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TokenAnnotator.h
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1 //===--- TokenAnnotator.h - Format C++ code ---------------------*- C++ -*-===//
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 a token annotator, i.e. creates
11 /// \c AnnotatedTokens out of \c FormatTokens with required extra information.
12 ///
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_CLANG_LIB_FORMAT_TOKENANNOTATOR_H
16 #define LLVM_CLANG_LIB_FORMAT_TOKENANNOTATOR_H
17 
18 #include "UnwrappedLineParser.h"
19 #include "clang/Format/Format.h"
20 
21 namespace clang {
22 class SourceManager;
23 
24 namespace format {
25 
26 enum LineType {
29  LT_ObjCDecl, // An @interface, @implementation, or @protocol line.
31  LT_ObjCProperty, // An @property line.
35 };
36 
38 public:
40  : First(Line.Tokens.front().Tok), Level(Line.Level),
48  assert(!Line.Tokens.empty());
49 
50  // Calculate Next and Previous for all tokens. Note that we must overwrite
51  // Next and Previous for every token, as previous formatting runs might have
52  // left them in a different state.
53  First->Previous = nullptr;
54  FormatToken *Current = First;
55  for (std::list<UnwrappedLineNode>::const_iterator I = ++Line.Tokens.begin(),
56  E = Line.Tokens.end();
57  I != E; ++I) {
58  const UnwrappedLineNode &Node = *I;
59  Current->Next = I->Tok;
60  I->Tok->Previous = Current;
61  Current = Current->Next;
62  Current->Children.clear();
63  for (const auto &Child : Node.Children) {
64  Children.push_back(new AnnotatedLine(Child));
65  Current->Children.push_back(Children.back());
66  }
67  }
68  Last = Current;
69  Last->Next = nullptr;
70  }
71 
73  for (unsigned i = 0, e = Children.size(); i != e; ++i) {
74  delete Children[i];
75  }
76  FormatToken *Current = First;
77  while (Current) {
78  Current->Children.clear();
79  Current->Role.reset();
80  Current = Current->Next;
81  }
82  }
83 
84  /// \c true if this line starts with the given tokens in order, ignoring
85  /// comments.
86  template <typename... Ts> bool startsWith(Ts... Tokens) const {
87  return First && First->startsSequence(Tokens...);
88  }
89 
90  /// \c true if this line ends with the given tokens in reversed order,
91  /// ignoring comments.
92  /// For example, given tokens [T1, T2, T3, ...], the function returns true if
93  /// this line is like "... T3 T2 T1".
94  template <typename... Ts> bool endsWith(Ts... Tokens) const {
95  return Last && Last->endsSequence(Tokens...);
96  }
97 
98  /// \c true if this line looks like a function definition instead of a
99  /// function declaration. Asserts MightBeFunctionDecl.
101  assert(MightBeFunctionDecl);
102  // FIXME: Line.Last points to other characters than tok::semi
103  // and tok::lbrace.
104  return !Last->isOneOf(tok::semi, tok::comment);
105  }
106 
107  /// \c true if this line starts a namespace definition.
108  bool startsWithNamespace() const {
109  return startsWith(tok::kw_namespace) ||
110  startsWith(tok::kw_inline, tok::kw_namespace) ||
111  startsWith(tok::kw_export, tok::kw_namespace);
112  }
113 
116 
118 
120  unsigned Level;
127 
128  /// \c True if this line should be formatted, i.e. intersects directly or
129  /// indirectly with one of the input ranges.
130  bool Affected;
131 
132  /// \c True if the leading empty lines of this line intersect with one of the
133  /// input ranges.
135 
136  /// \c True if one of this line's children intersects with an input range.
138 
140 
141 private:
142  // Disallow copying.
143  AnnotatedLine(const AnnotatedLine &) = delete;
144  void operator=(const AnnotatedLine &) = delete;
145 };
146 
147 /// Determines extra information about the tokens comprising an
148 /// \c UnwrappedLine.
150 public:
152  : Style(Style), Keywords(Keywords) {}
153 
154  /// Adapts the indent levels of comment lines to the indent of the
155  /// subsequent line.
156  // FIXME: Can/should this be done in the UnwrappedLineParser?
157  void setCommentLineLevels(SmallVectorImpl<AnnotatedLine *> &Lines);
158 
159  void annotate(AnnotatedLine &Line);
160  void calculateFormattingInformation(AnnotatedLine &Line);
161 
162 private:
163  /// Calculate the penalty for splitting before \c Tok.
164  unsigned splitPenalty(const AnnotatedLine &Line, const FormatToken &Tok,
165  bool InFunctionDecl);
166 
167  bool spaceRequiredBetween(const AnnotatedLine &Line, const FormatToken &Left,
168  const FormatToken &Right);
169 
170  bool spaceRequiredBefore(const AnnotatedLine &Line, const FormatToken &Right);
171 
172  bool mustBreakBefore(const AnnotatedLine &Line, const FormatToken &Right);
173 
174  bool canBreakBefore(const AnnotatedLine &Line, const FormatToken &Right);
175 
176  bool mustBreakForReturnType(const AnnotatedLine &Line) const;
177 
178  void printDebugInfo(const AnnotatedLine &Line);
179 
180  void calculateUnbreakableTailLengths(AnnotatedLine &Line);
181 
182  const FormatStyle &Style;
183 
184  const AdditionalKeywords &Keywords;
185 };
186 
187 } // end namespace format
188 } // end namespace clang
189 
190 #endif
bool endsSequence(A K1, Ts... Tokens) const
true if this token ends a sequence with the given tokens in order, following the Previous pointers...
Definition: FormatToken.h:343
SmallVector< UnwrappedLine, 0 > Children
bool endsWith(Ts... Tokens) const
true if this line ends with the given tokens in reversed order, ignoring comments.
Token Tok
The Token.
Definition: FormatToken.h:128
std::unique_ptr< TokenRole > Role
A token can have a special role that can carry extra information about the token&#39;s formatting...
Definition: FormatToken.h:204
static LLVM_ATTRIBUTE_UNUSED void printDebugInfo(const UnwrappedLine &Line, StringRef Prefix="")
bool LeadingEmptyLinesAffected
True if the leading empty lines of this line intersect with one of the input ranges.
FormatToken * Next
The next token in the unwrapped line.
Definition: FormatToken.h:293
FormatToken * Previous
The previous token in the unwrapped line.
Definition: FormatToken.h:290
const FormatToken & Tok
bool ChildrenAffected
True if one of this line&#39;s children intersects with an input range.
An unwrapped line is a sequence of Token, that we would like to put on a single line if there was no ...
bool mightBeFunctionDefinition() const
true if this line looks like a function definition instead of a function declaration.
bool isOneOf(A K1, B K2) const
Definition: FormatToken.h:316
Determines extra information about the tokens comprising an UnwrappedLine.
std::list< UnwrappedLineNode > Tokens
The Tokens comprising this UnwrappedLine.
const AnnotatedLine * Line
SmallVector< AnnotatedLine *, 0 > Children
A wrapper around a Token storing information about the whitespace characters preceding it...
Definition: FormatToken.h:124
TokenAnnotator(const FormatStyle &Style, const AdditionalKeywords &Keywords)
bool Affected
True if this line should be formatted, i.e.
#define false
Definition: stdbool.h:33
Various functions to configurably format source code.
Encapsulates keywords that are context sensitive or for languages not properly supported by Clang&#39;s l...
Definition: FormatToken.h:667
This file contains the declaration of the UnwrappedLineParser, which turns a stream of tokens into Un...
bool startsWith(Ts... Tokens) const
true if this line starts with the given tokens in order, ignoring comments.
The FormatStyle is used to configure the formatting to follow specific guidelines.
Definition: Format.h:49
ast_type_traits::DynTypedNode Node
Dataflow Directional Tag Classes.
AnnotatedLine(const UnwrappedLine &Line)
bool startsWithNamespace() const
true if this line starts a namespace definition.
SmallVector< AnnotatedLine *, 1 > Children
If this token starts a block, this contains all the unwrapped lines in it.
Definition: FormatToken.h:297
bool startsSequence(A K1, Ts... Tokens) const
true if this token starts a sequence with the given tokens in order, following the Next pointers...
Definition: FormatToken.h:336
const FormatStyle & Style