, StringRef Prefix,
219 StringRef Postfix, unsigned UnbreakableTailLength, bool InPPDirective,
220 encoding::Encoding Encoding, const FormatStyle &Style)
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());
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);
236 void BreakableStringLiteral::insertBreak(unsigned LineIndex,
237 unsigned TailOffset, Split Split,
238 WhitespaceManager &Whitespaces) const {
239 Whitespaces.replaceWhitespaceInToken(
240 Tok, Prefix.size() + TailOffset + Split.first, Split.second, Postfix,
241 Prefix, InPPDirective, 1, StartColumn);
244 BreakableComment::BreakableComment(const FormatToken &Token,
245 unsigned StartColumn, bool InPPDirective,
246 encoding::Encoding Encoding,
247 const FormatStyle &Style)
248 : BreakableToken(Token, InPPDirective, Encoding, Style),
249 StartColumn(StartColumn) {}
251 unsigned BreakableComment::getLineCount() const { return Lines.size(); }
253 BreakableToken::Split
254 BreakableComment::getSplit(unsigned LineIndex, unsigned TailOffset,
255 unsigned ColumnLimit, unsigned ContentStartColumn,
256 llvm::Regex &CommentPragmasRegex) const {
257 // Don't break lines matching the comment pragmas regex.
258 if (CommentPragmasRegex.match(Content[LineIndex]))
259 return Split(StringRef::npos, 0);
260 return getCommentSplit(Content[LineIndex].substr(TailOffset),
261 ContentStartColumn, ColumnLimit, Style.TabWidth,
265 void BreakableComment::compressWhitespace(
266 unsigned LineIndex, unsigned TailOffset, Split Split,
267 WhitespaceManager &Whitespaces) const {
268 StringRef Text = Content[LineIndex].substr(TailOffset);
269 // Text is relative to the content line, but Whitespaces operates relative to
270 // the start of the corresponding token, so compute the start of the Split
271 // that needs to be compressed into a single space relative to the start of
273 unsigned BreakOffsetInToken =
274 Text.data() - tokenAt(LineIndex).TokenText.data() + Split.first;
275 unsigned CharsToRemove = Split.second;
276 Whitespaces.replaceWhitespaceInToken(
277 tokenAt(LineIndex), BreakOffsetInToken, CharsToRemove, "", "",
278 /*InPPDirective=*/false, /*Newlines=*/0, /*Spaces=*/1);
281 const FormatToken &BreakableComment::tokenAt(unsigned LineIndex) const {
282 return Tokens[LineIndex] ? *Tokens[LineIndex] : Tok;
285 static bool mayReflowContent(StringRef Content) {
286 Content = Content.trim(Blanks);
287 // Lines starting with '@' commonly have special meaning.
288 // Lines starting with '-', '-#', '+' or '*' are bulleted/numbered lists.
289 bool hasSpecialMeaningPrefix = false;
290 for (StringRef Prefix :
291 {"@", "TODO", "FIXME", "XXX", "-# ", "- ", "+ ", "* "}) {
292 if (Content.startswith(Prefix)) {
293 hasSpecialMeaningPrefix = true;
298 // Numbered lists may also start with a number followed by '.'
299 // To avoid issues if a line starts with a number which is actually the end
300 // of a previous line, we only consider numbers with up to 2 digits.
301 static auto *const kNumberedListRegexp = new llvm::Regex("^[1-9][0-9]?\\. ");
302 hasSpecialMeaningPrefix =
303 hasSpecialMeaningPrefix || kNumberedListRegexp->match(Content);
305 // Simple heuristic for what to reflow: content should contain at least two
306 // characters and either the first or second character must be
308 return Content.size() >= 2 && !hasSpecialMeaningPrefix &&
309 !Content.endswith("\\") &&
310 // Note that this is UTF-8 safe, since if isPunctuation(Content[0]) is
311 // true, then the first code point must be 1 byte long.
312 (!isPunctuation(Content[0]) || !isPunctuation(Content[1]));
315 BreakableBlockComment::BreakableBlockComment(
316 const FormatToken &Token, unsigned StartColumn,
317 unsigned OriginalStartColumn, bool FirstInLine, bool InPPDirective,
318 encoding::Encoding Encoding, const FormatStyle &Style)
319 : BreakableComment(Token, StartColumn, InPPDirective, Encoding, Style),
320 DelimitersOnNewline(false),
321 UnbreakableTailLength(Token.UnbreakableTailLength) {
322 assert(Tok.is(TT_BlockComment) &&
323 "block comment section must start with a block comment");
325 StringRef TokenText(Tok.TokenText);
326 assert(TokenText.startswith("/*") && TokenText.endswith("*/"));
327 TokenText.substr(2, TokenText.size() - 4).split(Lines, "\n");
329 int IndentDelta = StartColumn - OriginalStartColumn;
330 Content.resize(Lines.size());
331 Content[0] = Lines[0];
332 ContentColumn.resize(Lines.size());
333 // Account for the initial '/*'.
334 ContentColumn[0] = StartColumn + 2;
335 Tokens.resize(Lines.size());
336 for (size_t i = 1; i < Lines.size(); ++i)
337 adjustWhitespace(i, IndentDelta);
339 // Align decorations with the column of the star on the first line,
340 // that is one column after the start "/*".
341 DecorationColumn = StartColumn + 1;
343 // Account for comment decoration patterns like this:
348 if (Lines.size() >= 2 && Content[1].startswith("**") &&
349 static_cast<unsigned>(ContentColumn[1]) == StartColumn) {
350 DecorationColumn = StartColumn;
354 if (Lines.size() == 1 && !FirstInLine) {
355 // Comments for which FirstInLine is false can start on arbitrary column,
356 // and available horizontal space can be too small to align consecutive
357 // lines with the first one.
358 // FIXME: We could, probably, align them to current indentation level, but
359 // now we just wrap them without stars.
362 for (size_t i = 1, e = Lines.size(); i < e && !Decoration.empty(); ++i) {
363 // If the last line is empty, the closing "*/" will have a star.
364 if (i + 1 == e && Content[i].empty())
366 if (!Content[i].empty() && i + 1 != e && Decoration.startswith(Content[i]))
368 while (!Content[i].startswith(Decoration))
369 Decoration = Decoration.substr(0, Decoration.size() - 1);
372 LastLineNeedsDecoration = true;
373 IndentAtLineBreak = ContentColumn[0] + 1;
374 for (size_t i = 1, e = Lines.size(); i < e; ++i) {
375 if (Content[i].empty()) {
377 // Empty last line means that we already have a star as a part of the
378 // trailing */. We also need to preserve whitespace, so that */ is
379 // correctly indented.
380 LastLineNeedsDecoration = false;
381 // Align the star in the last '*/' with the stars on the previous lines.
382 if (e >= 2 && !Decoration.empty()) {
383 ContentColumn[i] = DecorationColumn;
385 } else if (Decoration.empty()) {
386 // For all other lines, set the start column to 0 if they're empty, so
387 // we do not insert trailing whitespace anywhere.
388 ContentColumn[i] = 0;
393 // The first line already excludes the star.
394 // The last line excludes the star if LastLineNeedsDecoration is false.
395 // For all other lines, adjust the line to exclude the star and
396 // (optionally) the first whitespace.
397 unsigned DecorationSize = Decoration.startswith(Content[i])
400 if (DecorationSize) {
401 ContentColumn[i] = DecorationColumn + DecorationSize;
403 Content[i] = Content[i].substr(DecorationSize);
404 if (!Decoration.startswith(Content[i]))
406 std::min<int>(IndentAtLineBreak, std::max(0, ContentColumn[i]));
408 IndentAtLineBreak = std::max<unsigned>(IndentAtLineBreak, Decoration.size());
410 // Detect a multiline jsdoc comment and set DelimitersOnNewline in that case.
411 if (Style.Language == FormatStyle::LK_JavaScript ||
412 Style.Language == FormatStyle::LK_Java) {
413 if ((Lines[0] == "*" || Lines[0].startswith("* ")) && Lines.size() > 1) {
414 // This is a multiline jsdoc comment.
415 DelimitersOnNewline = true;
416 } else if (Lines[0].startswith("* ") && Lines.size() == 1) {
417 // Detect a long single-line comment, like:
418 // /** long long long */
419 // Below, '2' is the width of '*/'.
422 encoding::columnWidthWithTabs(Lines[0], ContentColumn[0],
423 Style.TabWidth, Encoding) +
425 DelimitersOnNewline = EndColumn > Style.ColumnLimit;
430 llvm::dbgs() << "IndentAtLineBreak " << IndentAtLineBreak << "\n";
431 llvm::dbgs() << "DelimitersOnNewline " << DelimitersOnNewline << "\n";
432 for (size_t i = 0; i < Lines.size(); ++i) {
433 llvm::dbgs() << i << " |" << Content[i] << "| "
434 << "CC=" << ContentColumn[i] << "| "
435 << "IN=" << (Content[i].data() - Lines[i].data()) << "\n";
440 void BreakableBlockComment::adjustWhitespace(unsigned LineIndex,
442 // When in a preprocessor directive, the trailing backslash in a block comment
443 // is not needed, but can serve a purpose of uniformity with necessary escaped
444 // newlines outside the comment. In this case we remove it here before
445 // trimming the trailing whitespace. The backslash will be re-added later when
446 // inserting a line break.
447 size_t EndOfPreviousLine = Lines[LineIndex - 1].size();
448 if (InPPDirective && Lines[LineIndex - 1].endswith("\\"))
451 // Calculate the end of the non-whitespace text in the previous line.
453 Lines[LineIndex - 1].find_last_not_of(Blanks, EndOfPreviousLine);
454 if (EndOfPreviousLine == StringRef::npos)
455 EndOfPreviousLine = 0;
458 // Calculate the start of the non-whitespace text in the current line.
459 size_t StartOfLine = Lines[LineIndex].find_first_not_of(Blanks);
460 if (StartOfLine == StringRef::npos)
461 StartOfLine = Lines[LineIndex].rtrim("\r\n").size();
463 StringRef Whitespace = Lines[LineIndex].substr(0, StartOfLine);
464 // Adjust Lines to only contain relevant text.
465 size_t PreviousContentOffset =
466 Content[LineIndex - 1].data() - Lines[LineIndex - 1].data();
467 Content[LineIndex - 1] = Lines[LineIndex - 1].substr(
468 PreviousContentOffset, EndOfPreviousLine - PreviousContentOffset);
469 Content[LineIndex] = Lines[LineIndex].substr(StartOfLine);
471 // Adjust the start column uniformly across all lines.
472 ContentColumn[LineIndex] =
473 encoding::columnWidthWithTabs(Whitespace, 0, Style.TabWidth, Encoding) +
477 unsigned BreakableBlockComment::getRangeLength(unsigned LineIndex,
479 StringRef::size_type Length,
480 unsigned StartColumn) const {
481 unsigned LineLength =
482 encoding::columnWidthWithTabs(Content[LineIndex].substr(Offset, Length),
483 StartColumn, Style.TabWidth, Encoding);
484 // FIXME: This should go into getRemainingLength instead, but we currently
485 // break tests when putting it there. Investigate how to fix those tests.
486 // The last line gets a "*/" postfix.
487 if (LineIndex + 1 == Lines.size()) {
489 // We never need a decoration when breaking just the trailing "*/" postfix.
490 // Note that checking that Length == 0 is not enough, since Length could
491 // also be StringRef::npos.
492 if (Content[LineIndex].substr(Offset, StringRef::npos).empty()) {
493 LineLength -= Decoration.size();
499 unsigned BreakableBlockComment::getRemainingLength(unsigned LineIndex,
501 unsigned StartColumn) const {
502 return UnbreakableTailLength +
503 getRangeLength(LineIndex, Offset, StringRef::npos, StartColumn);
506 unsigned BreakableBlockComment::getContentStartColumn(unsigned LineIndex,
509 return IndentAtLineBreak;
510 return std::max(0, ContentColumn[LineIndex]);
513 void BreakableBlockComment::insertBreak(unsigned LineIndex, unsigned TailOffset,
515 WhitespaceManager &Whitespaces) const {
516 StringRef Text = Content[LineIndex].substr(TailOffset);
517 StringRef Prefix = Decoration;
518 // We need this to account for the case when we have a decoration "* " for all
519 // the lines except for the last one, where the star in "*/" acts as a
521 unsigned LocalIndentAtLineBreak = IndentAtLineBreak;
522 if (LineIndex + 1 == Lines.size() &&
523 Text.size() == Split.first + Split.second) {
524 // For the last line we need to break before "*/", but not to add "* ".
526 if (LocalIndentAtLineBreak >= 2)
527 LocalIndentAtLineBreak -= 2;
529 // The split offset is from the beginning of the line. Convert it to an offset
530 // from the beginning of the token text.
531 unsigned BreakOffsetInToken =
532 Text.data() - tokenAt(LineIndex).TokenText.data() + Split.first;
533 unsigned CharsToRemove = Split.second;
534 assert(LocalIndentAtLineBreak >= Prefix.size());
535 Whitespaces.replaceWhitespaceInToken(
536 tokenAt(LineIndex), BreakOffsetInToken, CharsToRemove, "", Prefix,
537 InPPDirective, /*Newlines=*/1,
538 /*Spaces=*/LocalIndentAtLineBreak - Prefix.size());
541 BreakableToken::Split
542 BreakableBlockComment::getReflowSplit(unsigned LineIndex,
543 llvm::Regex &CommentPragmasRegex) const {
544 if (!mayReflow(LineIndex, CommentPragmasRegex))
545 return Split(StringRef::npos, 0);
547 size_t Trimmed = Content[LineIndex].find_first_not_of(Blanks);
548 return Split(0, Trimmed != StringRef::npos ? Trimmed : 0);
551 bool BreakableBlockComment::introducesBreakBeforeToken() const {
552 // A break is introduced when we want delimiters on newline.
553 return DelimitersOnNewline &&
554 Lines[0].substr(1).find_first_not_of(Blanks) != StringRef::npos;
557 void BreakableBlockComment::reflow(unsigned LineIndex,
558 WhitespaceManager &Whitespaces) const {
559 StringRef TrimmedContent = Content[LineIndex].ltrim(Blanks);
560 // Here we need to reflow.
561 assert(Tokens[LineIndex - 1] == Tokens[LineIndex] &&
562 "Reflowing whitespace within a token");
563 // This is the offset of the end of the last line relative to the start of
564 // the token text in the token.
565 unsigned WhitespaceOffsetInToken = Content[LineIndex - 1].data() +
566 Content[LineIndex - 1].size() -
567 tokenAt(LineIndex).TokenText.data();
568 unsigned WhitespaceLength = TrimmedContent.data() -
569 tokenAt(LineIndex).TokenText.data() -
570 WhitespaceOffsetInToken;
571 Whitespaces.replaceWhitespaceInToken(
572 tokenAt(LineIndex), WhitespaceOffsetInToken,
573 /*ReplaceChars=*/WhitespaceLength, /*PreviousPostfix=*/"",
574 /*CurrentPrefix=*/ReflowPrefix, InPPDirective, /*Newlines=*/0,
578 void BreakableBlockComment::adaptStartOfLine(
579 unsigned LineIndex, WhitespaceManager &Whitespaces) const {
580 if (LineIndex == 0) {
581 if (DelimitersOnNewline) {
582 // Since we're breaking at index 1 below, the break position and the
583 // break length are the same.
584 size_t BreakLength = Lines[0].substr(1).find_first_not_of(Blanks);
585 if (BreakLength != StringRef::npos)
586 insertBreak(LineIndex, 0, Split(1, BreakLength), Whitespaces);
590 // Here no reflow with the previous line will happen.
591 // Fix the decoration of the line at LineIndex.
592 StringRef Prefix = Decoration;
593 if (Content[LineIndex].empty()) {
594 if (LineIndex + 1 == Lines.size()) {
595 if (!LastLineNeedsDecoration) {
596 // If the last line was empty, we don't need a prefix, as the */ will
597 // line up with the decoration (if it exists).
600 } else if (!Decoration.empty()) {
601 // For other empty lines, if we do have a decoration, adapt it to not
602 // contain a trailing whitespace.
603 Prefix = Prefix.substr(0, 1);
606 if (ContentColumn[LineIndex] == 1) {
607 // This line starts immediately after the decorating *.
608 Prefix = Prefix.substr(0, 1);
611 // This is the offset of the end of the last line relative to the start of the
612 // token text in the token.
613 unsigned WhitespaceOffsetInToken = Content[LineIndex - 1].data() +
614 Content[LineIndex - 1].size() -
615 tokenAt(LineIndex).TokenText.data();
616 unsigned WhitespaceLength = Content[LineIndex].data() -
617 tokenAt(LineIndex).TokenText.data() -
618 WhitespaceOffsetInToken;
619 Whitespaces.replaceWhitespaceInToken(
620 tokenAt(LineIndex), WhitespaceOffsetInToken, WhitespaceLength, "", Prefix,
621 InPPDirective, /*Newlines=*/1, ContentColumn[LineIndex] - Prefix.size());
624 BreakableToken::Split
625 BreakableBlockComment::getSplitAfterLastLine(unsigned TailOffset) const {
626 if (DelimitersOnNewline) {
627 // Replace the trailing whitespace of the last line with a newline.
628 // In case the last line is empty, the ending '*/' is already on its own
630 StringRef Line = Content.back().substr(TailOffset);
631 StringRef TrimmedLine = Line.rtrim(Blanks);
632 if (!TrimmedLine.empty())
633 return Split(TrimmedLine.size(), Line.size() - TrimmedLine.size());
635 return Split(StringRef::npos, 0);
638 bool BreakableBlockComment::mayReflow(unsigned LineIndex,
639 llvm::Regex &CommentPragmasRegex) const {
640 // Content[LineIndex] may exclude the indent after the '*' decoration. In that
641 // case, we compute the start of the comment pragma manually.
642 StringRef IndentContent = Content[LineIndex];
643 if (Lines[LineIndex].ltrim(Blanks).startswith("*")) {
644 IndentContent = Lines[LineIndex].ltrim(Blanks).substr(1);
646 return LineIndex > 0 && !CommentPragmasRegex.match(IndentContent) &&
647 mayReflowContent(Content[LineIndex]) && !Tok.Finalized &&
648 !switchesFormatting(tokenAt(LineIndex));
651 BreakableLineCommentSection::BreakableLineCommentSection(
652 const FormatToken &Token, unsigned StartColumn,
653 unsigned OriginalStartColumn, bool FirstInLine, bool InPPDirective,
654 encoding::Encoding Encoding, const FormatStyle &Style)
655 : BreakableComment(Token, StartColumn, InPPDirective, Encoding, Style) {
656 assert(Tok.is(TT_LineComment) &&
657 "line comment section must start with a line comment");
658 FormatToken *LineTok = nullptr;
659 for (const FormatToken *CurrentTok = &Tok;
660 CurrentTok && CurrentTok->is(TT_LineComment);
661 CurrentTok = CurrentTok->Next) {
662 LastLineTok = LineTok;
663 StringRef TokenText(CurrentTok->TokenText);
664 assert((TokenText.startswith("//") || TokenText.startswith("#")) &&
665 "unsupported line comment prefix, '//' and '#' are supported");
666 size_t FirstLineIndex = Lines.size();
667 TokenText.split(Lines, "\n");
668 Content.resize(Lines.size());
669 ContentColumn.resize(Lines.size());
670 OriginalContentColumn.resize(Lines.size());
671 Tokens.resize(Lines.size());
672 Prefix.resize(Lines.size());
673 OriginalPrefix.resize(Lines.size());
674 for (size_t i = FirstLineIndex, e = Lines.size(); i < e; ++i) {
675 Lines[i] = Lines[i].ltrim(Blanks);
676 // We need to trim the blanks in case this is not the first line in a
677 // multiline comment. Then the indent is included in Lines[i].
678 StringRef IndentPrefix =
679 getLineCommentIndentPrefix(Lines[i].ltrim(Blanks), Style);
680 assert((TokenText.startswith("//") || TokenText.startswith("#")) &&
681 "unsupported line comment prefix, '//' and '#' are supported");
682 OriginalPrefix[i] = Prefix[i] = IndentPrefix;
683 if (Lines[i].size() > Prefix[i].size() &&
684 isAlphanumeric(Lines[i][Prefix[i].size()])) {
685 if (Prefix[i] == "//")
687 else if (Prefix[i] == "///")
689 else if (Prefix[i] == "//!")
691 else if (Prefix[i] == "///<")
693 else if (Prefix[i] == "//!<")
695 else if (Prefix[i] == "#" &&
696 Style.Language == FormatStyle::LK_TextProto)
701 Content[i] = Lines[i].substr(IndentPrefix.size());
702 OriginalContentColumn[i] =
703 StartColumn + encoding::columnWidthWithTabs(OriginalPrefix[i],
705 Style.TabWidth, Encoding);
707 StartColumn + encoding::columnWidthWithTabs(Prefix[i], StartColumn,
708 Style.TabWidth, Encoding);
710 // Calculate the end of the non-whitespace text in this line.
711 size_t EndOfLine = Content[i].find_last_not_of(Blanks);
712 if (EndOfLine == StringRef::npos)
713 EndOfLine = Content[i].size();
716 Content[i] = Content[i].substr(0, EndOfLine);
718 LineTok = CurrentTok->Next;
719 if (CurrentTok->Next && !CurrentTok->Next->ContinuesLineCommentSection) {
720 // A line comment section needs to broken by a line comment that is
721 // preceded by at least two newlines. Note that we put this break here
722 // instead of breaking at a previous stage during parsing, since that
723 // would split the contents of the enum into two unwrapped lines in this
724 // example, which is undesirable:
726 // a, // comment about a
728 // // comment about b
732 // FIXME: Consider putting separate line comment sections as children to
733 // the unwrapped line instead.
740 BreakableLineCommentSection::getRangeLength(unsigned LineIndex, unsigned Offset,
741 StringRef::size_type Length,
742 unsigned StartColumn) const {
743 return encoding::columnWidthWithTabs(
744 Content[LineIndex].substr(Offset, Length), StartColumn, Style.TabWidth,
748 unsigned BreakableLineCommentSection::getContentStartColumn(unsigned LineIndex,
751 return OriginalContentColumn[LineIndex];
752 return ContentColumn[LineIndex];
755 void BreakableLineCommentSection::insertBreak(
756 unsigned LineIndex, unsigned TailOffset, Split Split,
757 WhitespaceManager &Whitespaces) const {
758 StringRef Text = Content[LineIndex].substr(TailOffset);
759 // Compute the offset of the split relative to the beginning of the token
761 unsigned BreakOffsetInToken =
762 Text.data() - tokenAt(LineIndex).TokenText.data() + Split.first;
763 unsigned CharsToRemove = Split.second;
764 // Compute the size of the new indent, including the size of the new prefix of
765 // the newly broken line.
766 unsigned IndentAtLineBreak = OriginalContentColumn[LineIndex] +
767 Prefix[LineIndex].size() -
768 OriginalPrefix[LineIndex].size();
769 assert(IndentAtLineBreak >= Prefix[LineIndex].size());
770 Whitespaces.replaceWhitespaceInToken(
771 tokenAt(LineIndex), BreakOffsetInToken, CharsToRemove, "",
772 Prefix[LineIndex], InPPDirective, /*Newlines=*/1,
773 /*Spaces=*/IndentAtLineBreak - Prefix[LineIndex].size());
776 BreakableComment::Split BreakableLineCommentSection::getReflowSplit(
777 unsigned LineIndex, llvm::Regex &CommentPragmasRegex) const {
778 if (!mayReflow(LineIndex, CommentPragmasRegex))
779 return Split(StringRef::npos, 0);
781 size_t Trimmed = Content[LineIndex].find_first_not_of(Blanks);
783 // In a line comment section each line is a separate token; thus, after a
784 // split we replace all whitespace before the current line comment token
785 // (which does not need to be included in the split), plus the start of the
786 // line up to where the content starts.
787 return Split(0, Trimmed != StringRef::npos ? Trimmed : 0);
790 void BreakableLineCommentSection::reflow(unsigned LineIndex,
791 WhitespaceManager &Whitespaces) const {
792 if (LineIndex > 0 && Tokens[LineIndex] != Tokens[LineIndex - 1]) {
793 // Reflow happens between tokens. Replace the whitespace between the
794 // tokens by the empty string.
795 Whitespaces.replaceWhitespace(
796 *Tokens[LineIndex], /*Newlines=*/0, /*Spaces=*/0,
797 /*StartOfTokenColumn=*/StartColumn, /*InPPDirective=*/false);
798 } else if (LineIndex > 0) {
799 // In case we're reflowing after the '\' in:
804 // the reflow happens inside the single comment token (it is a single line
805 // comment with an unescaped newline).
806 // Replace the whitespace between the '\' and '//' with the empty string.
808 // Offset points to after the '\' relative to start of the token.
809 unsigned Offset = Lines[LineIndex - 1].data() +
810 Lines[LineIndex - 1].size() -
811 tokenAt(LineIndex - 1).TokenText.data();
812 // WhitespaceLength is the number of chars between the '\' and the '//' on
814 unsigned WhitespaceLength =
815 Lines[LineIndex].data() - tokenAt(LineIndex).TokenText.data() - Offset;
816 Whitespaces.replaceWhitespaceInToken(*Tokens[LineIndex],
818 /*ReplaceChars=*/WhitespaceLength,
819 /*PreviousPostfix=*/"",
820 /*CurrentPrefix=*/"",
821 /*InPPDirective=*/false,
826 // Replace the indent and prefix of the token with the reflow prefix.
828 Lines[LineIndex].data() - tokenAt(LineIndex).TokenText.data();
829 unsigned WhitespaceLength =
830 Content[LineIndex].data() - Lines[LineIndex].data();
831 Whitespaces.replaceWhitespaceInToken(*Tokens[LineIndex],
833 /*ReplaceChars=*/WhitespaceLength,
834 /*PreviousPostfix=*/"",
835 /*CurrentPrefix=*/ReflowPrefix,
836 /*InPPDirective=*/false,
841 void BreakableLineCommentSection::adaptStartOfLine(
842 unsigned LineIndex, WhitespaceManager &Whitespaces) const {
843 // If this is the first line of a token, we need to inform Whitespace Manager
844 // about it: either adapt the whitespace range preceding it, or mark it as an
845 // untouchable token.
846 // This happens for instance here:
849 if (LineIndex > 0 && Tokens[LineIndex] != Tokens[LineIndex - 1]) {
850 // This is the first line for the current token, but no reflow with the
851 // previous token is necessary. However, we still may need to adjust the
852 // start column. Note that ContentColumn[LineIndex] is the expected
853 // content column after a possible update to the prefix, hence the prefix
854 // length change is included.
855 unsigned LineColumn =
856 ContentColumn[LineIndex] -
857 (Content[LineIndex].data() - Lines[LineIndex].data()) +
858 (OriginalPrefix[LineIndex].size() - Prefix[LineIndex].size());
860 // We always want to create a replacement instead of adding an untouchable
861 // token, even if LineColumn is the same as the original column of the
862 // token. This is because WhitespaceManager doesn't align trailing
863 // comments if they are untouchable.
864 Whitespaces.replaceWhitespace(*Tokens[LineIndex],
866 /*Spaces=*/LineColumn,
867 /*StartOfTokenColumn=*/LineColumn,
868 /*InPPDirective=*/false);
870 if (OriginalPrefix[LineIndex] != Prefix[LineIndex]) {
871 // Adjust the prefix if necessary.
873 // Take care of the space possibly introduced after a decoration.
874 assert(Prefix[LineIndex] == (OriginalPrefix[LineIndex] + " ").str() &&
875 "Expecting a line comment prefix to differ from original by at most "
877 Whitespaces.replaceWhitespaceInToken(
878 tokenAt(LineIndex), OriginalPrefix[LineIndex].size(), 0, "", "",
879 /*InPPDirective=*/false, /*Newlines=*/0, /*Spaces=*/1);
883 void BreakableLineCommentSection::updateNextToken(LineState &State) const {
885 State.NextToken = LastLineTok->Next;
889 bool BreakableLineCommentSection::mayReflow(
890 unsigned LineIndex, llvm::Regex &CommentPragmasRegex) const {
891 // Line comments have the indent as part of the prefix, so we need to
892 // recompute the start of the line.
893 StringRef IndentContent = Content[LineIndex];
894 if (Lines[LineIndex].startswith("//")) {
895 IndentContent = Lines[LineIndex].substr(2);
897 // FIXME: Decide whether we want to reflow non-regular indents:
898 // Currently, we only reflow when the OriginalPrefix[LineIndex] matches the
899 // OriginalPrefix[LineIndex-1]. That means we don't reflow
900 // // text that protrudes
901 // // into text with different indent
902 // We do reflow in that case in block comments.
903 return LineIndex > 0 && !CommentPragmasRegex.match(IndentContent) &&
904 mayReflowContent(Content[LineIndex]) && !Tok.Finalized &&
905 !switchesFormatting(tokenAt(LineIndex)) &&
906 OriginalPrefix[LineIndex] == OriginalPrefix[LineIndex - 1];
909 } // namespace format