| //===--- UnwrappedLineFormatter.cpp - Format C++ code ---------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "UnwrappedLineFormatter.h" |
| #include "FormatToken.h" |
| #include "NamespaceEndCommentsFixer.h" |
| #include "WhitespaceManager.h" |
| #include "llvm/Support/Debug.h" |
| #include <queue> |
| |
| #define DEBUG_TYPE "format-formatter" |
| |
| namespace clang { |
| namespace format { |
| |
| namespace { |
| |
| bool startsExternCBlock(const AnnotatedLine &Line) { |
| const FormatToken *Next = Line.First->getNextNonComment(); |
| const FormatToken *NextNext = Next ? Next->getNextNonComment() : nullptr; |
| return Line.startsWith(tok::kw_extern) && Next && Next->isStringLiteral() && |
| NextNext && NextNext->is(tok::l_brace); |
| } |
| |
| bool isRecordLBrace(const FormatToken &Tok) { |
| return Tok.isOneOf(TT_ClassLBrace, TT_EnumLBrace, TT_RecordLBrace, |
| TT_StructLBrace, TT_UnionLBrace); |
| } |
| |
| /// Tracks the indent level of \c AnnotatedLines across levels. |
| /// |
| /// \c nextLine must be called for each \c AnnotatedLine, after which \c |
| /// getIndent() will return the indent for the last line \c nextLine was called |
| /// with. |
| /// If the line is not formatted (and thus the indent does not change), calling |
| /// \c adjustToUnmodifiedLine after the call to \c nextLine will cause |
| /// subsequent lines on the same level to be indented at the same level as the |
| /// given line. |
| class LevelIndentTracker { |
| public: |
| LevelIndentTracker(const FormatStyle &Style, |
| const AdditionalKeywords &Keywords, unsigned StartLevel, |
| int AdditionalIndent) |
| : Style(Style), Keywords(Keywords), AdditionalIndent(AdditionalIndent) { |
| for (unsigned i = 0; i != StartLevel; ++i) |
| IndentForLevel.push_back(Style.IndentWidth * i + AdditionalIndent); |
| } |
| |
| /// Returns the indent for the current line. |
| unsigned getIndent() const { return Indent; } |
| |
| /// Update the indent state given that \p Line is going to be formatted |
| /// next. |
| void nextLine(const AnnotatedLine &Line) { |
| Offset = getIndentOffset(*Line.First); |
| // Update the indent level cache size so that we can rely on it |
| // having the right size in adjustToUnmodifiedline. |
| if (Line.Level >= IndentForLevel.size()) |
| IndentForLevel.resize(Line.Level + 1, -1); |
| if (Style.IndentPPDirectives != FormatStyle::PPDIS_None && |
| (Line.InPPDirective || |
| (Style.IndentPPDirectives == FormatStyle::PPDIS_BeforeHash && |
| Line.Type == LT_CommentAbovePPDirective))) { |
| unsigned PPIndentWidth = |
| (Style.PPIndentWidth >= 0) ? Style.PPIndentWidth : Style.IndentWidth; |
| Indent = Line.InMacroBody |
| ? Line.PPLevel * PPIndentWidth + |
| (Line.Level - Line.PPLevel) * Style.IndentWidth |
| : Line.Level * PPIndentWidth; |
| Indent += AdditionalIndent; |
| } else { |
| // When going to lower levels, forget previous higher levels so that we |
| // recompute future higher levels. But don't forget them if we enter a PP |
| // directive, since these do not terminate a C++ code block. |
| if (!Line.InPPDirective) { |
| assert(Line.Level <= IndentForLevel.size()); |
| IndentForLevel.resize(Line.Level + 1); |
| } |
| Indent = getIndent(Line.Level); |
| } |
| if (static_cast<int>(Indent) + Offset >= 0) |
| Indent += Offset; |
| if (Line.IsContinuation) |
| Indent = Line.Level * Style.IndentWidth + Style.ContinuationIndentWidth; |
| } |
| |
| /// Update the level indent to adapt to the given \p Line. |
| /// |
| /// When a line is not formatted, we move the subsequent lines on the same |
| /// level to the same indent. |
| /// Note that \c nextLine must have been called before this method. |
| void adjustToUnmodifiedLine(const AnnotatedLine &Line) { |
| if (Line.InPPDirective || Line.IsContinuation) |
| return; |
| assert(Line.Level < IndentForLevel.size()); |
| if (Line.First->is(tok::comment) && IndentForLevel[Line.Level] != -1) |
| return; |
| unsigned LevelIndent = Line.First->OriginalColumn; |
| if (static_cast<int>(LevelIndent) - Offset >= 0) |
| LevelIndent -= Offset; |
| IndentForLevel[Line.Level] = LevelIndent; |
| } |
| |
| private: |
| /// Get the offset of the line relatively to the level. |
| /// |
| /// For example, 'public:' labels in classes are offset by 1 or 2 |
| /// characters to the left from their level. |
| int getIndentOffset(const FormatToken &RootToken) { |
| if (Style.Language == FormatStyle::LK_Java || Style.isJavaScript() || |
| Style.isCSharp()) { |
| return 0; |
| } |
| |
| auto IsAccessModifier = [this, &RootToken]() { |
| if (RootToken.isAccessSpecifier(Style.isCpp())) { |
| return true; |
| } else if (RootToken.isObjCAccessSpecifier()) { |
| return true; |
| } |
| // Handle Qt signals. |
| else if (RootToken.isOneOf(Keywords.kw_signals, Keywords.kw_qsignals) && |
| RootToken.Next && RootToken.Next->is(tok::colon)) { |
| return true; |
| } else if (RootToken.Next && |
| RootToken.Next->isOneOf(Keywords.kw_slots, |
| Keywords.kw_qslots) && |
| RootToken.Next->Next && RootToken.Next->Next->is(tok::colon)) { |
| return true; |
| } |
| // Handle malformed access specifier e.g. 'private' without trailing ':'. |
| else if (!RootToken.Next && RootToken.isAccessSpecifier(false)) { |
| return true; |
| } |
| return false; |
| }; |
| |
| if (IsAccessModifier()) { |
| // The AccessModifierOffset may be overridden by IndentAccessModifiers, |
| // in which case we take a negative value of the IndentWidth to simulate |
| // the upper indent level. |
| return Style.IndentAccessModifiers ? -Style.IndentWidth |
| : Style.AccessModifierOffset; |
| } |
| return 0; |
| } |
| |
| /// Get the indent of \p Level from \p IndentForLevel. |
| /// |
| /// \p IndentForLevel must contain the indent for the level \c l |
| /// at \p IndentForLevel[l], or a value < 0 if the indent for |
| /// that level is unknown. |
| unsigned getIndent(unsigned Level) const { |
| assert(Level < IndentForLevel.size()); |
| if (IndentForLevel[Level] != -1) |
| return IndentForLevel[Level]; |
| if (Level == 0) |
| return 0; |
| return getIndent(Level - 1) + Style.IndentWidth; |
| } |
| |
| const FormatStyle &Style; |
| const AdditionalKeywords &Keywords; |
| const unsigned AdditionalIndent; |
| |
| /// The indent in characters for each level. It remembers the indent of |
| /// previous lines (that are not PP directives) of equal or lower levels. This |
| /// is used to align formatted lines to the indent of previous non-formatted |
| /// lines. Think about the --lines parameter of clang-format. |
| SmallVector<int> IndentForLevel; |
| |
| /// Offset of the current line relative to the indent level. |
| /// |
| /// For example, the 'public' keywords is often indented with a negative |
| /// offset. |
| int Offset = 0; |
| |
| /// The current line's indent. |
| unsigned Indent = 0; |
| }; |
| |
| const FormatToken *getMatchingNamespaceToken( |
| const AnnotatedLine *Line, |
| const SmallVectorImpl<AnnotatedLine *> &AnnotatedLines) { |
| if (!Line->startsWith(tok::r_brace)) |
| return nullptr; |
| size_t StartLineIndex = Line->MatchingOpeningBlockLineIndex; |
| if (StartLineIndex == UnwrappedLine::kInvalidIndex) |
| return nullptr; |
| assert(StartLineIndex < AnnotatedLines.size()); |
| return AnnotatedLines[StartLineIndex]->First->getNamespaceToken(); |
| } |
| |
| StringRef getNamespaceTokenText(const AnnotatedLine *Line) { |
| const FormatToken *NamespaceToken = Line->First->getNamespaceToken(); |
| return NamespaceToken ? NamespaceToken->TokenText : StringRef(); |
| } |
| |
| StringRef getMatchingNamespaceTokenText( |
| const AnnotatedLine *Line, |
| const SmallVectorImpl<AnnotatedLine *> &AnnotatedLines) { |
| const FormatToken *NamespaceToken = |
| getMatchingNamespaceToken(Line, AnnotatedLines); |
| return NamespaceToken ? NamespaceToken->TokenText : StringRef(); |
| } |
| |
| class LineJoiner { |
| public: |
| LineJoiner(const FormatStyle &Style, const AdditionalKeywords &Keywords, |
| const SmallVectorImpl<AnnotatedLine *> &Lines) |
| : Style(Style), Keywords(Keywords), End(Lines.end()), Next(Lines.begin()), |
| AnnotatedLines(Lines) {} |
| |
| /// Returns the next line, merging multiple lines into one if possible. |
| const AnnotatedLine *getNextMergedLine(bool DryRun, |
| LevelIndentTracker &IndentTracker) { |
| if (Next == End) |
| return nullptr; |
| const AnnotatedLine *Current = *Next; |
| IndentTracker.nextLine(*Current); |
| unsigned MergedLines = tryFitMultipleLinesInOne(IndentTracker, Next, End); |
| if (MergedLines > 0 && Style.ColumnLimit == 0) { |
| // Disallow line merging if there is a break at the start of one of the |
| // input lines. |
| for (unsigned i = 0; i < MergedLines; ++i) |
| if (Next[i + 1]->First->NewlinesBefore > 0) |
| MergedLines = 0; |
| } |
| if (!DryRun) |
| for (unsigned i = 0; i < MergedLines; ++i) |
| join(*Next[0], *Next[i + 1]); |
| Next = Next + MergedLines + 1; |
| return Current; |
| } |
| |
| private: |
| /// Calculates how many lines can be merged into 1 starting at \p I. |
| unsigned |
| tryFitMultipleLinesInOne(LevelIndentTracker &IndentTracker, |
| SmallVectorImpl<AnnotatedLine *>::const_iterator I, |
| SmallVectorImpl<AnnotatedLine *>::const_iterator E) { |
| const unsigned Indent = IndentTracker.getIndent(); |
| |
| // Can't join the last line with anything. |
| if (I + 1 == E) |
| return 0; |
| // We can never merge stuff if there are trailing line comments. |
| const AnnotatedLine *TheLine = *I; |
| if (TheLine->Last->is(TT_LineComment)) |
| return 0; |
| const auto &NextLine = *I[1]; |
| if (NextLine.Type == LT_Invalid || NextLine.First->MustBreakBefore) |
| return 0; |
| if (TheLine->InPPDirective && |
| (!NextLine.InPPDirective || NextLine.First->HasUnescapedNewline)) { |
| return 0; |
| } |
| |
| if (Style.ColumnLimit > 0 && Indent > Style.ColumnLimit) |
| return 0; |
| |
| unsigned Limit = |
| Style.ColumnLimit == 0 ? UINT_MAX : Style.ColumnLimit - Indent; |
| // If we already exceed the column limit, we set 'Limit' to 0. The different |
| // tryMerge..() functions can then decide whether to still do merging. |
| Limit = TheLine->Last->TotalLength > Limit |
| ? 0 |
| : Limit - TheLine->Last->TotalLength; |
| |
| if (TheLine->Last->is(TT_FunctionLBrace) && |
| TheLine->First == TheLine->Last && |
| !Style.BraceWrapping.SplitEmptyFunction && |
| NextLine.First->is(tok::r_brace)) { |
| return tryMergeSimpleBlock(I, E, Limit); |
| } |
| |
| const auto *PreviousLine = I != AnnotatedLines.begin() ? I[-1] : nullptr; |
| // Handle empty record blocks where the brace has already been wrapped. |
| if (PreviousLine && TheLine->Last->is(tok::l_brace) && |
| TheLine->First == TheLine->Last) { |
| bool EmptyBlock = NextLine.First->is(tok::r_brace); |
| |
| const FormatToken *Tok = PreviousLine->First; |
| if (Tok && Tok->is(tok::comment)) |
| Tok = Tok->getNextNonComment(); |
| |
| if (Tok && Tok->getNamespaceToken()) { |
| return !Style.BraceWrapping.SplitEmptyNamespace && EmptyBlock |
| ? tryMergeSimpleBlock(I, E, Limit) |
| : 0; |
| } |
| |
| if (Tok && Tok->is(tok::kw_typedef)) |
| Tok = Tok->getNextNonComment(); |
| if (Tok && Tok->isOneOf(tok::kw_class, tok::kw_struct, tok::kw_union, |
| tok::kw_extern, Keywords.kw_interface)) { |
| return !Style.BraceWrapping.SplitEmptyRecord && EmptyBlock |
| ? tryMergeSimpleBlock(I, E, Limit) |
| : 0; |
| } |
| |
| if (Tok && Tok->is(tok::kw_template) && |
| Style.BraceWrapping.SplitEmptyRecord && EmptyBlock) { |
| return 0; |
| } |
| } |
| |
| auto ShouldMergeShortFunctions = [this, &I, &NextLine, PreviousLine, |
| TheLine]() { |
| if (Style.AllowShortFunctionsOnASingleLine == FormatStyle::SFS_All) |
| return true; |
| if (Style.AllowShortFunctionsOnASingleLine >= FormatStyle::SFS_Empty && |
| NextLine.First->is(tok::r_brace)) { |
| return true; |
| } |
| |
| if (Style.AllowShortFunctionsOnASingleLine & |
| FormatStyle::SFS_InlineOnly) { |
| // Just checking TheLine->Level != 0 is not enough, because it |
| // provokes treating functions inside indented namespaces as short. |
| if (Style.isJavaScript() && TheLine->Last->is(TT_FunctionLBrace)) |
| return true; |
| |
| if (TheLine->Level != 0) { |
| if (!PreviousLine) |
| return false; |
| |
| // TODO: Use IndentTracker to avoid loop? |
| // Find the last line with lower level. |
| const AnnotatedLine *Line = nullptr; |
| for (auto J = I - 1; J >= AnnotatedLines.begin(); --J) { |
| assert(*J); |
| if (!(*J)->InPPDirective && !(*J)->isComment() && |
| (*J)->Level < TheLine->Level) { |
| Line = *J; |
| break; |
| } |
| } |
| |
| if (!Line) |
| return false; |
| |
| // Check if the found line starts a record. |
| const auto *LastNonComment = Line->getLastNonComment(); |
| // There must be another token (usually `{`), because we chose a |
| // non-PPDirective and non-comment line that has a smaller level. |
| assert(LastNonComment); |
| return isRecordLBrace(*LastNonComment); |
| } |
| } |
| |
| return false; |
| }; |
| |
| bool MergeShortFunctions = ShouldMergeShortFunctions(); |
| |
| const auto *FirstNonComment = TheLine->getFirstNonComment(); |
| if (!FirstNonComment) |
| return 0; |
| // FIXME: There are probably cases where we should use FirstNonComment |
| // instead of TheLine->First. |
| |
| if (Style.CompactNamespaces) { |
| if (const auto *NSToken = TheLine->First->getNamespaceToken()) { |
| int J = 1; |
| assert(TheLine->MatchingClosingBlockLineIndex > 0); |
| for (auto ClosingLineIndex = TheLine->MatchingClosingBlockLineIndex - 1; |
| I + J != E && NSToken->TokenText == getNamespaceTokenText(I[J]) && |
| ClosingLineIndex == I[J]->MatchingClosingBlockLineIndex && |
| I[J]->Last->TotalLength < Limit; |
| ++J, --ClosingLineIndex) { |
| Limit -= I[J]->Last->TotalLength; |
| |
| // Reduce indent level for bodies of namespaces which were compacted, |
| // but only if their content was indented in the first place. |
| auto *ClosingLine = AnnotatedLines.begin() + ClosingLineIndex + 1; |
| const int OutdentBy = I[J]->Level - TheLine->Level; |
| assert(OutdentBy >= 0); |
| for (auto *CompactedLine = I + J; CompactedLine <= ClosingLine; |
| ++CompactedLine) { |
| if (!(*CompactedLine)->InPPDirective) { |
| const int Level = (*CompactedLine)->Level; |
| (*CompactedLine)->Level = std::max(Level - OutdentBy, 0); |
| } |
| } |
| } |
| return J - 1; |
| } |
| |
| if (auto nsToken = getMatchingNamespaceToken(TheLine, AnnotatedLines)) { |
| int i = 0; |
| unsigned openingLine = TheLine->MatchingOpeningBlockLineIndex - 1; |
| for (; I + 1 + i != E && |
| nsToken->TokenText == |
| getMatchingNamespaceTokenText(I[i + 1], AnnotatedLines) && |
| openingLine == I[i + 1]->MatchingOpeningBlockLineIndex; |
| i++, --openingLine) { |
| // No space between consecutive braces. |
| I[i + 1]->First->SpacesRequiredBefore = |
| I[i]->Last->isNot(tok::r_brace); |
| |
| // Indent like the outer-most namespace. |
| IndentTracker.nextLine(*I[i + 1]); |
| } |
| return i; |
| } |
| } |
| |
| const auto *LastNonComment = TheLine->getLastNonComment(); |
| assert(LastNonComment); |
| // FIXME: There are probably cases where we should use LastNonComment |
| // instead of TheLine->Last. |
| |
| // Try to merge a function block with left brace unwrapped. |
| if (LastNonComment->is(TT_FunctionLBrace) && |
| TheLine->First != LastNonComment) { |
| return MergeShortFunctions ? tryMergeSimpleBlock(I, E, Limit) : 0; |
| } |
| // Try to merge a control statement block with left brace unwrapped. |
| if (TheLine->Last->is(tok::l_brace) && FirstNonComment != TheLine->Last && |
| FirstNonComment->isOneOf(tok::kw_if, tok::kw_while, tok::kw_for, |
| TT_ForEachMacro)) { |
| return Style.AllowShortBlocksOnASingleLine != FormatStyle::SBS_Never |
| ? tryMergeSimpleBlock(I, E, Limit) |
| : 0; |
| } |
| // Try to merge a control statement block with left brace wrapped. |
| if (NextLine.First->is(tok::l_brace)) { |
| if ((TheLine->First->isOneOf(tok::kw_if, tok::kw_else, tok::kw_while, |
| tok::kw_for, tok::kw_switch, tok::kw_try, |
| tok::kw_do, TT_ForEachMacro) || |
| (TheLine->First->is(tok::r_brace) && TheLine->First->Next && |
| TheLine->First->Next->isOneOf(tok::kw_else, tok::kw_catch))) && |
| Style.BraceWrapping.AfterControlStatement == |
| FormatStyle::BWACS_MultiLine) { |
| // If possible, merge the next line's wrapped left brace with the |
| // current line. Otherwise, leave it on the next line, as this is a |
| // multi-line control statement. |
| return (Style.ColumnLimit == 0 || TheLine->Level * Style.IndentWidth + |
| TheLine->Last->TotalLength <= |
| Style.ColumnLimit) |
| ? 1 |
| : 0; |
| } |
| if (TheLine->First->isOneOf(tok::kw_if, tok::kw_else, tok::kw_while, |
| tok::kw_for, TT_ForEachMacro)) { |
| return (Style.BraceWrapping.AfterControlStatement == |
| FormatStyle::BWACS_Always) |
| ? tryMergeSimpleBlock(I, E, Limit) |
| : 0; |
| } |
| if (TheLine->First->isOneOf(tok::kw_else, tok::kw_catch) && |
| Style.BraceWrapping.AfterControlStatement == |
| FormatStyle::BWACS_MultiLine) { |
| // This case if different from the upper BWACS_MultiLine processing |
| // in that a preceding r_brace is not on the same line as else/catch |
| // most likely because of BeforeElse/BeforeCatch set to true. |
| // If the line length doesn't fit ColumnLimit, leave l_brace on the |
| // next line to respect the BWACS_MultiLine. |
| return (Style.ColumnLimit == 0 || |
| TheLine->Last->TotalLength <= Style.ColumnLimit) |
| ? 1 |
| : 0; |
| } |
| } |
| if (PreviousLine && TheLine->First->is(tok::l_brace)) { |
| switch (PreviousLine->First->Tok.getKind()) { |
| case tok::at: |
| // Don't merge block with left brace wrapped after ObjC special blocks. |
| if (PreviousLine->First->Next) { |
| tok::ObjCKeywordKind kwId = |
| PreviousLine->First->Next->Tok.getObjCKeywordID(); |
| if (kwId == tok::objc_autoreleasepool || |
| kwId == tok::objc_synchronized) { |
| return 0; |
| } |
| } |
| break; |
| |
| case tok::kw_case: |
| case tok::kw_default: |
| // Don't merge block with left brace wrapped after case labels. |
| return 0; |
| |
| default: |
| break; |
| } |
| } |
| |
| // Don't merge an empty template class or struct if SplitEmptyRecords |
| // is defined. |
| if (PreviousLine && Style.BraceWrapping.SplitEmptyRecord && |
| TheLine->Last->is(tok::l_brace) && PreviousLine->Last) { |
| const FormatToken *Previous = PreviousLine->Last; |
| if (Previous) { |
| if (Previous->is(tok::comment)) |
| Previous = Previous->getPreviousNonComment(); |
| if (Previous) { |
| if (Previous->is(tok::greater) && !PreviousLine->InPPDirective) |
| return 0; |
| if (Previous->is(tok::identifier)) { |
| const FormatToken *PreviousPrevious = |
| Previous->getPreviousNonComment(); |
| if (PreviousPrevious && |
| PreviousPrevious->isOneOf(tok::kw_class, tok::kw_struct)) { |
| return 0; |
| } |
| } |
| } |
| } |
| } |
| |
| if (TheLine->Last->is(tok::l_brace)) { |
| bool ShouldMerge = false; |
| // Try to merge records. |
| if (TheLine->Last->is(TT_EnumLBrace)) { |
| ShouldMerge = Style.AllowShortEnumsOnASingleLine; |
| } else if (TheLine->Last->is(TT_RequiresExpressionLBrace)) { |
| ShouldMerge = Style.AllowShortCompoundRequirementOnASingleLine; |
| } else if (TheLine->Last->isOneOf(TT_ClassLBrace, TT_StructLBrace)) { |
| // NOTE: We use AfterClass (whereas AfterStruct exists) for both classes |
| // and structs, but it seems that wrapping is still handled correctly |
| // elsewhere. |
| ShouldMerge = !Style.BraceWrapping.AfterClass || |
| (NextLine.First->is(tok::r_brace) && |
| !Style.BraceWrapping.SplitEmptyRecord); |
| } else if (TheLine->InPPDirective || |
| !TheLine->First->isOneOf(tok::kw_class, tok::kw_enum, |
| tok::kw_struct)) { |
| // Try to merge a block with left brace unwrapped that wasn't yet |
| // covered. |
| ShouldMerge = !Style.BraceWrapping.AfterFunction || |
| (NextLine.First->is(tok::r_brace) && |
| !Style.BraceWrapping.SplitEmptyFunction); |
| } |
| return ShouldMerge ? tryMergeSimpleBlock(I, E, Limit) : 0; |
| } |
| |
| // Try to merge a function block with left brace wrapped. |
| if (NextLine.First->is(TT_FunctionLBrace) && |
| Style.BraceWrapping.AfterFunction) { |
| if (NextLine.Last->is(TT_LineComment)) |
| return 0; |
| |
| // Check for Limit <= 2 to account for the " {". |
| if (Limit <= 2 || (Style.ColumnLimit == 0 && containsMustBreak(TheLine))) |
| return 0; |
| Limit -= 2; |
| |
| unsigned MergedLines = 0; |
| if (MergeShortFunctions || |
| (Style.AllowShortFunctionsOnASingleLine >= FormatStyle::SFS_Empty && |
| NextLine.First == NextLine.Last && I + 2 != E && |
| I[2]->First->is(tok::r_brace))) { |
| MergedLines = tryMergeSimpleBlock(I + 1, E, Limit); |
| // If we managed to merge the block, count the function header, which is |
| // on a separate line. |
| if (MergedLines > 0) |
| ++MergedLines; |
| } |
| return MergedLines; |
| } |
| auto IsElseLine = [&TheLine]() -> bool { |
| const FormatToken *First = TheLine->First; |
| if (First->is(tok::kw_else)) |
| return true; |
| |
| return First->is(tok::r_brace) && First->Next && |
| First->Next->is(tok::kw_else); |
| }; |
| if (TheLine->First->is(tok::kw_if) || |
| (IsElseLine() && (Style.AllowShortIfStatementsOnASingleLine == |
| FormatStyle::SIS_AllIfsAndElse))) { |
| return Style.AllowShortIfStatementsOnASingleLine |
| ? tryMergeSimpleControlStatement(I, E, Limit) |
| : 0; |
| } |
| if (TheLine->First->isOneOf(tok::kw_for, tok::kw_while, tok::kw_do, |
| TT_ForEachMacro)) { |
| return Style.AllowShortLoopsOnASingleLine |
| ? tryMergeSimpleControlStatement(I, E, Limit) |
| : 0; |
| } |
| if (TheLine->First->isOneOf(tok::kw_case, tok::kw_default)) { |
| return Style.AllowShortCaseLabelsOnASingleLine |
| ? tryMergeShortCaseLabels(I, E, Limit) |
| : 0; |
| } |
| if (TheLine->InPPDirective && |
| (TheLine->First->HasUnescapedNewline || TheLine->First->IsFirst)) { |
| return tryMergeSimplePPDirective(I, E, Limit); |
| } |
| return 0; |
| } |
| |
| unsigned |
| tryMergeSimplePPDirective(SmallVectorImpl<AnnotatedLine *>::const_iterator I, |
| SmallVectorImpl<AnnotatedLine *>::const_iterator E, |
| unsigned Limit) { |
| if (Limit == 0) |
| return 0; |
| if (I + 2 != E && I[2]->InPPDirective && !I[2]->First->HasUnescapedNewline) |
| return 0; |
| if (1 + I[1]->Last->TotalLength > Limit) |
| return 0; |
| return 1; |
| } |
| |
| unsigned tryMergeSimpleControlStatement( |
| SmallVectorImpl<AnnotatedLine *>::const_iterator I, |
| SmallVectorImpl<AnnotatedLine *>::const_iterator E, unsigned Limit) { |
| if (Limit == 0) |
| return 0; |
| if (Style.BraceWrapping.AfterControlStatement == |
| FormatStyle::BWACS_Always && |
| I[1]->First->is(tok::l_brace) && |
| Style.AllowShortBlocksOnASingleLine == FormatStyle::SBS_Never) { |
| return 0; |
| } |
| if (I[1]->InPPDirective != (*I)->InPPDirective || |
| (I[1]->InPPDirective && I[1]->First->HasUnescapedNewline)) { |
| return 0; |
| } |
| Limit = limitConsideringMacros(I + 1, E, Limit); |
| AnnotatedLine &Line = **I; |
| if (Line.First->isNot(tok::kw_do) && Line.First->isNot(tok::kw_else) && |
| Line.Last->isNot(tok::kw_else) && Line.Last->isNot(tok::r_paren)) { |
| return 0; |
| } |
| // Only merge `do while` if `do` is the only statement on the line. |
| if (Line.First->is(tok::kw_do) && Line.Last->isNot(tok::kw_do)) |
| return 0; |
| if (1 + I[1]->Last->TotalLength > Limit) |
| return 0; |
| // Don't merge with loops, ifs, a single semicolon or a line comment. |
| if (I[1]->First->isOneOf(tok::semi, tok::kw_if, tok::kw_for, tok::kw_while, |
| TT_ForEachMacro, TT_LineComment)) { |
| return 0; |
| } |
| // Only inline simple if's (no nested if or else), unless specified |
| if (Style.AllowShortIfStatementsOnASingleLine == |
| FormatStyle::SIS_WithoutElse) { |
| if (I + 2 != E && Line.startsWith(tok::kw_if) && |
| I[2]->First->is(tok::kw_else)) { |
| return 0; |
| } |
| } |
| return 1; |
| } |
| |
| unsigned |
| tryMergeShortCaseLabels(SmallVectorImpl<AnnotatedLine *>::const_iterator I, |
| SmallVectorImpl<AnnotatedLine *>::const_iterator E, |
| unsigned Limit) { |
| if (Limit == 0 || I + 1 == E || |
| I[1]->First->isOneOf(tok::kw_case, tok::kw_default)) { |
| return 0; |
| } |
| if (I[0]->Last->is(tok::l_brace) || I[1]->First->is(tok::l_brace)) |
| return 0; |
| unsigned NumStmts = 0; |
| unsigned Length = 0; |
| bool EndsWithComment = false; |
| bool InPPDirective = I[0]->InPPDirective; |
| bool InMacroBody = I[0]->InMacroBody; |
| const unsigned Level = I[0]->Level; |
| for (; NumStmts < 3; ++NumStmts) { |
| if (I + 1 + NumStmts == E) |
| break; |
| const AnnotatedLine *Line = I[1 + NumStmts]; |
| if (Line->InPPDirective != InPPDirective) |
| break; |
| if (Line->InMacroBody != InMacroBody) |
| break; |
| if (Line->First->isOneOf(tok::kw_case, tok::kw_default, tok::r_brace)) |
| break; |
| if (Line->First->isOneOf(tok::kw_if, tok::kw_for, tok::kw_switch, |
| tok::kw_while) || |
| EndsWithComment) { |
| return 0; |
| } |
| if (Line->First->is(tok::comment)) { |
| if (Level != Line->Level) |
| return 0; |
| SmallVectorImpl<AnnotatedLine *>::const_iterator J = I + 2 + NumStmts; |
| for (; J != E; ++J) { |
| Line = *J; |
| if (Line->InPPDirective != InPPDirective) |
| break; |
| if (Line->First->isOneOf(tok::kw_case, tok::kw_default, tok::r_brace)) |
| break; |
| if (Line->First->isNot(tok::comment) || Level != Line->Level) |
| return 0; |
| } |
| break; |
| } |
| if (Line->Last->is(tok::comment)) |
| EndsWithComment = true; |
| Length += I[1 + NumStmts]->Last->TotalLength + 1; // 1 for the space. |
| } |
| if (NumStmts == 0 || NumStmts == 3 || Length > Limit) |
| return 0; |
| return NumStmts; |
| } |
| |
| unsigned |
| tryMergeSimpleBlock(SmallVectorImpl<AnnotatedLine *>::const_iterator I, |
| SmallVectorImpl<AnnotatedLine *>::const_iterator E, |
| unsigned Limit) { |
| // Don't merge with a preprocessor directive. |
| if (I[1]->Type == LT_PreprocessorDirective) |
| return 0; |
| |
| AnnotatedLine &Line = **I; |
| |
| // Don't merge ObjC @ keywords and methods. |
| // FIXME: If an option to allow short exception handling clauses on a single |
| // line is added, change this to not return for @try and friends. |
| if (Style.Language != FormatStyle::LK_Java && |
| Line.First->isOneOf(tok::at, tok::minus, tok::plus)) { |
| return 0; |
| } |
| |
| // Check that the current line allows merging. This depends on whether we |
| // are in a control flow statements as well as several style flags. |
| if (Line.First->is(tok::kw_case) || |
| (Line.First->Next && Line.First->Next->is(tok::kw_else))) { |
| return 0; |
| } |
| // default: in switch statement |
| if (Line.First->is(tok::kw_default)) { |
| const FormatToken *Tok = Line.First->getNextNonComment(); |
| if (Tok && Tok->is(tok::colon)) |
| return 0; |
| } |
| |
| auto IsCtrlStmt = [](const auto &Line) { |
| return Line.First->isOneOf(tok::kw_if, tok::kw_else, tok::kw_while, |
| tok::kw_do, tok::kw_for, TT_ForEachMacro); |
| }; |
| |
| const bool IsSplitBlock = |
| Style.AllowShortBlocksOnASingleLine == FormatStyle::SBS_Never || |
| (Style.AllowShortBlocksOnASingleLine == FormatStyle::SBS_Empty && |
| I[1]->First->isNot(tok::r_brace)); |
| |
| if (IsCtrlStmt(Line) || |
| Line.First->isOneOf(tok::kw_try, tok::kw___try, tok::kw_catch, |
| tok::kw___finally, tok::r_brace, |
| Keywords.kw___except)) { |
| if (IsSplitBlock) |
| return 0; |
| // Don't merge when we can't except the case when |
| // the control statement block is empty |
| if (!Style.AllowShortIfStatementsOnASingleLine && |
| Line.First->isOneOf(tok::kw_if, tok::kw_else) && |
| !Style.BraceWrapping.AfterControlStatement && |
| I[1]->First->isNot(tok::r_brace)) { |
| return 0; |
| } |
| if (!Style.AllowShortIfStatementsOnASingleLine && |
| Line.First->isOneOf(tok::kw_if, tok::kw_else) && |
| Style.BraceWrapping.AfterControlStatement == |
| FormatStyle::BWACS_Always && |
| I + 2 != E && I[2]->First->isNot(tok::r_brace)) { |
| return 0; |
| } |
| if (!Style.AllowShortLoopsOnASingleLine && |
| Line.First->isOneOf(tok::kw_while, tok::kw_do, tok::kw_for, |
| TT_ForEachMacro) && |
| !Style.BraceWrapping.AfterControlStatement && |
| I[1]->First->isNot(tok::r_brace)) { |
| return 0; |
| } |
| if (!Style.AllowShortLoopsOnASingleLine && |
| Line.First->isOneOf(tok::kw_while, tok::kw_do, tok::kw_for, |
| TT_ForEachMacro) && |
| Style.BraceWrapping.AfterControlStatement == |
| FormatStyle::BWACS_Always && |
| I + 2 != E && I[2]->First->isNot(tok::r_brace)) { |
| return 0; |
| } |
| // FIXME: Consider an option to allow short exception handling clauses on |
| // a single line. |
| // FIXME: This isn't covered by tests. |
| // FIXME: For catch, __except, __finally the first token on the line |
| // is '}', so this isn't correct here. |
| if (Line.First->isOneOf(tok::kw_try, tok::kw___try, tok::kw_catch, |
| Keywords.kw___except, tok::kw___finally)) { |
| return 0; |
| } |
| } |
| |
| if (const auto *LastNonComment = Line.getLastNonComment(); |
| LastNonComment && LastNonComment->is(tok::l_brace)) { |
| if (IsSplitBlock && Line.First == Line.Last && |
| I > AnnotatedLines.begin() && |
| (I[-1]->endsWith(tok::kw_else) || IsCtrlStmt(*I[-1]))) { |
| return 0; |
| } |
| FormatToken *Tok = I[1]->First; |
| auto ShouldMerge = [Tok]() { |
| if (Tok->isNot(tok::r_brace) || Tok->MustBreakBefore) |
| return false; |
| const FormatToken *Next = Tok->getNextNonComment(); |
| return !Next || Next->is(tok::semi); |
| }; |
| |
| if (ShouldMerge()) { |
| // We merge empty blocks even if the line exceeds the column limit. |
| Tok->SpacesRequiredBefore = |
| (Style.SpaceInEmptyBlock || Line.Last->is(tok::comment)) ? 1 : 0; |
| Tok->CanBreakBefore = true; |
| return 1; |
| } else if (Limit != 0 && !Line.startsWithNamespace() && |
| !startsExternCBlock(Line)) { |
| // We don't merge short records. |
| if (isRecordLBrace(*Line.Last)) |
| return 0; |
| |
| // Check that we still have three lines and they fit into the limit. |
| if (I + 2 == E || I[2]->Type == LT_Invalid) |
| return 0; |
| Limit = limitConsideringMacros(I + 2, E, Limit); |
| |
| if (!nextTwoLinesFitInto(I, Limit)) |
| return 0; |
| |
| // Second, check that the next line does not contain any braces - if it |
| // does, readability declines when putting it into a single line. |
| if (I[1]->Last->is(TT_LineComment)) |
| return 0; |
| do { |
| if (Tok->is(tok::l_brace) && Tok->isNot(BK_BracedInit)) |
| return 0; |
| Tok = Tok->Next; |
| } while (Tok); |
| |
| // Last, check that the third line starts with a closing brace. |
| Tok = I[2]->First; |
| if (Tok->isNot(tok::r_brace)) |
| return 0; |
| |
| // Don't merge "if (a) { .. } else {". |
| if (Tok->Next && Tok->Next->is(tok::kw_else)) |
| return 0; |
| |
| // Don't merge a trailing multi-line control statement block like: |
| // } else if (foo && |
| // bar) |
| // { <-- current Line |
| // baz(); |
| // } |
| if (Line.First == Line.Last && Line.First->isNot(TT_FunctionLBrace) && |
| Style.BraceWrapping.AfterControlStatement == |
| FormatStyle::BWACS_MultiLine) { |
| return 0; |
| } |
| |
| return 2; |
| } |
| } else if (I[1]->First->is(tok::l_brace)) { |
| if (I[1]->Last->is(TT_LineComment)) |
| return 0; |
| |
| // Check for Limit <= 2 to account for the " {". |
| if (Limit <= 2 || (Style.ColumnLimit == 0 && containsMustBreak(*I))) |
| return 0; |
| Limit -= 2; |
| unsigned MergedLines = 0; |
| if (Style.AllowShortBlocksOnASingleLine != FormatStyle::SBS_Never || |
| (I[1]->First == I[1]->Last && I + 2 != E && |
| I[2]->First->is(tok::r_brace))) { |
| MergedLines = tryMergeSimpleBlock(I + 1, E, Limit); |
| // If we managed to merge the block, count the statement header, which |
| // is on a separate line. |
| if (MergedLines > 0) |
| ++MergedLines; |
| } |
| return MergedLines; |
| } |
| return 0; |
| } |
| |
| /// Returns the modified column limit for \p I if it is inside a macro and |
| /// needs a trailing '\'. |
| unsigned |
| limitConsideringMacros(SmallVectorImpl<AnnotatedLine *>::const_iterator I, |
| SmallVectorImpl<AnnotatedLine *>::const_iterator E, |
| unsigned Limit) { |
| if (I[0]->InPPDirective && I + 1 != E && |
| !I[1]->First->HasUnescapedNewline && I[1]->First->isNot(tok::eof)) { |
| return Limit < 2 ? 0 : Limit - 2; |
| } |
| return Limit; |
| } |
| |
| bool nextTwoLinesFitInto(SmallVectorImpl<AnnotatedLine *>::const_iterator I, |
| unsigned Limit) { |
| if (I[1]->First->MustBreakBefore || I[2]->First->MustBreakBefore) |
| return false; |
| return 1 + I[1]->Last->TotalLength + 1 + I[2]->Last->TotalLength <= Limit; |
| } |
| |
| bool containsMustBreak(const AnnotatedLine *Line) { |
| assert(Line->First); |
| // Ignore the first token, because in this situation, it applies more to the |
| // last token of the previous line. |
| for (const FormatToken *Tok = Line->First->Next; Tok; Tok = Tok->Next) |
| if (Tok->MustBreakBefore) |
| return true; |
| return false; |
| } |
| |
| void join(AnnotatedLine &A, const AnnotatedLine &B) { |
| assert(!A.Last->Next); |
| assert(!B.First->Previous); |
| if (B.Affected) |
| A.Affected = true; |
| A.Last->Next = B.First; |
| B.First->Previous = A.Last; |
| B.First->CanBreakBefore = true; |
| unsigned LengthA = A.Last->TotalLength + B.First->SpacesRequiredBefore; |
| for (FormatToken *Tok = B.First; Tok; Tok = Tok->Next) { |
| Tok->TotalLength += LengthA; |
| A.Last = Tok; |
| } |
| } |
| |
| const FormatStyle &Style; |
| const AdditionalKeywords &Keywords; |
| const SmallVectorImpl<AnnotatedLine *>::const_iterator End; |
| |
| SmallVectorImpl<AnnotatedLine *>::const_iterator Next; |
| const SmallVectorImpl<AnnotatedLine *> &AnnotatedLines; |
| }; |
| |
| static void markFinalized(FormatToken *Tok) { |
| if (Tok->is(tok::hash) && !Tok->Previous && Tok->Next && |
| Tok->Next->isOneOf(tok::pp_if, tok::pp_ifdef, tok::pp_ifndef, |
| tok::pp_elif, tok::pp_elifdef, tok::pp_elifndef, |
| tok::pp_else, tok::pp_endif)) { |
| Tok = Tok->Next; |
| } |
| for (; Tok; Tok = Tok->Next) { |
| if (Tok->MacroCtx && Tok->MacroCtx->Role == MR_ExpandedArg) { |
| // In the first pass we format all macro arguments in the expanded token |
| // stream. Instead of finalizing the macro arguments, we mark that they |
| // will be modified as unexpanded arguments (as part of the macro call |
| // formatting) in the next pass. |
| Tok->MacroCtx->Role = MR_UnexpandedArg; |
| // Reset whether spaces or a line break are required before this token, as |
| // that is context dependent, and that context may change when formatting |
| // the macro call. For example, given M(x) -> 2 * x, and the macro call |
| // M(var), the token 'var' will have SpacesRequiredBefore = 1 after being |
| // formatted as part of the expanded macro, but SpacesRequiredBefore = 0 |
| // for its position within the macro call. |
| Tok->SpacesRequiredBefore = 0; |
| if (!Tok->MustBreakBeforeFinalized) |
| Tok->MustBreakBefore = 0; |
| } else { |
| Tok->Finalized = true; |
| } |
| } |
| } |
| |
| #ifndef NDEBUG |
| static void printLineState(const LineState &State) { |
| llvm::dbgs() << "State: "; |
| for (const ParenState &P : State.Stack) { |
| llvm::dbgs() << (P.Tok ? P.Tok->TokenText : "F") << "|" << P.Indent << "|" |
| << P.LastSpace << "|" << P.NestedBlockIndent << " "; |
| } |
| llvm::dbgs() << State.NextToken->TokenText << "\n"; |
| } |
| #endif |
| |
| /// Base class for classes that format one \c AnnotatedLine. |
| class LineFormatter { |
| public: |
| LineFormatter(ContinuationIndenter *Indenter, WhitespaceManager *Whitespaces, |
| const FormatStyle &Style, |
| UnwrappedLineFormatter *BlockFormatter) |
| : Indenter(Indenter), Whitespaces(Whitespaces), Style(Style), |
| BlockFormatter(BlockFormatter) {} |
| virtual ~LineFormatter() {} |
| |
| /// Formats an \c AnnotatedLine and returns the penalty. |
| /// |
| /// If \p DryRun is \c false, directly applies the changes. |
| virtual unsigned formatLine(const AnnotatedLine &Line, unsigned FirstIndent, |
| unsigned FirstStartColumn, bool DryRun) = 0; |
| |
| protected: |
| /// If the \p State's next token is an r_brace closing a nested block, |
| /// format the nested block before it. |
| /// |
| /// Returns \c true if all children could be placed successfully and adapts |
| /// \p Penalty as well as \p State. If \p DryRun is false, also directly |
| /// creates changes using \c Whitespaces. |
| /// |
| /// The crucial idea here is that children always get formatted upon |
| /// encountering the closing brace right after the nested block. Now, if we |
| /// are currently trying to keep the "}" on the same line (i.e. \p NewLine is |
| /// \c false), the entire block has to be kept on the same line (which is only |
| /// possible if it fits on the line, only contains a single statement, etc. |
| /// |
| /// If \p NewLine is true, we format the nested block on separate lines, i.e. |
| /// break after the "{", format all lines with correct indentation and the put |
| /// the closing "}" on yet another new line. |
| /// |
| /// This enables us to keep the simple structure of the |
| /// \c UnwrappedLineFormatter, where we only have two options for each token: |
| /// break or don't break. |
| bool formatChildren(LineState &State, bool NewLine, bool DryRun, |
| unsigned &Penalty) { |
| const FormatToken *LBrace = State.NextToken->getPreviousNonComment(); |
| bool HasLBrace = LBrace && LBrace->is(tok::l_brace) && LBrace->is(BK_Block); |
| FormatToken &Previous = *State.NextToken->Previous; |
| if (Previous.Children.size() == 0 || (!HasLBrace && !LBrace->MacroParent)) { |
| // The previous token does not open a block. Nothing to do. We don't |
| // assert so that we can simply call this function for all tokens. |
| return true; |
| } |
| |
| if (NewLine || Previous.MacroParent) { |
| const ParenState &P = State.Stack.back(); |
| |
| int AdditionalIndent = |
| P.Indent - Previous.Children[0]->Level * Style.IndentWidth; |
| Penalty += |
| BlockFormatter->format(Previous.Children, DryRun, AdditionalIndent, |
| /*FixBadIndentation=*/true); |
| return true; |
| } |
| |
| if (Previous.Children[0]->First->MustBreakBefore) |
| return false; |
| |
| // Cannot merge into one line if this line ends on a comment. |
| if (Previous.is(tok::comment)) |
| return false; |
| |
| // Cannot merge multiple statements into a single line. |
| if (Previous.Children.size() > 1) |
| return false; |
| |
| const AnnotatedLine *Child = Previous.Children[0]; |
| // We can't put the closing "}" on a line with a trailing comment. |
| if (Child->Last->isTrailingComment()) |
| return false; |
| |
| // If the child line exceeds the column limit, we wouldn't want to merge it. |
| // We add +2 for the trailing " }". |
| if (Style.ColumnLimit > 0 && |
| Child->Last->TotalLength + State.Column + 2 > Style.ColumnLimit) { |
| return false; |
| } |
| |
| if (!DryRun) { |
| Whitespaces->replaceWhitespace( |
| *Child->First, /*Newlines=*/0, /*Spaces=*/1, |
| /*StartOfTokenColumn=*/State.Column, /*IsAligned=*/false, |
| State.Line->InPPDirective); |
| } |
| Penalty += |
| formatLine(*Child, State.Column + 1, /*FirstStartColumn=*/0, DryRun); |
| if (!DryRun) |
| markFinalized(Child->First); |
| |
| State.Column += 1 + Child->Last->TotalLength; |
| return true; |
| } |
| |
| ContinuationIndenter *Indenter; |
| |
| private: |
| WhitespaceManager *Whitespaces; |
| const FormatStyle &Style; |
| UnwrappedLineFormatter *BlockFormatter; |
| }; |
| |
| /// Formatter that keeps the existing line breaks. |
| class NoColumnLimitLineFormatter : public LineFormatter { |
| public: |
| NoColumnLimitLineFormatter(ContinuationIndenter *Indenter, |
| WhitespaceManager *Whitespaces, |
| const FormatStyle &Style, |
| UnwrappedLineFormatter *BlockFormatter) |
| : LineFormatter(Indenter, Whitespaces, Style, BlockFormatter) {} |
| |
| /// Formats the line, simply keeping all of the input's line breaking |
| /// decisions. |
| unsigned formatLine(const AnnotatedLine &Line, unsigned FirstIndent, |
| unsigned FirstStartColumn, bool DryRun) override { |
| assert(!DryRun); |
| LineState State = Indenter->getInitialState(FirstIndent, FirstStartColumn, |
| &Line, /*DryRun=*/false); |
| while (State.NextToken) { |
| bool Newline = |
| Indenter->mustBreak(State) || |
| (Indenter->canBreak(State) && State.NextToken->NewlinesBefore > 0); |
| unsigned Penalty = 0; |
| formatChildren(State, Newline, /*DryRun=*/false, Penalty); |
| Indenter->addTokenToState(State, Newline, /*DryRun=*/false); |
| } |
| return 0; |
| } |
| }; |
| |
| /// Formatter that puts all tokens into a single line without breaks. |
| class NoLineBreakFormatter : public LineFormatter { |
| public: |
| NoLineBreakFormatter(ContinuationIndenter *Indenter, |
| WhitespaceManager *Whitespaces, const FormatStyle &Style, |
| UnwrappedLineFormatter *BlockFormatter) |
| : LineFormatter(Indenter, Whitespaces, Style, BlockFormatter) {} |
| |
| /// Puts all tokens into a single line. |
| unsigned formatLine(const AnnotatedLine &Line, unsigned FirstIndent, |
| unsigned FirstStartColumn, bool DryRun) override { |
| unsigned Penalty = 0; |
| LineState State = |
| Indenter->getInitialState(FirstIndent, FirstStartColumn, &Line, DryRun); |
| while (State.NextToken) { |
| formatChildren(State, /*NewLine=*/false, DryRun, Penalty); |
| Indenter->addTokenToState( |
| State, /*Newline=*/State.NextToken->MustBreakBefore, DryRun); |
| } |
| return Penalty; |
| } |
| }; |
| |
| /// Finds the best way to break lines. |
| class OptimizingLineFormatter : public LineFormatter { |
| public: |
| OptimizingLineFormatter(ContinuationIndenter *Indenter, |
| WhitespaceManager *Whitespaces, |
| const FormatStyle &Style, |
| UnwrappedLineFormatter *BlockFormatter) |
| : LineFormatter(Indenter, Whitespaces, Style, BlockFormatter) {} |
| |
| /// Formats the line by finding the best line breaks with line lengths |
| /// below the column limit. |
| unsigned formatLine(const AnnotatedLine &Line, unsigned FirstIndent, |
| unsigned FirstStartColumn, bool DryRun) override { |
| LineState State = |
| Indenter->getInitialState(FirstIndent, FirstStartColumn, &Line, DryRun); |
| |
| // If the ObjC method declaration does not fit on a line, we should format |
| // it with one arg per line. |
| if (State.Line->Type == LT_ObjCMethodDecl) |
| State.Stack.back().BreakBeforeParameter = true; |
| |
| // Find best solution in solution space. |
| return analyzeSolutionSpace(State, DryRun); |
| } |
| |
| private: |
| struct CompareLineStatePointers { |
| bool operator()(LineState *obj1, LineState *obj2) const { |
| return *obj1 < *obj2; |
| } |
| }; |
| |
| /// A pair of <penalty, count> that is used to prioritize the BFS on. |
| /// |
| /// In case of equal penalties, we want to prefer states that were inserted |
| /// first. During state generation we make sure that we insert states first |
| /// that break the line as late as possible. |
| typedef std::pair<unsigned, unsigned> OrderedPenalty; |
| |
| /// An edge in the solution space from \c Previous->State to \c State, |
| /// inserting a newline dependent on the \c NewLine. |
| struct StateNode { |
| StateNode(const LineState &State, bool NewLine, StateNode *Previous) |
| : State(State), NewLine(NewLine), Previous(Previous) {} |
| LineState State; |
| bool NewLine; |
| StateNode *Previous; |
| }; |
| |
| /// An item in the prioritized BFS search queue. The \c StateNode's |
| /// \c State has the given \c OrderedPenalty. |
| typedef std::pair<OrderedPenalty, StateNode *> QueueItem; |
| |
| /// The BFS queue type. |
| typedef std::priority_queue<QueueItem, SmallVector<QueueItem>, |
| std::greater<QueueItem>> |
| QueueType; |
| |
| /// Analyze the entire solution space starting from \p InitialState. |
| /// |
| /// This implements a variant of Dijkstra's algorithm on the graph that spans |
| /// the solution space (\c LineStates are the nodes). The algorithm tries to |
| /// find the shortest path (the one with lowest penalty) from \p InitialState |
| /// to a state where all tokens are placed. Returns the penalty. |
| /// |
| /// If \p DryRun is \c false, directly applies the changes. |
| unsigned analyzeSolutionSpace(LineState &InitialState, bool DryRun) { |
| std::set<LineState *, CompareLineStatePointers> Seen; |
| |
| // Increasing count of \c StateNode items we have created. This is used to |
| // create a deterministic order independent of the container. |
| unsigned Count = 0; |
| QueueType Queue; |
| |
| // Insert start element into queue. |
| StateNode *RootNode = |
| new (Allocator.Allocate()) StateNode(InitialState, false, nullptr); |
| Queue.push(QueueItem(OrderedPenalty(0, Count), RootNode)); |
| ++Count; |
| |
| unsigned Penalty = 0; |
| |
| // While not empty, take first element and follow edges. |
| while (!Queue.empty()) { |
| // Quit if we still haven't found a solution by now. |
| if (Count > 25000000) |
| return 0; |
| |
| Penalty = Queue.top().first.first; |
| StateNode *Node = Queue.top().second; |
| if (!Node->State.NextToken) { |
| LLVM_DEBUG(llvm::dbgs() |
| << "\n---\nPenalty for line: " << Penalty << "\n"); |
| break; |
| } |
| Queue.pop(); |
| |
| // Cut off the analysis of certain solutions if the analysis gets too |
| // complex. See description of IgnoreStackForComparison. |
| if (Count > 50000) |
| Node->State.IgnoreStackForComparison = true; |
| |
| if (!Seen.insert(&Node->State).second) { |
| // State already examined with lower penalty. |
| continue; |
| } |
| |
| FormatDecision LastFormat = Node->State.NextToken->getDecision(); |
| if (LastFormat == FD_Unformatted || LastFormat == FD_Continue) |
| addNextStateToQueue(Penalty, Node, /*NewLine=*/false, &Count, &Queue); |
| if (LastFormat == FD_Unformatted || LastFormat == FD_Break) |
| addNextStateToQueue(Penalty, Node, /*NewLine=*/true, &Count, &Queue); |
| } |
| |
| if (Queue.empty()) { |
| // We were unable to find a solution, do nothing. |
| // FIXME: Add diagnostic? |
| LLVM_DEBUG(llvm::dbgs() << "Could not find a solution.\n"); |
| return 0; |
| } |
| |
| // Reconstruct the solution. |
| if (!DryRun) |
| reconstructPath(InitialState, Queue.top().second); |
| |
| LLVM_DEBUG(llvm::dbgs() |
| << "Total number of analyzed states: " << Count << "\n"); |
| LLVM_DEBUG(llvm::dbgs() << "---\n"); |
| |
| return Penalty; |
| } |
| |
| /// Add the following state to the analysis queue \c Queue. |
| /// |
| /// Assume the current state is \p PreviousNode and has been reached with a |
| /// penalty of \p Penalty. Insert a line break if \p NewLine is \c true. |
| void addNextStateToQueue(unsigned Penalty, StateNode *PreviousNode, |
| bool NewLine, unsigned *Count, QueueType *Queue) { |
| if (NewLine && !Indenter->canBreak(PreviousNode->State)) |
| return; |
| if (!NewLine && Indenter->mustBreak(PreviousNode->State)) |
| return; |
| |
| StateNode *Node = new (Allocator.Allocate()) |
| StateNode(PreviousNode->State, NewLine, PreviousNode); |
| if (!formatChildren(Node->State, NewLine, /*DryRun=*/true, Penalty)) |
| return; |
| |
| Penalty += Indenter->addTokenToState(Node->State, NewLine, true); |
| |
| Queue->push(QueueItem(OrderedPenalty(Penalty, *Count), Node)); |
| ++(*Count); |
| } |
| |
| /// Applies the best formatting by reconstructing the path in the |
| /// solution space that leads to \c Best. |
| void reconstructPath(LineState &State, StateNode *Best) { |
| llvm::SmallVector<StateNode *> Path; |
| // We do not need a break before the initial token. |
| while (Best->Previous) { |
| Path.push_back(Best); |
| Best = Best->Previous; |
| } |
| for (const auto &Node : llvm::reverse(Path)) { |
| unsigned Penalty = 0; |
| formatChildren(State, Node->NewLine, /*DryRun=*/false, Penalty); |
| Penalty += Indenter->addTokenToState(State, Node->NewLine, false); |
| |
| LLVM_DEBUG({ |
| printLineState(Node->Previous->State); |
| if (Node->NewLine) { |
| llvm::dbgs() << "Penalty for placing " |
| << Node->Previous->State.NextToken->Tok.getName() |
| << " on a new line: " << Penalty << "\n"; |
| } |
| }); |
| } |
| } |
| |
| llvm::SpecificBumpPtrAllocator<StateNode> Allocator; |
| }; |
| |
| } // anonymous namespace |
| |
| unsigned UnwrappedLineFormatter::format( |
| const SmallVectorImpl<AnnotatedLine *> &Lines, bool DryRun, |
| int AdditionalIndent, bool FixBadIndentation, unsigned FirstStartColumn, |
| unsigned NextStartColumn, unsigned LastStartColumn) { |
| LineJoiner Joiner(Style, Keywords, Lines); |
| |
| // Try to look up already computed penalty in DryRun-mode. |
| std::pair<const SmallVectorImpl<AnnotatedLine *> *, unsigned> CacheKey( |
| &Lines, AdditionalIndent); |
| auto CacheIt = PenaltyCache.find(CacheKey); |
| if (DryRun && CacheIt != PenaltyCache.end()) |
| return CacheIt->second; |
| |
| assert(!Lines.empty()); |
| unsigned Penalty = 0; |
| LevelIndentTracker IndentTracker(Style, Keywords, Lines[0]->Level, |
| AdditionalIndent); |
| const AnnotatedLine *PrevPrevLine = nullptr; |
| const AnnotatedLine *PreviousLine = nullptr; |
| const AnnotatedLine *NextLine = nullptr; |
| |
| // The minimum level of consecutive lines that have been formatted. |
| unsigned RangeMinLevel = UINT_MAX; |
| |
| bool FirstLine = true; |
| for (const AnnotatedLine *Line = |
| Joiner.getNextMergedLine(DryRun, IndentTracker); |
| Line; PrevPrevLine = PreviousLine, PreviousLine = Line, Line = NextLine, |
| FirstLine = false) { |
| assert(Line->First); |
| const AnnotatedLine &TheLine = *Line; |
| unsigned Indent = IndentTracker.getIndent(); |
| |
| // We continue formatting unchanged lines to adjust their indent, e.g. if a |
| // scope was added. However, we need to carefully stop doing this when we |
| // exit the scope of affected lines to prevent indenting the entire |
| // remaining file if it currently missing a closing brace. |
| bool PreviousRBrace = |
| PreviousLine && PreviousLine->startsWith(tok::r_brace); |
| bool ContinueFormatting = |
| TheLine.Level > RangeMinLevel || |
| (TheLine.Level == RangeMinLevel && !PreviousRBrace && |
| !TheLine.startsWith(tok::r_brace)); |
| |
| bool FixIndentation = (FixBadIndentation || ContinueFormatting) && |
| Indent != TheLine.First->OriginalColumn; |
| bool ShouldFormat = TheLine.Affected || FixIndentation; |
| // We cannot format this line; if the reason is that the line had a |
| // parsing error, remember that. |
| if (ShouldFormat && TheLine.Type == LT_Invalid && Status) { |
| Status->FormatComplete = false; |
| Status->Line = |
| SourceMgr.getSpellingLineNumber(TheLine.First->Tok.getLocation()); |
| } |
| |
| if (ShouldFormat && TheLine.Type != LT_Invalid) { |
| if (!DryRun) { |
| bool LastLine = TheLine.First->is(tok::eof); |
| formatFirstToken(TheLine, PreviousLine, PrevPrevLine, Lines, Indent, |
| LastLine ? LastStartColumn : NextStartColumn + Indent); |
| } |
| |
| NextLine = Joiner.getNextMergedLine(DryRun, IndentTracker); |
| unsigned ColumnLimit = getColumnLimit(TheLine.InPPDirective, NextLine); |
| bool FitsIntoOneLine = |
| !TheLine.ContainsMacroCall && |
| (TheLine.Last->TotalLength + Indent <= ColumnLimit || |
| (TheLine.Type == LT_ImportStatement && |
| (!Style.isJavaScript() || !Style.JavaScriptWrapImports)) || |
| (Style.isCSharp() && |
| TheLine.InPPDirective)); // don't split #regions in C# |
| if (Style.ColumnLimit == 0) { |
| NoColumnLimitLineFormatter(Indenter, Whitespaces, Style, this) |
| .formatLine(TheLine, NextStartColumn + Indent, |
| FirstLine ? FirstStartColumn : 0, DryRun); |
| } else if (FitsIntoOneLine) { |
| Penalty += NoLineBreakFormatter(Indenter, Whitespaces, Style, this) |
| .formatLine(TheLine, NextStartColumn + Indent, |
| FirstLine ? FirstStartColumn : 0, DryRun); |
| } else { |
| Penalty += OptimizingLineFormatter(Indenter, Whitespaces, Style, this) |
| .formatLine(TheLine, NextStartColumn + Indent, |
| FirstLine ? FirstStartColumn : 0, DryRun); |
| } |
| RangeMinLevel = std::min(RangeMinLevel, TheLine.Level); |
| } else { |
| // If no token in the current line is affected, we still need to format |
| // affected children. |
| if (TheLine.ChildrenAffected) { |
| for (const FormatToken *Tok = TheLine.First; Tok; Tok = Tok->Next) |
| if (!Tok->Children.empty()) |
| format(Tok->Children, DryRun); |
| } |
| |
| // Adapt following lines on the current indent level to the same level |
| // unless the current \c AnnotatedLine is not at the beginning of a line. |
| bool StartsNewLine = |
| TheLine.First->NewlinesBefore > 0 || TheLine.First->IsFirst; |
| if (StartsNewLine) |
| IndentTracker.adjustToUnmodifiedLine(TheLine); |
| if (!DryRun) { |
| bool ReformatLeadingWhitespace = |
| StartsNewLine && ((PreviousLine && PreviousLine->Affected) || |
| TheLine.LeadingEmptyLinesAffected); |
| // Format the first token. |
| if (ReformatLeadingWhitespace) { |
| formatFirstToken(TheLine, PreviousLine, PrevPrevLine, Lines, |
| TheLine.First->OriginalColumn, |
| TheLine.First->OriginalColumn); |
| } else { |
| Whitespaces->addUntouchableToken(*TheLine.First, |
| TheLine.InPPDirective); |
| } |
| |
| // Notify the WhitespaceManager about the unchanged whitespace. |
| for (FormatToken *Tok = TheLine.First->Next; Tok; Tok = Tok->Next) |
| Whitespaces->addUntouchableToken(*Tok, TheLine.InPPDirective); |
| } |
| NextLine = Joiner.getNextMergedLine(DryRun, IndentTracker); |
| RangeMinLevel = UINT_MAX; |
| } |
| if (!DryRun) |
| markFinalized(TheLine.First); |
| } |
| PenaltyCache[CacheKey] = Penalty; |
| return Penalty; |
| } |
| |
| static auto computeNewlines(const AnnotatedLine &Line, |
| const AnnotatedLine *PreviousLine, |
| const AnnotatedLine *PrevPrevLine, |
| const SmallVectorImpl<AnnotatedLine *> &Lines, |
| const FormatStyle &Style) { |
| const auto &RootToken = *Line.First; |
| auto Newlines = |
| std::min(RootToken.NewlinesBefore, Style.MaxEmptyLinesToKeep + 1); |
| // Remove empty lines before "}" where applicable. |
| if (RootToken.is(tok::r_brace) && |
| (!RootToken.Next || |
| (RootToken.Next->is(tok::semi) && !RootToken.Next->Next)) && |
| // Do not remove empty lines before namespace closing "}". |
| !getNamespaceToken(&Line, Lines)) { |
| Newlines = std::min(Newlines, 1u); |
| } |
| // Remove empty lines at the start of nested blocks (lambdas/arrow functions) |
| if (!PreviousLine && Line.Level > 0) |
| Newlines = std::min(Newlines, 1u); |
| if (Newlines == 0 && !RootToken.IsFirst) |
| Newlines = 1; |
| if (RootToken.IsFirst && !RootToken.HasUnescapedNewline) |
| Newlines = 0; |
| |
| // Remove empty lines after "{". |
| if (!Style.KeepEmptyLinesAtTheStartOfBlocks && PreviousLine && |
| PreviousLine->Last->is(tok::l_brace) && |
| !PreviousLine->startsWithNamespace() && |
| !(PrevPrevLine && PrevPrevLine->startsWithNamespace() && |
| PreviousLine->startsWith(tok::l_brace)) && |
| !startsExternCBlock(*PreviousLine)) { |
| Newlines = 1; |
| } |
| |
| // Insert or remove empty line before access specifiers. |
| if (PreviousLine && RootToken.isAccessSpecifier()) { |
| switch (Style.EmptyLineBeforeAccessModifier) { |
| case FormatStyle::ELBAMS_Never: |
| if (Newlines > 1) |
| Newlines = 1; |
| break; |
| case FormatStyle::ELBAMS_Leave: |
| Newlines = std::max(RootToken.NewlinesBefore, 1u); |
| break; |
| case FormatStyle::ELBAMS_LogicalBlock: |
| if (PreviousLine->Last->isOneOf(tok::semi, tok::r_brace) && Newlines <= 1) |
| Newlines = 2; |
| if (PreviousLine->First->isAccessSpecifier()) |
| Newlines = 1; // Previous is an access modifier remove all new lines. |
| break; |
| case FormatStyle::ELBAMS_Always: { |
| const FormatToken *previousToken; |
| if (PreviousLine->Last->is(tok::comment)) |
| previousToken = PreviousLine->Last->getPreviousNonComment(); |
| else |
| previousToken = PreviousLine->Last; |
| if ((!previousToken || previousToken->isNot(tok::l_brace)) && |
| Newlines <= 1) { |
| Newlines = 2; |
| } |
| } break; |
| } |
| } |
| |
| // Insert or remove empty line after access specifiers. |
| if (PreviousLine && PreviousLine->First->isAccessSpecifier() && |
| (!PreviousLine->InPPDirective || !RootToken.HasUnescapedNewline)) { |
| // EmptyLineBeforeAccessModifier is handling the case when two access |
| // modifiers follow each other. |
| if (!RootToken.isAccessSpecifier()) { |
| switch (Style.EmptyLineAfterAccessModifier) { |
| case FormatStyle::ELAAMS_Never: |
| Newlines = 1; |
| break; |
| case FormatStyle::ELAAMS_Leave: |
| Newlines = std::max(Newlines, 1u); |
| break; |
| case FormatStyle::ELAAMS_Always: |
| if (RootToken.is(tok::r_brace)) // Do not add at end of class. |
| Newlines = 1u; |
| else |
| Newlines = std::max(Newlines, 2u); |
| break; |
| } |
| } |
| } |
| |
| return Newlines; |
| } |
| |
| void UnwrappedLineFormatter::formatFirstToken( |
| const AnnotatedLine &Line, const AnnotatedLine *PreviousLine, |
| const AnnotatedLine *PrevPrevLine, |
| const SmallVectorImpl<AnnotatedLine *> &Lines, unsigned Indent, |
| unsigned NewlineIndent) { |
| FormatToken &RootToken = *Line.First; |
| if (RootToken.is(tok::eof)) { |
| unsigned Newlines = |
| std::min(RootToken.NewlinesBefore, |
| Style.KeepEmptyLinesAtEOF ? Style.MaxEmptyLinesToKeep + 1 : 1); |
| unsigned TokenIndent = Newlines ? NewlineIndent : 0; |
| Whitespaces->replaceWhitespace(RootToken, Newlines, TokenIndent, |
| TokenIndent); |
| return; |
| } |
| |
| if (RootToken.Newlines < 0) { |
| RootToken.Newlines = |
| computeNewlines(Line, PreviousLine, PrevPrevLine, Lines, Style); |
| assert(RootToken.Newlines >= 0); |
| } |
| |
| if (RootToken.Newlines > 0) |
| Indent = NewlineIndent; |
| |
| // Preprocessor directives get indented before the hash only if specified. In |
| // Javascript import statements are indented like normal statements. |
| if (!Style.isJavaScript() && |
| Style.IndentPPDirectives != FormatStyle::PPDIS_BeforeHash && |
| (Line.Type == LT_PreprocessorDirective || |
| Line.Type == LT_ImportStatement)) { |
| Indent = 0; |
| } |
| |
| Whitespaces->replaceWhitespace(RootToken, RootToken.Newlines, Indent, Indent, |
| /*IsAligned=*/false, |
| Line.InPPDirective && |
| !RootToken.HasUnescapedNewline); |
| } |
| |
| unsigned |
| UnwrappedLineFormatter::getColumnLimit(bool InPPDirective, |
| const AnnotatedLine *NextLine) const { |
| // In preprocessor directives reserve two chars for trailing " \" if the |
| // next line continues the preprocessor directive. |
| bool ContinuesPPDirective = |
| InPPDirective && |
| // If there is no next line, this is likely a child line and the parent |
| // continues the preprocessor directive. |
| (!NextLine || |
| (NextLine->InPPDirective && |
| // If there is an unescaped newline between this line and the next, the |
| // next line starts a new preprocessor directive. |
| !NextLine->First->HasUnescapedNewline)); |
| return Style.ColumnLimit - (ContinuesPPDirective ? 2 : 0); |
| } |
| |
| } // namespace format |
| } // namespace clang |