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TokenAnnotator.h
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1 //===--- TokenAnnotator.h - Format C++ code ---------------------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 ///
10 /// \file
11 /// \brief This file implements a token annotator, i.e. creates
12 /// \c AnnotatedTokens out of \c FormatTokens with required extra information.
13 ///
14 //===----------------------------------------------------------------------===//
15 
16 #ifndef LLVM_CLANG_LIB_FORMAT_TOKENANNOTATOR_H
17 #define LLVM_CLANG_LIB_FORMAT_TOKENANNOTATOR_H
18 
19 #include "UnwrappedLineParser.h"
20 #include "clang/Format/Format.h"
21 
22 namespace clang {
23 class SourceManager;
24 
25 namespace format {
26 
27 enum LineType {
30  LT_ObjCDecl, // An @interface, @implementation, or @protocol line.
32  LT_ObjCProperty, // An @property line.
36 };
37 
39 public:
41  : 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 
109 
111 
113  unsigned Level;
119 
120  /// \c True if this line should be formatted, i.e. intersects directly or
121  /// indirectly with one of the input ranges.
122  bool Affected;
123 
124  /// \c True if the leading empty lines of this line intersect with one of the
125  /// input ranges.
127 
128  /// \c True if one of this line's children intersects with an input range.
130 
132 
133 private:
134  // Disallow copying.
135  AnnotatedLine(const AnnotatedLine &) = delete;
136  void operator=(const AnnotatedLine &) = delete;
137 };
138 
139 /// \brief Determines extra information about the tokens comprising an
140 /// \c UnwrappedLine.
142 public:
144  : Style(Style), Keywords(Keywords) {}
145 
146  /// \brief Adapts the indent levels of comment lines to the indent of the
147  /// subsequent line.
148  // FIXME: Can/should this be done in the UnwrappedLineParser?
149  void setCommentLineLevels(SmallVectorImpl<AnnotatedLine *> &Lines);
150 
151  void annotate(AnnotatedLine &Line);
152  void calculateFormattingInformation(AnnotatedLine &Line);
153 
154 private:
155  /// \brief Calculate the penalty for splitting before \c Tok.
156  unsigned splitPenalty(const AnnotatedLine &Line, const FormatToken &Tok,
157  bool InFunctionDecl);
158 
159  bool spaceRequiredBetween(const AnnotatedLine &Line, const FormatToken &Left,
160  const FormatToken &Right);
161 
162  bool spaceRequiredBefore(const AnnotatedLine &Line, const FormatToken &Tok);
163 
164  bool mustBreakBefore(const AnnotatedLine &Line, const FormatToken &Right);
165 
166  bool canBreakBefore(const AnnotatedLine &Line, const FormatToken &Right);
167 
168  bool mustBreakForReturnType(const AnnotatedLine &Line) const;
169 
170  void printDebugInfo(const AnnotatedLine &Line);
171 
172  void calculateUnbreakableTailLengths(AnnotatedLine &Line);
173 
174  const FormatStyle &Style;
175 
176  const AdditionalKeywords &Keywords;
177 };
178 
179 } // end namespace format
180 } // end namespace clang
181 
182 #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:325
SmallVector< UnwrappedLine, 0 > Children
bool endsWith(Ts... Tokens) const
true if this line ends with the given tokens in reversed order, ignoring comments.
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:283
FormatToken * Previous
The previous token in the unwrapped line.
Definition: FormatToken.h:280
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:306
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:120
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:634
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:46
ast_type_traits::DynTypedNode Node
Dataflow Directional Tag Classes.
AnnotatedLine(const UnwrappedLine &Line)
SmallVector< AnnotatedLine *, 1 > Children
If this token starts a block, this contains all the unwrapped lines in it.
Definition: FormatToken.h:287
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:318
const FormatStyle & Style