clang  7.0.0svn
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 /// 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),
49  assert(!Line.Tokens.empty());
50 
51  // Calculate Next and Previous for all tokens. Note that we must overwrite
52  // Next and Previous for every token, as previous formatting runs might have
53  // left them in a different state.
54  First->Previous = nullptr;
55  FormatToken *Current = First;
56  for (std::list<UnwrappedLineNode>::const_iterator I = ++Line.Tokens.begin(),
57  E = Line.Tokens.end();
58  I != E; ++I) {
59  const UnwrappedLineNode &Node = *I;
60  Current->Next = I->Tok;
61  I->Tok->Previous = Current;
62  Current = Current->Next;
63  Current->Children.clear();
64  for (const auto &Child : Node.Children) {
65  Children.push_back(new AnnotatedLine(Child));
66  Current->Children.push_back(Children.back());
67  }
68  }
69  Last = Current;
70  Last->Next = nullptr;
71  }
72 
74  for (unsigned i = 0, e = Children.size(); i != e; ++i) {
75  delete Children[i];
76  }
77  FormatToken *Current = First;
78  while (Current) {
79  Current->Children.clear();
80  Current->Role.reset();
81  Current = Current->Next;
82  }
83  }
84 
85  /// \c true if this line starts with the given tokens in order, ignoring
86  /// comments.
87  template <typename... Ts> bool startsWith(Ts... Tokens) const {
88  return First && First->startsSequence(Tokens...);
89  }
90 
91  /// \c true if this line ends with the given tokens in reversed order,
92  /// ignoring comments.
93  /// For example, given tokens [T1, T2, T3, ...], the function returns true if
94  /// this line is like "... T3 T2 T1".
95  template <typename... Ts> bool endsWith(Ts... Tokens) const {
96  return Last && Last->endsSequence(Tokens...);
97  }
98 
99  /// \c true if this line looks like a function definition instead of a
100  /// function declaration. Asserts MightBeFunctionDecl.
102  assert(MightBeFunctionDecl);
103  // FIXME: Line.Last points to other characters than tok::semi
104  // and tok::lbrace.
105  return !Last->isOneOf(tok::semi, tok::comment);
106  }
107 
110 
112 
114  unsigned Level;
121 
122  /// \c True if this line should be formatted, i.e. intersects directly or
123  /// indirectly with one of the input ranges.
124  bool Affected;
125 
126  /// \c True if the leading empty lines of this line intersect with one of the
127  /// input ranges.
129 
130  /// \c True if one of this line's children intersects with an input range.
132 
134 
135 private:
136  // Disallow copying.
137  AnnotatedLine(const AnnotatedLine &) = delete;
138  void operator=(const AnnotatedLine &) = delete;
139 };
140 
141 /// Determines extra information about the tokens comprising an
142 /// \c UnwrappedLine.
144 public:
146  : Style(Style), Keywords(Keywords) {}
147 
148  /// Adapts the indent levels of comment lines to the indent of the
149  /// subsequent line.
150  // FIXME: Can/should this be done in the UnwrappedLineParser?
151  void setCommentLineLevels(SmallVectorImpl<AnnotatedLine *> &Lines);
152 
153  void annotate(AnnotatedLine &Line);
154  void calculateFormattingInformation(AnnotatedLine &Line);
155 
156 private:
157  /// Calculate the penalty for splitting before \c Tok.
158  unsigned splitPenalty(const AnnotatedLine &Line, const FormatToken &Tok,
159  bool InFunctionDecl);
160 
161  bool spaceRequiredBetween(const AnnotatedLine &Line, const FormatToken &Left,
162  const FormatToken &Right);
163 
164  bool spaceRequiredBefore(const AnnotatedLine &Line, const FormatToken &Right);
165 
166  bool mustBreakBefore(const AnnotatedLine &Line, const FormatToken &Right);
167 
168  bool canBreakBefore(const AnnotatedLine &Line, const FormatToken &Right);
169 
170  bool mustBreakForReturnType(const AnnotatedLine &Line) const;
171 
172  void printDebugInfo(const AnnotatedLine &Line);
173 
174  void calculateUnbreakableTailLengths(AnnotatedLine &Line);
175 
176  const FormatStyle &Style;
177 
178  const AdditionalKeywords &Keywords;
179 };
180 
181 } // end namespace format
182 } // end namespace clang
183 
184 #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:338
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:207
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:296
FormatToken * Previous
The previous token in the unwrapped line.
Definition: FormatToken.h:293
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:319
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:123
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:655
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:48
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:300
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:331
const FormatStyle & Style