1//===--- AffectedRangeManager.cpp - Format C++ code -----------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8///
9/// \file
10/// This file implements AffectRangeManager class.
11///
12//===----------------------------------------------------------------------===//
13
14#include "AffectedRangeManager.h"
15
16#include "FormatToken.h"
17#include "TokenAnnotator.h"
18
19namespace clang {
20namespace format {
21
22bool AffectedRangeManager::computeAffectedLines(
23 SmallVectorImpl<AnnotatedLine *> &Lines) {
24 ArrayRef<AnnotatedLine *>::iterator I = Lines.begin();
25 ArrayRef<AnnotatedLine *>::iterator E = Lines.end();
26 bool SomeLineAffected = false;
27 const AnnotatedLine *PreviousLine = nullptr;
28 while (I != E) {
29 AnnotatedLine *Line = *I;
30 assert(Line->First);
31 Line->LeadingEmptyLinesAffected = affectsLeadingEmptyLines(Tok: *Line->First);
32
33 // If a line is part of a preprocessor directive, it needs to be formatted
34 // if any token within the directive is affected.
35 if (Line->InPPDirective) {
36 FormatToken *Last = Line->Last;
37 const auto *PPEnd = I + 1;
38 while (PPEnd != E && !(*PPEnd)->First->HasUnescapedNewline) {
39 Last = (*PPEnd)->Last;
40 ++PPEnd;
41 }
42
43 if (affectsTokenRange(First: *Line->First, Last: *Last,
44 /*IncludeLeadingNewlines=*/false)) {
45 SomeLineAffected = true;
46 markAllAsAffected(I, E: PPEnd);
47 }
48 I = PPEnd;
49 continue;
50 }
51
52 if (nonPPLineAffected(Line, PreviousLine, Lines))
53 SomeLineAffected = true;
54
55 PreviousLine = Line;
56 ++I;
57 }
58 return SomeLineAffected;
59}
60
61bool AffectedRangeManager::affectsCharSourceRange(
62 const CharSourceRange &Range) {
63 for (const CharSourceRange &R : Ranges) {
64 if (!SourceMgr.isBeforeInTranslationUnit(LHS: Range.getEnd(), RHS: R.getBegin()) &&
65 !SourceMgr.isBeforeInTranslationUnit(LHS: R.getEnd(), RHS: Range.getBegin())) {
66 return true;
67 }
68 }
69 return false;
70}
71
72bool AffectedRangeManager::affectsTokenRange(const FormatToken &First,
73 const FormatToken &Last,
74 bool IncludeLeadingNewlines) {
75 SourceLocation Start = First.WhitespaceRange.getBegin();
76 if (!IncludeLeadingNewlines)
77 Start = Start.getLocWithOffset(Offset: First.LastNewlineOffset);
78 SourceLocation End = Last.getStartOfNonWhitespace();
79 End = End.getLocWithOffset(Offset: Last.TokenText.size());
80 CharSourceRange Range = CharSourceRange::getCharRange(B: Start, E: End);
81 return affectsCharSourceRange(Range);
82}
83
84bool AffectedRangeManager::affectsLeadingEmptyLines(const FormatToken &Tok) {
85 CharSourceRange EmptyLineRange = CharSourceRange::getCharRange(
86 B: Tok.WhitespaceRange.getBegin(),
87 E: Tok.WhitespaceRange.getBegin().getLocWithOffset(Offset: Tok.LastNewlineOffset));
88 return affectsCharSourceRange(Range: EmptyLineRange);
89}
90
91void AffectedRangeManager::markAllAsAffected(
92 ArrayRef<AnnotatedLine *>::iterator I,
93 ArrayRef<AnnotatedLine *>::iterator E) {
94 while (I != E) {
95 (*I)->Affected = true;
96 markAllAsAffected(I: (*I)->Children.begin(), E: (*I)->Children.end());
97 ++I;
98 }
99}
100
101bool AffectedRangeManager::nonPPLineAffected(
102 AnnotatedLine *Line, const AnnotatedLine *PreviousLine,
103 SmallVectorImpl<AnnotatedLine *> &Lines) {
104 bool SomeLineAffected = false;
105 Line->ChildrenAffected = computeAffectedLines(Lines&: Line->Children);
106 if (Line->ChildrenAffected)
107 SomeLineAffected = true;
108
109 // Stores whether one of the line's tokens is directly affected.
110 bool SomeTokenAffected = false;
111 // Stores whether we need to look at the leading newlines of the next token
112 // in order to determine whether it was affected.
113 bool IncludeLeadingNewlines = false;
114
115 // Stores whether the first child line of any of this line's tokens is
116 // affected.
117 bool SomeFirstChildAffected = false;
118
119 assert(Line->First);
120 for (FormatToken *Tok = Line->First; Tok; Tok = Tok->Next) {
121 // Determine whether 'Tok' was affected.
122 if (affectsTokenRange(First: *Tok, Last: *Tok, IncludeLeadingNewlines))
123 SomeTokenAffected = true;
124
125 // Determine whether the first child of 'Tok' was affected.
126 if (!Tok->Children.empty() && Tok->Children.front()->Affected)
127 SomeFirstChildAffected = true;
128
129 IncludeLeadingNewlines = Tok->Children.empty();
130 }
131
132 // Was this line moved, i.e. has it previously been on the same line as an
133 // affected line?
134 bool LineMoved = PreviousLine && PreviousLine->Affected &&
135 Line->First->NewlinesBefore == 0;
136
137 bool IsContinuedComment =
138 Line->First->is(Kind: tok::comment) && !Line->First->Next &&
139 Line->First->NewlinesBefore < 2 && PreviousLine &&
140 PreviousLine->Affected && PreviousLine->Last->is(Kind: tok::comment);
141
142 bool IsAffectedClosingBrace =
143 Line->First->is(Kind: tok::r_brace) &&
144 Line->MatchingOpeningBlockLineIndex != UnwrappedLine::kInvalidIndex &&
145 Lines[Line->MatchingOpeningBlockLineIndex]->Affected;
146
147 if (SomeTokenAffected || SomeFirstChildAffected || LineMoved ||
148 IsContinuedComment || IsAffectedClosingBrace) {
149 Line->Affected = true;
150 SomeLineAffected = true;
151 }
152 return SomeLineAffected;
153}
154
155} // namespace format
156} // namespace clang
157