1 //===--- UnwrappedLineFormatter.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 #include "UnwrappedLineFormatter.h"
10 #include "FormatToken.h"
11 #include "NamespaceEndCommentsFixer.h"
12 #include "WhitespaceManager.h"
13 #include "llvm/Support/Debug.h"
14 #include <queue>
15
16 #define DEBUG_TYPE "format-formatter"
17
18 namespace clang {
19 namespace format {
20
21 namespace {
22
startsExternCBlock(const AnnotatedLine & Line)23 bool startsExternCBlock(const AnnotatedLine &Line) {
24 const FormatToken *Next = Line.First->getNextNonComment();
25 const FormatToken *NextNext = Next ? Next->getNextNonComment() : nullptr;
26 return Line.startsWith(tok::kw_extern) && Next && Next->isStringLiteral() &&
27 NextNext && NextNext->is(tok::l_brace);
28 }
29
isRecordLBrace(const FormatToken & Tok)30 bool isRecordLBrace(const FormatToken &Tok) {
31 return Tok.isOneOf(TT_ClassLBrace, TT_EnumLBrace, TT_RecordLBrace,
32 TT_StructLBrace, TT_UnionLBrace);
33 }
34
35 /// Tracks the indent level of \c AnnotatedLines across levels.
36 ///
37 /// \c nextLine must be called for each \c AnnotatedLine, after which \c
38 /// getIndent() will return the indent for the last line \c nextLine was called
39 /// with.
40 /// If the line is not formatted (and thus the indent does not change), calling
41 /// \c adjustToUnmodifiedLine after the call to \c nextLine will cause
42 /// subsequent lines on the same level to be indented at the same level as the
43 /// given line.
44 class LevelIndentTracker {
45 public:
LevelIndentTracker(const FormatStyle & Style,const AdditionalKeywords & Keywords,unsigned StartLevel,int AdditionalIndent)46 LevelIndentTracker(const FormatStyle &Style,
47 const AdditionalKeywords &Keywords, unsigned StartLevel,
48 int AdditionalIndent)
49 : Style(Style), Keywords(Keywords), AdditionalIndent(AdditionalIndent) {
50 for (unsigned i = 0; i != StartLevel; ++i)
51 IndentForLevel.push_back(Style.IndentWidth * i + AdditionalIndent);
52 }
53
54 /// Returns the indent for the current line.
getIndent() const55 unsigned getIndent() const { return Indent; }
56
57 /// Update the indent state given that \p Line is going to be formatted
58 /// next.
nextLine(const AnnotatedLine & Line)59 void nextLine(const AnnotatedLine &Line) {
60 Offset = getIndentOffset(*Line.First);
61 // Update the indent level cache size so that we can rely on it
62 // having the right size in adjustToUnmodifiedline.
63 if (Line.Level >= IndentForLevel.size())
64 IndentForLevel.resize(Line.Level + 1, -1);
65 if (Style.IndentPPDirectives != FormatStyle::PPDIS_None &&
66 (Line.InPPDirective ||
67 (Style.IndentPPDirectives == FormatStyle::PPDIS_BeforeHash &&
68 Line.Type == LT_CommentAbovePPDirective))) {
69 unsigned PPIndentWidth =
70 (Style.PPIndentWidth >= 0) ? Style.PPIndentWidth : Style.IndentWidth;
71 Indent = Line.InMacroBody
72 ? Line.PPLevel * PPIndentWidth +
73 (Line.Level - Line.PPLevel) * Style.IndentWidth
74 : Line.Level * PPIndentWidth;
75 Indent += AdditionalIndent;
76 } else {
77 // When going to lower levels, forget previous higher levels so that we
78 // recompute future higher levels. But don't forget them if we enter a PP
79 // directive, since these do not terminate a C++ code block.
80 if (!Line.InPPDirective) {
81 assert(Line.Level <= IndentForLevel.size());
82 IndentForLevel.resize(Line.Level + 1);
83 }
84 Indent = getIndent(Line.Level);
85 }
86 if (static_cast<int>(Indent) + Offset >= 0)
87 Indent += Offset;
88 if (Line.IsContinuation)
89 Indent = Line.Level * Style.IndentWidth + Style.ContinuationIndentWidth;
90 }
91
92 /// Update the level indent to adapt to the given \p Line.
93 ///
94 /// When a line is not formatted, we move the subsequent lines on the same
95 /// level to the same indent.
96 /// Note that \c nextLine must have been called before this method.
adjustToUnmodifiedLine(const AnnotatedLine & Line)97 void adjustToUnmodifiedLine(const AnnotatedLine &Line) {
98 if (Line.InPPDirective || Line.IsContinuation)
99 return;
100 assert(Line.Level < IndentForLevel.size());
101 if (Line.First->is(tok::comment) && IndentForLevel[Line.Level] != -1)
102 return;
103 unsigned LevelIndent = Line.First->OriginalColumn;
104 if (static_cast<int>(LevelIndent) - Offset >= 0)
105 LevelIndent -= Offset;
106 IndentForLevel[Line.Level] = LevelIndent;
107 }
108
109 private:
110 /// Get the offset of the line relatively to the level.
111 ///
112 /// For example, 'public:' labels in classes are offset by 1 or 2
113 /// characters to the left from their level.
getIndentOffset(const FormatToken & RootToken)114 int getIndentOffset(const FormatToken &RootToken) {
115 if (Style.Language == FormatStyle::LK_Java || Style.isJavaScript() ||
116 Style.isCSharp()) {
117 return 0;
118 }
119
120 auto IsAccessModifier = [this, &RootToken]() {
121 if (RootToken.isAccessSpecifier(Style.isCpp())) {
122 return true;
123 } else if (RootToken.isObjCAccessSpecifier()) {
124 return true;
125 }
126 // Handle Qt signals.
127 else if (RootToken.isOneOf(Keywords.kw_signals, Keywords.kw_qsignals) &&
128 RootToken.Next && RootToken.Next->is(tok::colon)) {
129 return true;
130 } else if (RootToken.Next &&
131 RootToken.Next->isOneOf(Keywords.kw_slots,
132 Keywords.kw_qslots) &&
133 RootToken.Next->Next && RootToken.Next->Next->is(tok::colon)) {
134 return true;
135 }
136 // Handle malformed access specifier e.g. 'private' without trailing ':'.
137 else if (!RootToken.Next && RootToken.isAccessSpecifier(false)) {
138 return true;
139 }
140 return false;
141 };
142
143 if (IsAccessModifier()) {
144 // The AccessModifierOffset may be overridden by IndentAccessModifiers,
145 // in which case we take a negative value of the IndentWidth to simulate
146 // the upper indent level.
147 return Style.IndentAccessModifiers ? -Style.IndentWidth
148 : Style.AccessModifierOffset;
149 }
150 return 0;
151 }
152
153 /// Get the indent of \p Level from \p IndentForLevel.
154 ///
155 /// \p IndentForLevel must contain the indent for the level \c l
156 /// at \p IndentForLevel[l], or a value < 0 if the indent for
157 /// that level is unknown.
getIndent(unsigned Level) const158 unsigned getIndent(unsigned Level) const {
159 assert(Level < IndentForLevel.size());
160 if (IndentForLevel[Level] != -1)
161 return IndentForLevel[Level];
162 if (Level == 0)
163 return 0;
164 return getIndent(Level - 1) + Style.IndentWidth;
165 }
166
167 const FormatStyle &Style;
168 const AdditionalKeywords &Keywords;
169 const unsigned AdditionalIndent;
170
171 /// The indent in characters for each level. It remembers the indent of
172 /// previous lines (that are not PP directives) of equal or lower levels. This
173 /// is used to align formatted lines to the indent of previous non-formatted
174 /// lines. Think about the --lines parameter of clang-format.
175 SmallVector<int> IndentForLevel;
176
177 /// Offset of the current line relative to the indent level.
178 ///
179 /// For example, the 'public' keywords is often indented with a negative
180 /// offset.
181 int Offset = 0;
182
183 /// The current line's indent.
184 unsigned Indent = 0;
185 };
186
getMatchingNamespaceToken(const AnnotatedLine * Line,const SmallVectorImpl<AnnotatedLine * > & AnnotatedLines)187 const FormatToken *getMatchingNamespaceToken(
188 const AnnotatedLine *Line,
189 const SmallVectorImpl<AnnotatedLine *> &AnnotatedLines) {
190 if (!Line->startsWith(tok::r_brace))
191 return nullptr;
192 size_t StartLineIndex = Line->MatchingOpeningBlockLineIndex;
193 if (StartLineIndex == UnwrappedLine::kInvalidIndex)
194 return nullptr;
195 assert(StartLineIndex < AnnotatedLines.size());
196 return AnnotatedLines[StartLineIndex]->First->getNamespaceToken();
197 }
198
getNamespaceTokenText(const AnnotatedLine * Line)199 StringRef getNamespaceTokenText(const AnnotatedLine *Line) {
200 const FormatToken *NamespaceToken = Line->First->getNamespaceToken();
201 return NamespaceToken ? NamespaceToken->TokenText : StringRef();
202 }
203
getMatchingNamespaceTokenText(const AnnotatedLine * Line,const SmallVectorImpl<AnnotatedLine * > & AnnotatedLines)204 StringRef getMatchingNamespaceTokenText(
205 const AnnotatedLine *Line,
206 const SmallVectorImpl<AnnotatedLine *> &AnnotatedLines) {
207 const FormatToken *NamespaceToken =
208 getMatchingNamespaceToken(Line, AnnotatedLines);
209 return NamespaceToken ? NamespaceToken->TokenText : StringRef();
210 }
211
212 class LineJoiner {
213 public:
LineJoiner(const FormatStyle & Style,const AdditionalKeywords & Keywords,const SmallVectorImpl<AnnotatedLine * > & Lines)214 LineJoiner(const FormatStyle &Style, const AdditionalKeywords &Keywords,
215 const SmallVectorImpl<AnnotatedLine *> &Lines)
216 : Style(Style), Keywords(Keywords), End(Lines.end()), Next(Lines.begin()),
217 AnnotatedLines(Lines) {}
218
219 /// Returns the next line, merging multiple lines into one if possible.
getNextMergedLine(bool DryRun,LevelIndentTracker & IndentTracker)220 const AnnotatedLine *getNextMergedLine(bool DryRun,
221 LevelIndentTracker &IndentTracker) {
222 if (Next == End)
223 return nullptr;
224 const AnnotatedLine *Current = *Next;
225 IndentTracker.nextLine(*Current);
226 unsigned MergedLines = tryFitMultipleLinesInOne(IndentTracker, Next, End);
227 if (MergedLines > 0 && Style.ColumnLimit == 0) {
228 // Disallow line merging if there is a break at the start of one of the
229 // input lines.
230 for (unsigned i = 0; i < MergedLines; ++i)
231 if (Next[i + 1]->First->NewlinesBefore > 0)
232 MergedLines = 0;
233 }
234 if (!DryRun)
235 for (unsigned i = 0; i < MergedLines; ++i)
236 join(*Next[0], *Next[i + 1]);
237 Next = Next + MergedLines + 1;
238 return Current;
239 }
240
241 private:
242 /// Calculates how many lines can be merged into 1 starting at \p I.
243 unsigned
tryFitMultipleLinesInOne(LevelIndentTracker & IndentTracker,SmallVectorImpl<AnnotatedLine * >::const_iterator I,SmallVectorImpl<AnnotatedLine * >::const_iterator E)244 tryFitMultipleLinesInOne(LevelIndentTracker &IndentTracker,
245 SmallVectorImpl<AnnotatedLine *>::const_iterator I,
246 SmallVectorImpl<AnnotatedLine *>::const_iterator E) {
247 const unsigned Indent = IndentTracker.getIndent();
248
249 // Can't join the last line with anything.
250 if (I + 1 == E)
251 return 0;
252 // We can never merge stuff if there are trailing line comments.
253 const AnnotatedLine *TheLine = *I;
254 if (TheLine->Last->is(TT_LineComment))
255 return 0;
256 const auto &NextLine = *I[1];
257 if (NextLine.Type == LT_Invalid || NextLine.First->MustBreakBefore)
258 return 0;
259 if (TheLine->InPPDirective &&
260 (!NextLine.InPPDirective || NextLine.First->HasUnescapedNewline)) {
261 return 0;
262 }
263
264 if (Style.ColumnLimit > 0 && Indent > Style.ColumnLimit)
265 return 0;
266
267 unsigned Limit =
268 Style.ColumnLimit == 0 ? UINT_MAX : Style.ColumnLimit - Indent;
269 // If we already exceed the column limit, we set 'Limit' to 0. The different
270 // tryMerge..() functions can then decide whether to still do merging.
271 Limit = TheLine->Last->TotalLength > Limit
272 ? 0
273 : Limit - TheLine->Last->TotalLength;
274
275 if (TheLine->Last->is(TT_FunctionLBrace) &&
276 TheLine->First == TheLine->Last &&
277 !Style.BraceWrapping.SplitEmptyFunction &&
278 NextLine.First->is(tok::r_brace)) {
279 return tryMergeSimpleBlock(I, E, Limit);
280 }
281
282 const auto *PreviousLine = I != AnnotatedLines.begin() ? I[-1] : nullptr;
283 // Handle empty record blocks where the brace has already been wrapped.
284 if (PreviousLine && TheLine->Last->is(tok::l_brace) &&
285 TheLine->First == TheLine->Last) {
286 bool EmptyBlock = NextLine.First->is(tok::r_brace);
287
288 const FormatToken *Tok = PreviousLine->First;
289 if (Tok && Tok->is(tok::comment))
290 Tok = Tok->getNextNonComment();
291
292 if (Tok && Tok->getNamespaceToken()) {
293 return !Style.BraceWrapping.SplitEmptyNamespace && EmptyBlock
294 ? tryMergeSimpleBlock(I, E, Limit)
295 : 0;
296 }
297
298 if (Tok && Tok->is(tok::kw_typedef))
299 Tok = Tok->getNextNonComment();
300 if (Tok && Tok->isOneOf(tok::kw_class, tok::kw_struct, tok::kw_union,
301 tok::kw_extern, Keywords.kw_interface)) {
302 return !Style.BraceWrapping.SplitEmptyRecord && EmptyBlock
303 ? tryMergeSimpleBlock(I, E, Limit)
304 : 0;
305 }
306
307 if (Tok && Tok->is(tok::kw_template) &&
308 Style.BraceWrapping.SplitEmptyRecord && EmptyBlock) {
309 return 0;
310 }
311 }
312
313 auto ShouldMergeShortFunctions = [this, &I, &NextLine, PreviousLine,
314 TheLine]() {
315 if (Style.AllowShortFunctionsOnASingleLine == FormatStyle::SFS_All)
316 return true;
317 if (Style.AllowShortFunctionsOnASingleLine >= FormatStyle::SFS_Empty &&
318 NextLine.First->is(tok::r_brace)) {
319 return true;
320 }
321
322 if (Style.AllowShortFunctionsOnASingleLine &
323 FormatStyle::SFS_InlineOnly) {
324 // Just checking TheLine->Level != 0 is not enough, because it
325 // provokes treating functions inside indented namespaces as short.
326 if (Style.isJavaScript() && TheLine->Last->is(TT_FunctionLBrace))
327 return true;
328
329 if (TheLine->Level != 0) {
330 if (!PreviousLine)
331 return false;
332
333 // TODO: Use IndentTracker to avoid loop?
334 // Find the last line with lower level.
335 const AnnotatedLine *Line = nullptr;
336 for (auto J = I - 1; J >= AnnotatedLines.begin(); --J) {
337 assert(*J);
338 if (!(*J)->InPPDirective && !(*J)->isComment() &&
339 (*J)->Level < TheLine->Level) {
340 Line = *J;
341 break;
342 }
343 }
344
345 if (!Line)
346 return false;
347
348 // Check if the found line starts a record.
349 const auto *LastNonComment = Line->getLastNonComment();
350 // There must be another token (usually `{`), because we chose a
351 // non-PPDirective and non-comment line that has a smaller level.
352 assert(LastNonComment);
353 return isRecordLBrace(*LastNonComment);
354 }
355 }
356
357 return false;
358 };
359
360 bool MergeShortFunctions = ShouldMergeShortFunctions();
361
362 const auto *FirstNonComment = TheLine->getFirstNonComment();
363 if (!FirstNonComment)
364 return 0;
365 // FIXME: There are probably cases where we should use FirstNonComment
366 // instead of TheLine->First.
367
368 if (Style.CompactNamespaces) {
369 if (const auto *NSToken = TheLine->First->getNamespaceToken()) {
370 int J = 1;
371 assert(TheLine->MatchingClosingBlockLineIndex > 0);
372 for (auto ClosingLineIndex = TheLine->MatchingClosingBlockLineIndex - 1;
373 I + J != E && NSToken->TokenText == getNamespaceTokenText(I[J]) &&
374 ClosingLineIndex == I[J]->MatchingClosingBlockLineIndex &&
375 I[J]->Last->TotalLength < Limit;
376 ++J, --ClosingLineIndex) {
377 Limit -= I[J]->Last->TotalLength;
378
379 // Reduce indent level for bodies of namespaces which were compacted,
380 // but only if their content was indented in the first place.
381 auto *ClosingLine = AnnotatedLines.begin() + ClosingLineIndex + 1;
382 const int OutdentBy = I[J]->Level - TheLine->Level;
383 assert(OutdentBy >= 0);
384 for (auto *CompactedLine = I + J; CompactedLine <= ClosingLine;
385 ++CompactedLine) {
386 if (!(*CompactedLine)->InPPDirective) {
387 const int Level = (*CompactedLine)->Level;
388 (*CompactedLine)->Level = std::max(Level - OutdentBy, 0);
389 }
390 }
391 }
392 return J - 1;
393 }
394
395 if (auto nsToken = getMatchingNamespaceToken(TheLine, AnnotatedLines)) {
396 int i = 0;
397 unsigned openingLine = TheLine->MatchingOpeningBlockLineIndex - 1;
398 for (; I + 1 + i != E &&
399 nsToken->TokenText ==
400 getMatchingNamespaceTokenText(I[i + 1], AnnotatedLines) &&
401 openingLine == I[i + 1]->MatchingOpeningBlockLineIndex;
402 i++, --openingLine) {
403 // No space between consecutive braces.
404 I[i + 1]->First->SpacesRequiredBefore =
405 I[i]->Last->isNot(tok::r_brace);
406
407 // Indent like the outer-most namespace.
408 IndentTracker.nextLine(*I[i + 1]);
409 }
410 return i;
411 }
412 }
413
414 const auto *LastNonComment = TheLine->getLastNonComment();
415 assert(LastNonComment);
416 // FIXME: There are probably cases where we should use LastNonComment
417 // instead of TheLine->Last.
418
419 // Try to merge a function block with left brace unwrapped.
420 if (LastNonComment->is(TT_FunctionLBrace) &&
421 TheLine->First != LastNonComment) {
422 return MergeShortFunctions ? tryMergeSimpleBlock(I, E, Limit) : 0;
423 }
424 // Try to merge a control statement block with left brace unwrapped.
425 if (TheLine->Last->is(tok::l_brace) && FirstNonComment != TheLine->Last &&
426 FirstNonComment->isOneOf(tok::kw_if, tok::kw_while, tok::kw_for,
427 TT_ForEachMacro)) {
428 return Style.AllowShortBlocksOnASingleLine != FormatStyle::SBS_Never
429 ? tryMergeSimpleBlock(I, E, Limit)
430 : 0;
431 }
432 // Try to merge a control statement block with left brace wrapped.
433 if (NextLine.First->is(tok::l_brace)) {
434 if ((TheLine->First->isOneOf(tok::kw_if, tok::kw_else, tok::kw_while,
435 tok::kw_for, tok::kw_switch, tok::kw_try,
436 tok::kw_do, TT_ForEachMacro) ||
437 (TheLine->First->is(tok::r_brace) && TheLine->First->Next &&
438 TheLine->First->Next->isOneOf(tok::kw_else, tok::kw_catch))) &&
439 Style.BraceWrapping.AfterControlStatement ==
440 FormatStyle::BWACS_MultiLine) {
441 // If possible, merge the next line's wrapped left brace with the
442 // current line. Otherwise, leave it on the next line, as this is a
443 // multi-line control statement.
444 return (Style.ColumnLimit == 0 || TheLine->Level * Style.IndentWidth +
445 TheLine->Last->TotalLength <=
446 Style.ColumnLimit)
447 ? 1
448 : 0;
449 }
450 if (TheLine->First->isOneOf(tok::kw_if, tok::kw_else, tok::kw_while,
451 tok::kw_for, TT_ForEachMacro)) {
452 return (Style.BraceWrapping.AfterControlStatement ==
453 FormatStyle::BWACS_Always)
454 ? tryMergeSimpleBlock(I, E, Limit)
455 : 0;
456 }
457 if (TheLine->First->isOneOf(tok::kw_else, tok::kw_catch) &&
458 Style.BraceWrapping.AfterControlStatement ==
459 FormatStyle::BWACS_MultiLine) {
460 // This case if different from the upper BWACS_MultiLine processing
461 // in that a preceding r_brace is not on the same line as else/catch
462 // most likely because of BeforeElse/BeforeCatch set to true.
463 // If the line length doesn't fit ColumnLimit, leave l_brace on the
464 // next line to respect the BWACS_MultiLine.
465 return (Style.ColumnLimit == 0 ||
466 TheLine->Last->TotalLength <= Style.ColumnLimit)
467 ? 1
468 : 0;
469 }
470 }
471 if (PreviousLine && TheLine->First->is(tok::l_brace)) {
472 switch (PreviousLine->First->Tok.getKind()) {
473 case tok::at:
474 // Don't merge block with left brace wrapped after ObjC special blocks.
475 if (PreviousLine->First->Next) {
476 tok::ObjCKeywordKind kwId =
477 PreviousLine->First->Next->Tok.getObjCKeywordID();
478 if (kwId == tok::objc_autoreleasepool ||
479 kwId == tok::objc_synchronized) {
480 return 0;
481 }
482 }
483 break;
484
485 case tok::kw_case:
486 case tok::kw_default:
487 // Don't merge block with left brace wrapped after case labels.
488 return 0;
489
490 default:
491 break;
492 }
493 }
494
495 // Don't merge an empty template class or struct if SplitEmptyRecords
496 // is defined.
497 if (PreviousLine && Style.BraceWrapping.SplitEmptyRecord &&
498 TheLine->Last->is(tok::l_brace) && PreviousLine->Last) {
499 const FormatToken *Previous = PreviousLine->Last;
500 if (Previous) {
501 if (Previous->is(tok::comment))
502 Previous = Previous->getPreviousNonComment();
503 if (Previous) {
504 if (Previous->is(tok::greater) && !PreviousLine->InPPDirective)
505 return 0;
506 if (Previous->is(tok::identifier)) {
507 const FormatToken *PreviousPrevious =
508 Previous->getPreviousNonComment();
509 if (PreviousPrevious &&
510 PreviousPrevious->isOneOf(tok::kw_class, tok::kw_struct)) {
511 return 0;
512 }
513 }
514 }
515 }
516 }
517
518 if (TheLine->Last->is(tok::l_brace)) {
519 bool ShouldMerge = false;
520 // Try to merge records.
521 if (TheLine->Last->is(TT_EnumLBrace)) {
522 ShouldMerge = Style.AllowShortEnumsOnASingleLine;
523 } else if (TheLine->Last->is(TT_RequiresExpressionLBrace)) {
524 ShouldMerge = Style.AllowShortCompoundRequirementOnASingleLine;
525 } else if (TheLine->Last->isOneOf(TT_ClassLBrace, TT_StructLBrace)) {
526 // NOTE: We use AfterClass (whereas AfterStruct exists) for both classes
527 // and structs, but it seems that wrapping is still handled correctly
528 // elsewhere.
529 ShouldMerge = !Style.BraceWrapping.AfterClass ||
530 (NextLine.First->is(tok::r_brace) &&
531 !Style.BraceWrapping.SplitEmptyRecord);
532 } else if (TheLine->InPPDirective ||
533 !TheLine->First->isOneOf(tok::kw_class, tok::kw_enum,
534 tok::kw_struct)) {
535 // Try to merge a block with left brace unwrapped that wasn't yet
536 // covered.
537 ShouldMerge = !Style.BraceWrapping.AfterFunction ||
538 (NextLine.First->is(tok::r_brace) &&
539 !Style.BraceWrapping.SplitEmptyFunction);
540 }
541 return ShouldMerge ? tryMergeSimpleBlock(I, E, Limit) : 0;
542 }
543
544 // Try to merge a function block with left brace wrapped.
545 if (NextLine.First->is(TT_FunctionLBrace) &&
546 Style.BraceWrapping.AfterFunction) {
547 if (NextLine.Last->is(TT_LineComment))
548 return 0;
549
550 // Check for Limit <= 2 to account for the " {".
551 if (Limit <= 2 || (Style.ColumnLimit == 0 && containsMustBreak(TheLine)))
552 return 0;
553 Limit -= 2;
554
555 unsigned MergedLines = 0;
556 if (MergeShortFunctions ||
557 (Style.AllowShortFunctionsOnASingleLine >= FormatStyle::SFS_Empty &&
558 NextLine.First == NextLine.Last && I + 2 != E &&
559 I[2]->First->is(tok::r_brace))) {
560 MergedLines = tryMergeSimpleBlock(I + 1, E, Limit);
561 // If we managed to merge the block, count the function header, which is
562 // on a separate line.
563 if (MergedLines > 0)
564 ++MergedLines;
565 }
566 return MergedLines;
567 }
568 auto IsElseLine = [&TheLine]() -> bool {
569 const FormatToken *First = TheLine->First;
570 if (First->is(tok::kw_else))
571 return true;
572
573 return First->is(tok::r_brace) && First->Next &&
574 First->Next->is(tok::kw_else);
575 };
576 if (TheLine->First->is(tok::kw_if) ||
577 (IsElseLine() && (Style.AllowShortIfStatementsOnASingleLine ==
578 FormatStyle::SIS_AllIfsAndElse))) {
579 return Style.AllowShortIfStatementsOnASingleLine
580 ? tryMergeSimpleControlStatement(I, E, Limit)
581 : 0;
582 }
583 if (TheLine->First->isOneOf(tok::kw_for, tok::kw_while, tok::kw_do,
584 TT_ForEachMacro)) {
585 return Style.AllowShortLoopsOnASingleLine
586 ? tryMergeSimpleControlStatement(I, E, Limit)
587 : 0;
588 }
589 if (TheLine->First->isOneOf(tok::kw_case, tok::kw_default)) {
590 return Style.AllowShortCaseLabelsOnASingleLine
591 ? tryMergeShortCaseLabels(I, E, Limit)
592 : 0;
593 }
594 if (TheLine->InPPDirective &&
595 (TheLine->First->HasUnescapedNewline || TheLine->First->IsFirst)) {
596 return tryMergeSimplePPDirective(I, E, Limit);
597 }
598 return 0;
599 }
600
601 unsigned
tryMergeSimplePPDirective(SmallVectorImpl<AnnotatedLine * >::const_iterator I,SmallVectorImpl<AnnotatedLine * >::const_iterator E,unsigned Limit)602 tryMergeSimplePPDirective(SmallVectorImpl<AnnotatedLine *>::const_iterator I,
603 SmallVectorImpl<AnnotatedLine *>::const_iterator E,
604 unsigned Limit) {
605 if (Limit == 0)
606 return 0;
607 if (I + 2 != E && I[2]->InPPDirective && !I[2]->First->HasUnescapedNewline)
608 return 0;
609 if (1 + I[1]->Last->TotalLength > Limit)
610 return 0;
611 return 1;
612 }
613
tryMergeSimpleControlStatement(SmallVectorImpl<AnnotatedLine * >::const_iterator I,SmallVectorImpl<AnnotatedLine * >::const_iterator E,unsigned Limit)614 unsigned tryMergeSimpleControlStatement(
615 SmallVectorImpl<AnnotatedLine *>::const_iterator I,
616 SmallVectorImpl<AnnotatedLine *>::const_iterator E, unsigned Limit) {
617 if (Limit == 0)
618 return 0;
619 if (Style.BraceWrapping.AfterControlStatement ==
620 FormatStyle::BWACS_Always &&
621 I[1]->First->is(tok::l_brace) &&
622 Style.AllowShortBlocksOnASingleLine == FormatStyle::SBS_Never) {
623 return 0;
624 }
625 if (I[1]->InPPDirective != (*I)->InPPDirective ||
626 (I[1]->InPPDirective && I[1]->First->HasUnescapedNewline)) {
627 return 0;
628 }
629 Limit = limitConsideringMacros(I + 1, E, Limit);
630 AnnotatedLine &Line = **I;
631 if (Line.First->isNot(tok::kw_do) && Line.First->isNot(tok::kw_else) &&
632 Line.Last->isNot(tok::kw_else) && Line.Last->isNot(tok::r_paren)) {
633 return 0;
634 }
635 // Only merge `do while` if `do` is the only statement on the line.
636 if (Line.First->is(tok::kw_do) && Line.Last->isNot(tok::kw_do))
637 return 0;
638 if (1 + I[1]->Last->TotalLength > Limit)
639 return 0;
640 // Don't merge with loops, ifs, a single semicolon or a line comment.
641 if (I[1]->First->isOneOf(tok::semi, tok::kw_if, tok::kw_for, tok::kw_while,
642 TT_ForEachMacro, TT_LineComment)) {
643 return 0;
644 }
645 // Only inline simple if's (no nested if or else), unless specified
646 if (Style.AllowShortIfStatementsOnASingleLine ==
647 FormatStyle::SIS_WithoutElse) {
648 if (I + 2 != E && Line.startsWith(tok::kw_if) &&
649 I[2]->First->is(tok::kw_else)) {
650 return 0;
651 }
652 }
653 return 1;
654 }
655
656 unsigned
tryMergeShortCaseLabels(SmallVectorImpl<AnnotatedLine * >::const_iterator I,SmallVectorImpl<AnnotatedLine * >::const_iterator E,unsigned Limit)657 tryMergeShortCaseLabels(SmallVectorImpl<AnnotatedLine *>::const_iterator I,
658 SmallVectorImpl<AnnotatedLine *>::const_iterator E,
659 unsigned Limit) {
660 if (Limit == 0 || I + 1 == E ||
661 I[1]->First->isOneOf(tok::kw_case, tok::kw_default)) {
662 return 0;
663 }
664 if (I[0]->Last->is(tok::l_brace) || I[1]->First->is(tok::l_brace))
665 return 0;
666 unsigned NumStmts = 0;
667 unsigned Length = 0;
668 bool EndsWithComment = false;
669 bool InPPDirective = I[0]->InPPDirective;
670 bool InMacroBody = I[0]->InMacroBody;
671 const unsigned Level = I[0]->Level;
672 for (; NumStmts < 3; ++NumStmts) {
673 if (I + 1 + NumStmts == E)
674 break;
675 const AnnotatedLine *Line = I[1 + NumStmts];
676 if (Line->InPPDirective != InPPDirective)
677 break;
678 if (Line->InMacroBody != InMacroBody)
679 break;
680 if (Line->First->isOneOf(tok::kw_case, tok::kw_default, tok::r_brace))
681 break;
682 if (Line->First->isOneOf(tok::kw_if, tok::kw_for, tok::kw_switch,
683 tok::kw_while) ||
684 EndsWithComment) {
685 return 0;
686 }
687 if (Line->First->is(tok::comment)) {
688 if (Level != Line->Level)
689 return 0;
690 SmallVectorImpl<AnnotatedLine *>::const_iterator J = I + 2 + NumStmts;
691 for (; J != E; ++J) {
692 Line = *J;
693 if (Line->InPPDirective != InPPDirective)
694 break;
695 if (Line->First->isOneOf(tok::kw_case, tok::kw_default, tok::r_brace))
696 break;
697 if (Line->First->isNot(tok::comment) || Level != Line->Level)
698 return 0;
699 }
700 break;
701 }
702 if (Line->Last->is(tok::comment))
703 EndsWithComment = true;
704 Length += I[1 + NumStmts]->Last->TotalLength + 1; // 1 for the space.
705 }
706 if (NumStmts == 0 || NumStmts == 3 || Length > Limit)
707 return 0;
708 return NumStmts;
709 }
710
711 unsigned
tryMergeSimpleBlock(SmallVectorImpl<AnnotatedLine * >::const_iterator I,SmallVectorImpl<AnnotatedLine * >::const_iterator E,unsigned Limit)712 tryMergeSimpleBlock(SmallVectorImpl<AnnotatedLine *>::const_iterator I,
713 SmallVectorImpl<AnnotatedLine *>::const_iterator E,
714 unsigned Limit) {
715 // Don't merge with a preprocessor directive.
716 if (I[1]->Type == LT_PreprocessorDirective)
717 return 0;
718
719 AnnotatedLine &Line = **I;
720
721 // Don't merge ObjC @ keywords and methods.
722 // FIXME: If an option to allow short exception handling clauses on a single
723 // line is added, change this to not return for @try and friends.
724 if (Style.Language != FormatStyle::LK_Java &&
725 Line.First->isOneOf(tok::at, tok::minus, tok::plus)) {
726 return 0;
727 }
728
729 // Check that the current line allows merging. This depends on whether we
730 // are in a control flow statements as well as several style flags.
731 if (Line.First->is(tok::kw_case) ||
732 (Line.First->Next && Line.First->Next->is(tok::kw_else))) {
733 return 0;
734 }
735 // default: in switch statement
736 if (Line.First->is(tok::kw_default)) {
737 const FormatToken *Tok = Line.First->getNextNonComment();
738 if (Tok && Tok->is(tok::colon))
739 return 0;
740 }
741
742 auto IsCtrlStmt = [](const auto &Line) {
743 return Line.First->isOneOf(tok::kw_if, tok::kw_else, tok::kw_while,
744 tok::kw_do, tok::kw_for, TT_ForEachMacro);
745 };
746
747 const bool IsSplitBlock =
748 Style.AllowShortBlocksOnASingleLine == FormatStyle::SBS_Never ||
749 (Style.AllowShortBlocksOnASingleLine == FormatStyle::SBS_Empty &&
750 I[1]->First->isNot(tok::r_brace));
751
752 if (IsCtrlStmt(Line) ||
753 Line.First->isOneOf(tok::kw_try, tok::kw___try, tok::kw_catch,
754 tok::kw___finally, tok::r_brace,
755 Keywords.kw___except)) {
756 if (IsSplitBlock)
757 return 0;
758 // Don't merge when we can't except the case when
759 // the control statement block is empty
760 if (!Style.AllowShortIfStatementsOnASingleLine &&
761 Line.First->isOneOf(tok::kw_if, tok::kw_else) &&
762 !Style.BraceWrapping.AfterControlStatement &&
763 I[1]->First->isNot(tok::r_brace)) {
764 return 0;
765 }
766 if (!Style.AllowShortIfStatementsOnASingleLine &&
767 Line.First->isOneOf(tok::kw_if, tok::kw_else) &&
768 Style.BraceWrapping.AfterControlStatement ==
769 FormatStyle::BWACS_Always &&
770 I + 2 != E && I[2]->First->isNot(tok::r_brace)) {
771 return 0;
772 }
773 if (!Style.AllowShortLoopsOnASingleLine &&
774 Line.First->isOneOf(tok::kw_while, tok::kw_do, tok::kw_for,
775 TT_ForEachMacro) &&
776 !Style.BraceWrapping.AfterControlStatement &&
777 I[1]->First->isNot(tok::r_brace)) {
778 return 0;
779 }
780 if (!Style.AllowShortLoopsOnASingleLine &&
781 Line.First->isOneOf(tok::kw_while, tok::kw_do, tok::kw_for,
782 TT_ForEachMacro) &&
783 Style.BraceWrapping.AfterControlStatement ==
784 FormatStyle::BWACS_Always &&
785 I + 2 != E && I[2]->First->isNot(tok::r_brace)) {
786 return 0;
787 }
788 // FIXME: Consider an option to allow short exception handling clauses on
789 // a single line.
790 // FIXME: This isn't covered by tests.
791 // FIXME: For catch, __except, __finally the first token on the line
792 // is '}', so this isn't correct here.
793 if (Line.First->isOneOf(tok::kw_try, tok::kw___try, tok::kw_catch,
794 Keywords.kw___except, tok::kw___finally)) {
795 return 0;
796 }
797 }
798
799 if (const auto *LastNonComment = Line.getLastNonComment();
800 LastNonComment && LastNonComment->is(tok::l_brace)) {
801 if (IsSplitBlock && Line.First == Line.Last &&
802 I > AnnotatedLines.begin() &&
803 (I[-1]->endsWith(tok::kw_else) || IsCtrlStmt(*I[-1]))) {
804 return 0;
805 }
806 FormatToken *Tok = I[1]->First;
807 auto ShouldMerge = [Tok]() {
808 if (Tok->isNot(tok::r_brace) || Tok->MustBreakBefore)
809 return false;
810 const FormatToken *Next = Tok->getNextNonComment();
811 return !Next || Next->is(tok::semi);
812 };
813
814 if (ShouldMerge()) {
815 // We merge empty blocks even if the line exceeds the column limit.
816 Tok->SpacesRequiredBefore =
817 (Style.SpaceInEmptyBlock || Line.Last->is(tok::comment)) ? 1 : 0;
818 Tok->CanBreakBefore = true;
819 return 1;
820 } else if (Limit != 0 && !Line.startsWithNamespace() &&
821 !startsExternCBlock(Line)) {
822 // We don't merge short records.
823 if (isRecordLBrace(*Line.Last))
824 return 0;
825
826 // Check that we still have three lines and they fit into the limit.
827 if (I + 2 == E || I[2]->Type == LT_Invalid)
828 return 0;
829 Limit = limitConsideringMacros(I + 2, E, Limit);
830
831 if (!nextTwoLinesFitInto(I, Limit))
832 return 0;
833
834 // Second, check that the next line does not contain any braces - if it
835 // does, readability declines when putting it into a single line.
836 if (I[1]->Last->is(TT_LineComment))
837 return 0;
838 do {
839 if (Tok->is(tok::l_brace) && Tok->isNot(BK_BracedInit))
840 return 0;
841 Tok = Tok->Next;
842 } while (Tok);
843
844 // Last, check that the third line starts with a closing brace.
845 Tok = I[2]->First;
846 if (Tok->isNot(tok::r_brace))
847 return 0;
848
849 // Don't merge "if (a) { .. } else {".
850 if (Tok->Next && Tok->Next->is(tok::kw_else))
851 return 0;
852
853 // Don't merge a trailing multi-line control statement block like:
854 // } else if (foo &&
855 // bar)
856 // { <-- current Line
857 // baz();
858 // }
859 if (Line.First == Line.Last && Line.First->isNot(TT_FunctionLBrace) &&
860 Style.BraceWrapping.AfterControlStatement ==
861 FormatStyle::BWACS_MultiLine) {
862 return 0;
863 }
864
865 return 2;
866 }
867 } else if (I[1]->First->is(tok::l_brace)) {
868 if (I[1]->Last->is(TT_LineComment))
869 return 0;
870
871 // Check for Limit <= 2 to account for the " {".
872 if (Limit <= 2 || (Style.ColumnLimit == 0 && containsMustBreak(*I)))
873 return 0;
874 Limit -= 2;
875 unsigned MergedLines = 0;
876 if (Style.AllowShortBlocksOnASingleLine != FormatStyle::SBS_Never ||
877 (I[1]->First == I[1]->Last && I + 2 != E &&
878 I[2]->First->is(tok::r_brace))) {
879 MergedLines = tryMergeSimpleBlock(I + 1, E, Limit);
880 // If we managed to merge the block, count the statement header, which
881 // is on a separate line.
882 if (MergedLines > 0)
883 ++MergedLines;
884 }
885 return MergedLines;
886 }
887 return 0;
888 }
889
890 /// Returns the modified column limit for \p I if it is inside a macro and
891 /// needs a trailing '\'.
892 unsigned
limitConsideringMacros(SmallVectorImpl<AnnotatedLine * >::const_iterator I,SmallVectorImpl<AnnotatedLine * >::const_iterator E,unsigned Limit)893 limitConsideringMacros(SmallVectorImpl<AnnotatedLine *>::const_iterator I,
894 SmallVectorImpl<AnnotatedLine *>::const_iterator E,
895 unsigned Limit) {
896 if (I[0]->InPPDirective && I + 1 != E &&
897 !I[1]->First->HasUnescapedNewline && I[1]->First->isNot(tok::eof)) {
898 return Limit < 2 ? 0 : Limit - 2;
899 }
900 return Limit;
901 }
902
nextTwoLinesFitInto(SmallVectorImpl<AnnotatedLine * >::const_iterator I,unsigned Limit)903 bool nextTwoLinesFitInto(SmallVectorImpl<AnnotatedLine *>::const_iterator I,
904 unsigned Limit) {
905 if (I[1]->First->MustBreakBefore || I[2]->First->MustBreakBefore)
906 return false;
907 return 1 + I[1]->Last->TotalLength + 1 + I[2]->Last->TotalLength <= Limit;
908 }
909
containsMustBreak(const AnnotatedLine * Line)910 bool containsMustBreak(const AnnotatedLine *Line) {
911 assert(Line->First);
912 // Ignore the first token, because in this situation, it applies more to the
913 // last token of the previous line.
914 for (const FormatToken *Tok = Line->First->Next; Tok; Tok = Tok->Next)
915 if (Tok->MustBreakBefore)
916 return true;
917 return false;
918 }
919
join(AnnotatedLine & A,const AnnotatedLine & B)920 void join(AnnotatedLine &A, const AnnotatedLine &B) {
921 assert(!A.Last->Next);
922 assert(!B.First->Previous);
923 if (B.Affected)
924 A.Affected = true;
925 A.Last->Next = B.First;
926 B.First->Previous = A.Last;
927 B.First->CanBreakBefore = true;
928 unsigned LengthA = A.Last->TotalLength + B.First->SpacesRequiredBefore;
929 for (FormatToken *Tok = B.First; Tok; Tok = Tok->Next) {
930 Tok->TotalLength += LengthA;
931 A.Last = Tok;
932 }
933 }
934
935 const FormatStyle &Style;
936 const AdditionalKeywords &Keywords;
937 const SmallVectorImpl<AnnotatedLine *>::const_iterator End;
938
939 SmallVectorImpl<AnnotatedLine *>::const_iterator Next;
940 const SmallVectorImpl<AnnotatedLine *> &AnnotatedLines;
941 };
942
markFinalized(FormatToken * Tok)943 static void markFinalized(FormatToken *Tok) {
944 if (Tok->is(tok::hash) && !Tok->Previous && Tok->Next &&
945 Tok->Next->isOneOf(tok::pp_if, tok::pp_ifdef, tok::pp_ifndef,
946 tok::pp_elif, tok::pp_elifdef, tok::pp_elifndef,
947 tok::pp_else, tok::pp_endif)) {
948 Tok = Tok->Next;
949 }
950 for (; Tok; Tok = Tok->Next) {
951 if (Tok->MacroCtx && Tok->MacroCtx->Role == MR_ExpandedArg) {
952 // In the first pass we format all macro arguments in the expanded token
953 // stream. Instead of finalizing the macro arguments, we mark that they
954 // will be modified as unexpanded arguments (as part of the macro call
955 // formatting) in the next pass.
956 Tok->MacroCtx->Role = MR_UnexpandedArg;
957 // Reset whether spaces or a line break are required before this token, as
958 // that is context dependent, and that context may change when formatting
959 // the macro call. For example, given M(x) -> 2 * x, and the macro call
960 // M(var), the token 'var' will have SpacesRequiredBefore = 1 after being
961 // formatted as part of the expanded macro, but SpacesRequiredBefore = 0
962 // for its position within the macro call.
963 Tok->SpacesRequiredBefore = 0;
964 if (!Tok->MustBreakBeforeFinalized)
965 Tok->MustBreakBefore = 0;
966 } else {
967 Tok->Finalized = true;
968 }
969 }
970 }
971
972 #ifndef NDEBUG
printLineState(const LineState & State)973 static void printLineState(const LineState &State) {
974 llvm::dbgs() << "State: ";
975 for (const ParenState &P : State.Stack) {
976 llvm::dbgs() << (P.Tok ? P.Tok->TokenText : "F") << "|" << P.Indent << "|"
977 << P.LastSpace << "|" << P.NestedBlockIndent << " ";
978 }
979 llvm::dbgs() << State.NextToken->TokenText << "\n";
980 }
981 #endif
982
983 /// Base class for classes that format one \c AnnotatedLine.
984 class LineFormatter {
985 public:
LineFormatter(ContinuationIndenter * Indenter,WhitespaceManager * Whitespaces,const FormatStyle & Style,UnwrappedLineFormatter * BlockFormatter)986 LineFormatter(ContinuationIndenter *Indenter, WhitespaceManager *Whitespaces,
987 const FormatStyle &Style,
988 UnwrappedLineFormatter *BlockFormatter)
989 : Indenter(Indenter), Whitespaces(Whitespaces), Style(Style),
990 BlockFormatter(BlockFormatter) {}
~LineFormatter()991 virtual ~LineFormatter() {}
992
993 /// Formats an \c AnnotatedLine and returns the penalty.
994 ///
995 /// If \p DryRun is \c false, directly applies the changes.
996 virtual unsigned formatLine(const AnnotatedLine &Line, unsigned FirstIndent,
997 unsigned FirstStartColumn, bool DryRun) = 0;
998
999 protected:
1000 /// If the \p State's next token is an r_brace closing a nested block,
1001 /// format the nested block before it.
1002 ///
1003 /// Returns \c true if all children could be placed successfully and adapts
1004 /// \p Penalty as well as \p State. If \p DryRun is false, also directly
1005 /// creates changes using \c Whitespaces.
1006 ///
1007 /// The crucial idea here is that children always get formatted upon
1008 /// encountering the closing brace right after the nested block. Now, if we
1009 /// are currently trying to keep the "}" on the same line (i.e. \p NewLine is
1010 /// \c false), the entire block has to be kept on the same line (which is only
1011 /// possible if it fits on the line, only contains a single statement, etc.
1012 ///
1013 /// If \p NewLine is true, we format the nested block on separate lines, i.e.
1014 /// break after the "{", format all lines with correct indentation and the put
1015 /// the closing "}" on yet another new line.
1016 ///
1017 /// This enables us to keep the simple structure of the
1018 /// \c UnwrappedLineFormatter, where we only have two options for each token:
1019 /// break or don't break.
formatChildren(LineState & State,bool NewLine,bool DryRun,unsigned & Penalty)1020 bool formatChildren(LineState &State, bool NewLine, bool DryRun,
1021 unsigned &Penalty) {
1022 const FormatToken *LBrace = State.NextToken->getPreviousNonComment();
1023 bool HasLBrace = LBrace && LBrace->is(tok::l_brace) && LBrace->is(BK_Block);
1024 FormatToken &Previous = *State.NextToken->Previous;
1025 if (Previous.Children.size() == 0 || (!HasLBrace && !LBrace->MacroParent)) {
1026 // The previous token does not open a block. Nothing to do. We don't
1027 // assert so that we can simply call this function for all tokens.
1028 return true;
1029 }
1030
1031 if (NewLine || Previous.MacroParent) {
1032 const ParenState &P = State.Stack.back();
1033
1034 int AdditionalIndent =
1035 P.Indent - Previous.Children[0]->Level * Style.IndentWidth;
1036 Penalty +=
1037 BlockFormatter->format(Previous.Children, DryRun, AdditionalIndent,
1038 /*FixBadIndentation=*/true);
1039 return true;
1040 }
1041
1042 if (Previous.Children[0]->First->MustBreakBefore)
1043 return false;
1044
1045 // Cannot merge into one line if this line ends on a comment.
1046 if (Previous.is(tok::comment))
1047 return false;
1048
1049 // Cannot merge multiple statements into a single line.
1050 if (Previous.Children.size() > 1)
1051 return false;
1052
1053 const AnnotatedLine *Child = Previous.Children[0];
1054 // We can't put the closing "}" on a line with a trailing comment.
1055 if (Child->Last->isTrailingComment())
1056 return false;
1057
1058 // If the child line exceeds the column limit, we wouldn't want to merge it.
1059 // We add +2 for the trailing " }".
1060 if (Style.ColumnLimit > 0 &&
1061 Child->Last->TotalLength + State.Column + 2 > Style.ColumnLimit) {
1062 return false;
1063 }
1064
1065 if (!DryRun) {
1066 Whitespaces->replaceWhitespace(
1067 *Child->First, /*Newlines=*/0, /*Spaces=*/1,
1068 /*StartOfTokenColumn=*/State.Column, /*IsAligned=*/false,
1069 State.Line->InPPDirective);
1070 }
1071 Penalty +=
1072 formatLine(*Child, State.Column + 1, /*FirstStartColumn=*/0, DryRun);
1073 if (!DryRun)
1074 markFinalized(Child->First);
1075
1076 State.Column += 1 + Child->Last->TotalLength;
1077 return true;
1078 }
1079
1080 ContinuationIndenter *Indenter;
1081
1082 private:
1083 WhitespaceManager *Whitespaces;
1084 const FormatStyle &Style;
1085 UnwrappedLineFormatter *BlockFormatter;
1086 };
1087
1088 /// Formatter that keeps the existing line breaks.
1089 class NoColumnLimitLineFormatter : public LineFormatter {
1090 public:
NoColumnLimitLineFormatter(ContinuationIndenter * Indenter,WhitespaceManager * Whitespaces,const FormatStyle & Style,UnwrappedLineFormatter * BlockFormatter)1091 NoColumnLimitLineFormatter(ContinuationIndenter *Indenter,
1092 WhitespaceManager *Whitespaces,
1093 const FormatStyle &Style,
1094 UnwrappedLineFormatter *BlockFormatter)
1095 : LineFormatter(Indenter, Whitespaces, Style, BlockFormatter) {}
1096
1097 /// Formats the line, simply keeping all of the input's line breaking
1098 /// decisions.
formatLine(const AnnotatedLine & Line,unsigned FirstIndent,unsigned FirstStartColumn,bool DryRun)1099 unsigned formatLine(const AnnotatedLine &Line, unsigned FirstIndent,
1100 unsigned FirstStartColumn, bool DryRun) override {
1101 assert(!DryRun);
1102 LineState State = Indenter->getInitialState(FirstIndent, FirstStartColumn,
1103 &Line, /*DryRun=*/false);
1104 while (State.NextToken) {
1105 bool Newline =
1106 Indenter->mustBreak(State) ||
1107 (Indenter->canBreak(State) && State.NextToken->NewlinesBefore > 0);
1108 unsigned Penalty = 0;
1109 formatChildren(State, Newline, /*DryRun=*/false, Penalty);
1110 Indenter->addTokenToState(State, Newline, /*DryRun=*/false);
1111 }
1112 return 0;
1113 }
1114 };
1115
1116 /// Formatter that puts all tokens into a single line without breaks.
1117 class NoLineBreakFormatter : public LineFormatter {
1118 public:
NoLineBreakFormatter(ContinuationIndenter * Indenter,WhitespaceManager * Whitespaces,const FormatStyle & Style,UnwrappedLineFormatter * BlockFormatter)1119 NoLineBreakFormatter(ContinuationIndenter *Indenter,
1120 WhitespaceManager *Whitespaces, const FormatStyle &Style,
1121 UnwrappedLineFormatter *BlockFormatter)
1122 : LineFormatter(Indenter, Whitespaces, Style, BlockFormatter) {}
1123
1124 /// Puts all tokens into a single line.
formatLine(const AnnotatedLine & Line,unsigned FirstIndent,unsigned FirstStartColumn,bool DryRun)1125 unsigned formatLine(const AnnotatedLine &Line, unsigned FirstIndent,
1126 unsigned FirstStartColumn, bool DryRun) override {
1127 unsigned Penalty = 0;
1128 LineState State =
1129 Indenter->getInitialState(FirstIndent, FirstStartColumn, &Line, DryRun);
1130 while (State.NextToken) {
1131 formatChildren(State, /*NewLine=*/false, DryRun, Penalty);
1132 Indenter->addTokenToState(
1133 State, /*Newline=*/State.NextToken->MustBreakBefore, DryRun);
1134 }
1135 return Penalty;
1136 }
1137 };
1138
1139 /// Finds the best way to break lines.
1140 class OptimizingLineFormatter : public LineFormatter {
1141 public:
OptimizingLineFormatter(ContinuationIndenter * Indenter,WhitespaceManager * Whitespaces,const FormatStyle & Style,UnwrappedLineFormatter * BlockFormatter)1142 OptimizingLineFormatter(ContinuationIndenter *Indenter,
1143 WhitespaceManager *Whitespaces,
1144 const FormatStyle &Style,
1145 UnwrappedLineFormatter *BlockFormatter)
1146 : LineFormatter(Indenter, Whitespaces, Style, BlockFormatter) {}
1147
1148 /// Formats the line by finding the best line breaks with line lengths
1149 /// below the column limit.
formatLine(const AnnotatedLine & Line,unsigned FirstIndent,unsigned FirstStartColumn,bool DryRun)1150 unsigned formatLine(const AnnotatedLine &Line, unsigned FirstIndent,
1151 unsigned FirstStartColumn, bool DryRun) override {
1152 LineState State =
1153 Indenter->getInitialState(FirstIndent, FirstStartColumn, &Line, DryRun);
1154
1155 // If the ObjC method declaration does not fit on a line, we should format
1156 // it with one arg per line.
1157 if (State.Line->Type == LT_ObjCMethodDecl)
1158 State.Stack.back().BreakBeforeParameter = true;
1159
1160 // Find best solution in solution space.
1161 return analyzeSolutionSpace(State, DryRun);
1162 }
1163
1164 private:
1165 struct CompareLineStatePointers {
operator ()clang::format::__anon1029540c0111::OptimizingLineFormatter::CompareLineStatePointers1166 bool operator()(LineState *obj1, LineState *obj2) const {
1167 return *obj1 < *obj2;
1168 }
1169 };
1170
1171 /// A pair of <penalty, count> that is used to prioritize the BFS on.
1172 ///
1173 /// In case of equal penalties, we want to prefer states that were inserted
1174 /// first. During state generation we make sure that we insert states first
1175 /// that break the line as late as possible.
1176 typedef std::pair<unsigned, unsigned> OrderedPenalty;
1177
1178 /// An edge in the solution space from \c Previous->State to \c State,
1179 /// inserting a newline dependent on the \c NewLine.
1180 struct StateNode {
StateNodeclang::format::__anon1029540c0111::OptimizingLineFormatter::StateNode1181 StateNode(const LineState &State, bool NewLine, StateNode *Previous)
1182 : State(State), NewLine(NewLine), Previous(Previous) {}
1183 LineState State;
1184 bool NewLine;
1185 StateNode *Previous;
1186 };
1187
1188 /// An item in the prioritized BFS search queue. The \c StateNode's
1189 /// \c State has the given \c OrderedPenalty.
1190 typedef std::pair<OrderedPenalty, StateNode *> QueueItem;
1191
1192 /// The BFS queue type.
1193 typedef std::priority_queue<QueueItem, SmallVector<QueueItem>,
1194 std::greater<QueueItem>>
1195 QueueType;
1196
1197 /// Analyze the entire solution space starting from \p InitialState.
1198 ///
1199 /// This implements a variant of Dijkstra's algorithm on the graph that spans
1200 /// the solution space (\c LineStates are the nodes). The algorithm tries to
1201 /// find the shortest path (the one with lowest penalty) from \p InitialState
1202 /// to a state where all tokens are placed. Returns the penalty.
1203 ///
1204 /// If \p DryRun is \c false, directly applies the changes.
analyzeSolutionSpace(LineState & InitialState,bool DryRun)1205 unsigned analyzeSolutionSpace(LineState &InitialState, bool DryRun) {
1206 std::set<LineState *, CompareLineStatePointers> Seen;
1207
1208 // Increasing count of \c StateNode items we have created. This is used to
1209 // create a deterministic order independent of the container.
1210 unsigned Count = 0;
1211 QueueType Queue;
1212
1213 // Insert start element into queue.
1214 StateNode *RootNode =
1215 new (Allocator.Allocate()) StateNode(InitialState, false, nullptr);
1216 Queue.push(QueueItem(OrderedPenalty(0, Count), RootNode));
1217 ++Count;
1218
1219 unsigned Penalty = 0;
1220
1221 // While not empty, take first element and follow edges.
1222 while (!Queue.empty()) {
1223 // Quit if we still haven't found a solution by now.
1224 if (Count > 25000000)
1225 return 0;
1226
1227 Penalty = Queue.top().first.first;
1228 StateNode *Node = Queue.top().second;
1229 if (!Node->State.NextToken) {
1230 LLVM_DEBUG(llvm::dbgs()
1231 << "\n---\nPenalty for line: " << Penalty << "\n");
1232 break;
1233 }
1234 Queue.pop();
1235
1236 // Cut off the analysis of certain solutions if the analysis gets too
1237 // complex. See description of IgnoreStackForComparison.
1238 if (Count > 50000)
1239 Node->State.IgnoreStackForComparison = true;
1240
1241 if (!Seen.insert(&Node->State).second) {
1242 // State already examined with lower penalty.
1243 continue;
1244 }
1245
1246 FormatDecision LastFormat = Node->State.NextToken->getDecision();
1247 if (LastFormat == FD_Unformatted || LastFormat == FD_Continue)
1248 addNextStateToQueue(Penalty, Node, /*NewLine=*/false, &Count, &Queue);
1249 if (LastFormat == FD_Unformatted || LastFormat == FD_Break)
1250 addNextStateToQueue(Penalty, Node, /*NewLine=*/true, &Count, &Queue);
1251 }
1252
1253 if (Queue.empty()) {
1254 // We were unable to find a solution, do nothing.
1255 // FIXME: Add diagnostic?
1256 LLVM_DEBUG(llvm::dbgs() << "Could not find a solution.\n");
1257 return 0;
1258 }
1259
1260 // Reconstruct the solution.
1261 if (!DryRun)
1262 reconstructPath(InitialState, Queue.top().second);
1263
1264 LLVM_DEBUG(llvm::dbgs()
1265 << "Total number of analyzed states: " << Count << "\n");
1266 LLVM_DEBUG(llvm::dbgs() << "---\n");
1267
1268 return Penalty;
1269 }
1270
1271 /// Add the following state to the analysis queue \c Queue.
1272 ///
1273 /// Assume the current state is \p PreviousNode and has been reached with a
1274 /// penalty of \p Penalty. Insert a line break if \p NewLine is \c true.
addNextStateToQueue(unsigned Penalty,StateNode * PreviousNode,bool NewLine,unsigned * Count,QueueType * Queue)1275 void addNextStateToQueue(unsigned Penalty, StateNode *PreviousNode,
1276 bool NewLine, unsigned *Count, QueueType *Queue) {
1277 if (NewLine && !Indenter->canBreak(PreviousNode->State))
1278 return;
1279 if (!NewLine && Indenter->mustBreak(PreviousNode->State))
1280 return;
1281
1282 StateNode *Node = new (Allocator.Allocate())
1283 StateNode(PreviousNode->State, NewLine, PreviousNode);
1284 if (!formatChildren(Node->State, NewLine, /*DryRun=*/true, Penalty))
1285 return;
1286
1287 Penalty += Indenter->addTokenToState(Node->State, NewLine, true);
1288
1289 Queue->push(QueueItem(OrderedPenalty(Penalty, *Count), Node));
1290 ++(*Count);
1291 }
1292
1293 /// Applies the best formatting by reconstructing the path in the
1294 /// solution space that leads to \c Best.
reconstructPath(LineState & State,StateNode * Best)1295 void reconstructPath(LineState &State, StateNode *Best) {
1296 llvm::SmallVector<StateNode *> Path;
1297 // We do not need a break before the initial token.
1298 while (Best->Previous) {
1299 Path.push_back(Best);
1300 Best = Best->Previous;
1301 }
1302 for (const auto &Node : llvm::reverse(Path)) {
1303 unsigned Penalty = 0;
1304 formatChildren(State, Node->NewLine, /*DryRun=*/false, Penalty);
1305 Penalty += Indenter->addTokenToState(State, Node->NewLine, false);
1306
1307 LLVM_DEBUG({
1308 printLineState(Node->Previous->State);
1309 if (Node->NewLine) {
1310 llvm::dbgs() << "Penalty for placing "
1311 << Node->Previous->State.NextToken->Tok.getName()
1312 << " on a new line: " << Penalty << "\n";
1313 }
1314 });
1315 }
1316 }
1317
1318 llvm::SpecificBumpPtrAllocator<StateNode> Allocator;
1319 };
1320
1321 } // anonymous namespace
1322
format(const SmallVectorImpl<AnnotatedLine * > & Lines,bool DryRun,int AdditionalIndent,bool FixBadIndentation,unsigned FirstStartColumn,unsigned NextStartColumn,unsigned LastStartColumn)1323 unsigned UnwrappedLineFormatter::format(
1324 const SmallVectorImpl<AnnotatedLine *> &Lines, bool DryRun,
1325 int AdditionalIndent, bool FixBadIndentation, unsigned FirstStartColumn,
1326 unsigned NextStartColumn, unsigned LastStartColumn) {
1327 LineJoiner Joiner(Style, Keywords, Lines);
1328
1329 // Try to look up already computed penalty in DryRun-mode.
1330 std::pair<const SmallVectorImpl<AnnotatedLine *> *, unsigned> CacheKey(
1331 &Lines, AdditionalIndent);
1332 auto CacheIt = PenaltyCache.find(CacheKey);
1333 if (DryRun && CacheIt != PenaltyCache.end())
1334 return CacheIt->second;
1335
1336 assert(!Lines.empty());
1337 unsigned Penalty = 0;
1338 LevelIndentTracker IndentTracker(Style, Keywords, Lines[0]->Level,
1339 AdditionalIndent);
1340 const AnnotatedLine *PrevPrevLine = nullptr;
1341 const AnnotatedLine *PreviousLine = nullptr;
1342 const AnnotatedLine *NextLine = nullptr;
1343
1344 // The minimum level of consecutive lines that have been formatted.
1345 unsigned RangeMinLevel = UINT_MAX;
1346
1347 bool FirstLine = true;
1348 for (const AnnotatedLine *Line =
1349 Joiner.getNextMergedLine(DryRun, IndentTracker);
1350 Line; PrevPrevLine = PreviousLine, PreviousLine = Line, Line = NextLine,
1351 FirstLine = false) {
1352 assert(Line->First);
1353 const AnnotatedLine &TheLine = *Line;
1354 unsigned Indent = IndentTracker.getIndent();
1355
1356 // We continue formatting unchanged lines to adjust their indent, e.g. if a
1357 // scope was added. However, we need to carefully stop doing this when we
1358 // exit the scope of affected lines to prevent indenting the entire
1359 // remaining file if it currently missing a closing brace.
1360 bool PreviousRBrace =
1361 PreviousLine && PreviousLine->startsWith(tok::r_brace);
1362 bool ContinueFormatting =
1363 TheLine.Level > RangeMinLevel ||
1364 (TheLine.Level == RangeMinLevel && !PreviousRBrace &&
1365 !TheLine.startsWith(tok::r_brace));
1366
1367 bool FixIndentation = (FixBadIndentation || ContinueFormatting) &&
1368 Indent != TheLine.First->OriginalColumn;
1369 bool ShouldFormat = TheLine.Affected || FixIndentation;
1370 // We cannot format this line; if the reason is that the line had a
1371 // parsing error, remember that.
1372 if (ShouldFormat && TheLine.Type == LT_Invalid && Status) {
1373 Status->FormatComplete = false;
1374 Status->Line =
1375 SourceMgr.getSpellingLineNumber(TheLine.First->Tok.getLocation());
1376 }
1377
1378 if (ShouldFormat && TheLine.Type != LT_Invalid) {
1379 if (!DryRun) {
1380 bool LastLine = TheLine.First->is(tok::eof);
1381 formatFirstToken(TheLine, PreviousLine, PrevPrevLine, Lines, Indent,
1382 LastLine ? LastStartColumn : NextStartColumn + Indent);
1383 }
1384
1385 NextLine = Joiner.getNextMergedLine(DryRun, IndentTracker);
1386 unsigned ColumnLimit = getColumnLimit(TheLine.InPPDirective, NextLine);
1387 bool FitsIntoOneLine =
1388 !TheLine.ContainsMacroCall &&
1389 (TheLine.Last->TotalLength + Indent <= ColumnLimit ||
1390 (TheLine.Type == LT_ImportStatement &&
1391 (!Style.isJavaScript() || !Style.JavaScriptWrapImports)) ||
1392 (Style.isCSharp() &&
1393 TheLine.InPPDirective)); // don't split #regions in C#
1394 if (Style.ColumnLimit == 0) {
1395 NoColumnLimitLineFormatter(Indenter, Whitespaces, Style, this)
1396 .formatLine(TheLine, NextStartColumn + Indent,
1397 FirstLine ? FirstStartColumn : 0, DryRun);
1398 } else if (FitsIntoOneLine) {
1399 Penalty += NoLineBreakFormatter(Indenter, Whitespaces, Style, this)
1400 .formatLine(TheLine, NextStartColumn + Indent,
1401 FirstLine ? FirstStartColumn : 0, DryRun);
1402 } else {
1403 Penalty += OptimizingLineFormatter(Indenter, Whitespaces, Style, this)
1404 .formatLine(TheLine, NextStartColumn + Indent,
1405 FirstLine ? FirstStartColumn : 0, DryRun);
1406 }
1407 RangeMinLevel = std::min(RangeMinLevel, TheLine.Level);
1408 } else {
1409 // If no token in the current line is affected, we still need to format
1410 // affected children.
1411 if (TheLine.ChildrenAffected) {
1412 for (const FormatToken *Tok = TheLine.First; Tok; Tok = Tok->Next)
1413 if (!Tok->Children.empty())
1414 format(Tok->Children, DryRun);
1415 }
1416
1417 // Adapt following lines on the current indent level to the same level
1418 // unless the current \c AnnotatedLine is not at the beginning of a line.
1419 bool StartsNewLine =
1420 TheLine.First->NewlinesBefore > 0 || TheLine.First->IsFirst;
1421 if (StartsNewLine)
1422 IndentTracker.adjustToUnmodifiedLine(TheLine);
1423 if (!DryRun) {
1424 bool ReformatLeadingWhitespace =
1425 StartsNewLine && ((PreviousLine && PreviousLine->Affected) ||
1426 TheLine.LeadingEmptyLinesAffected);
1427 // Format the first token.
1428 if (ReformatLeadingWhitespace) {
1429 formatFirstToken(TheLine, PreviousLine, PrevPrevLine, Lines,
1430 TheLine.First->OriginalColumn,
1431 TheLine.First->OriginalColumn);
1432 } else {
1433 Whitespaces->addUntouchableToken(*TheLine.First,
1434 TheLine.InPPDirective);
1435 }
1436
1437 // Notify the WhitespaceManager about the unchanged whitespace.
1438 for (FormatToken *Tok = TheLine.First->Next; Tok; Tok = Tok->Next)
1439 Whitespaces->addUntouchableToken(*Tok, TheLine.InPPDirective);
1440 }
1441 NextLine = Joiner.getNextMergedLine(DryRun, IndentTracker);
1442 RangeMinLevel = UINT_MAX;
1443 }
1444 if (!DryRun)
1445 markFinalized(TheLine.First);
1446 }
1447 PenaltyCache[CacheKey] = Penalty;
1448 return Penalty;
1449 }
1450
computeNewlines(const AnnotatedLine & Line,const AnnotatedLine * PreviousLine,const AnnotatedLine * PrevPrevLine,const SmallVectorImpl<AnnotatedLine * > & Lines,const FormatStyle & Style)1451 static auto computeNewlines(const AnnotatedLine &Line,
1452 const AnnotatedLine *PreviousLine,
1453 const AnnotatedLine *PrevPrevLine,
1454 const SmallVectorImpl<AnnotatedLine *> &Lines,
1455 const FormatStyle &Style) {
1456 const auto &RootToken = *Line.First;
1457 auto Newlines =
1458 std::min(RootToken.NewlinesBefore, Style.MaxEmptyLinesToKeep + 1);
1459 // Remove empty lines before "}" where applicable.
1460 if (RootToken.is(tok::r_brace) &&
1461 (!RootToken.Next ||
1462 (RootToken.Next->is(tok::semi) && !RootToken.Next->Next)) &&
1463 // Do not remove empty lines before namespace closing "}".
1464 !getNamespaceToken(&Line, Lines)) {
1465 Newlines = std::min(Newlines, 1u);
1466 }
1467 // Remove empty lines at the start of nested blocks (lambdas/arrow functions)
1468 if (!PreviousLine && Line.Level > 0)
1469 Newlines = std::min(Newlines, 1u);
1470 if (Newlines == 0 && !RootToken.IsFirst)
1471 Newlines = 1;
1472 if (RootToken.IsFirst && !RootToken.HasUnescapedNewline)
1473 Newlines = 0;
1474
1475 // Remove empty lines after "{".
1476 if (!Style.KeepEmptyLinesAtTheStartOfBlocks && PreviousLine &&
1477 PreviousLine->Last->is(tok::l_brace) &&
1478 !PreviousLine->startsWithNamespace() &&
1479 !(PrevPrevLine && PrevPrevLine->startsWithNamespace() &&
1480 PreviousLine->startsWith(tok::l_brace)) &&
1481 !startsExternCBlock(*PreviousLine)) {
1482 Newlines = 1;
1483 }
1484
1485 // Insert or remove empty line before access specifiers.
1486 if (PreviousLine && RootToken.isAccessSpecifier()) {
1487 switch (Style.EmptyLineBeforeAccessModifier) {
1488 case FormatStyle::ELBAMS_Never:
1489 if (Newlines > 1)
1490 Newlines = 1;
1491 break;
1492 case FormatStyle::ELBAMS_Leave:
1493 Newlines = std::max(RootToken.NewlinesBefore, 1u);
1494 break;
1495 case FormatStyle::ELBAMS_LogicalBlock:
1496 if (PreviousLine->Last->isOneOf(tok::semi, tok::r_brace) && Newlines <= 1)
1497 Newlines = 2;
1498 if (PreviousLine->First->isAccessSpecifier())
1499 Newlines = 1; // Previous is an access modifier remove all new lines.
1500 break;
1501 case FormatStyle::ELBAMS_Always: {
1502 const FormatToken *previousToken;
1503 if (PreviousLine->Last->is(tok::comment))
1504 previousToken = PreviousLine->Last->getPreviousNonComment();
1505 else
1506 previousToken = PreviousLine->Last;
1507 if ((!previousToken || previousToken->isNot(tok::l_brace)) &&
1508 Newlines <= 1) {
1509 Newlines = 2;
1510 }
1511 } break;
1512 }
1513 }
1514
1515 // Insert or remove empty line after access specifiers.
1516 if (PreviousLine && PreviousLine->First->isAccessSpecifier() &&
1517 (!PreviousLine->InPPDirective || !RootToken.HasUnescapedNewline)) {
1518 // EmptyLineBeforeAccessModifier is handling the case when two access
1519 // modifiers follow each other.
1520 if (!RootToken.isAccessSpecifier()) {
1521 switch (Style.EmptyLineAfterAccessModifier) {
1522 case FormatStyle::ELAAMS_Never:
1523 Newlines = 1;
1524 break;
1525 case FormatStyle::ELAAMS_Leave:
1526 Newlines = std::max(Newlines, 1u);
1527 break;
1528 case FormatStyle::ELAAMS_Always:
1529 if (RootToken.is(tok::r_brace)) // Do not add at end of class.
1530 Newlines = 1u;
1531 else
1532 Newlines = std::max(Newlines, 2u);
1533 break;
1534 }
1535 }
1536 }
1537
1538 return Newlines;
1539 }
1540
formatFirstToken(const AnnotatedLine & Line,const AnnotatedLine * PreviousLine,const AnnotatedLine * PrevPrevLine,const SmallVectorImpl<AnnotatedLine * > & Lines,unsigned Indent,unsigned NewlineIndent)1541 void UnwrappedLineFormatter::formatFirstToken(
1542 const AnnotatedLine &Line, const AnnotatedLine *PreviousLine,
1543 const AnnotatedLine *PrevPrevLine,
1544 const SmallVectorImpl<AnnotatedLine *> &Lines, unsigned Indent,
1545 unsigned NewlineIndent) {
1546 FormatToken &RootToken = *Line.First;
1547 if (RootToken.is(tok::eof)) {
1548 unsigned Newlines =
1549 std::min(RootToken.NewlinesBefore,
1550 Style.KeepEmptyLinesAtEOF ? Style.MaxEmptyLinesToKeep + 1 : 1);
1551 unsigned TokenIndent = Newlines ? NewlineIndent : 0;
1552 Whitespaces->replaceWhitespace(RootToken, Newlines, TokenIndent,
1553 TokenIndent);
1554 return;
1555 }
1556
1557 if (RootToken.Newlines < 0) {
1558 RootToken.Newlines =
1559 computeNewlines(Line, PreviousLine, PrevPrevLine, Lines, Style);
1560 assert(RootToken.Newlines >= 0);
1561 }
1562
1563 if (RootToken.Newlines > 0)
1564 Indent = NewlineIndent;
1565
1566 // Preprocessor directives get indented before the hash only if specified. In
1567 // Javascript import statements are indented like normal statements.
1568 if (!Style.isJavaScript() &&
1569 Style.IndentPPDirectives != FormatStyle::PPDIS_BeforeHash &&
1570 (Line.Type == LT_PreprocessorDirective ||
1571 Line.Type == LT_ImportStatement)) {
1572 Indent = 0;
1573 }
1574
1575 Whitespaces->replaceWhitespace(RootToken, RootToken.Newlines, Indent, Indent,
1576 /*IsAligned=*/false,
1577 Line.InPPDirective &&
1578 !RootToken.HasUnescapedNewline);
1579 }
1580
1581 unsigned
getColumnLimit(bool InPPDirective,const AnnotatedLine * NextLine) const1582 UnwrappedLineFormatter::getColumnLimit(bool InPPDirective,
1583 const AnnotatedLine *NextLine) const {
1584 // In preprocessor directives reserve two chars for trailing " \" if the
1585 // next line continues the preprocessor directive.
1586 bool ContinuesPPDirective =
1587 InPPDirective &&
1588 // If there is no next line, this is likely a child line and the parent
1589 // continues the preprocessor directive.
1590 (!NextLine ||
1591 (NextLine->InPPDirective &&
1592 // If there is an unescaped newline between this line and the next, the
1593 // next line starts a new preprocessor directive.
1594 !NextLine->First->HasUnescapedNewline));
1595 return Style.ColumnLimit - (ContinuesPPDirective ? 2 : 0);
1596 }
1597
1598 } // namespace format
1599 } // namespace clang
1600