clang  6.0.0svn
NamespaceEndCommentsFixer.cpp
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1 //===--- NamespaceEndCommentsFixer.cpp --------------------------*- 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 NamespaceEndCommentsFixer, a TokenAnalyzer that
12 /// fixes namespace end comments.
13 ///
14 //===----------------------------------------------------------------------===//
15 
17 #include "llvm/Support/Debug.h"
18 #include "llvm/Support/Regex.h"
19 
20 #define DEBUG_TYPE "namespace-end-comments-fixer"
21 
22 namespace clang {
23 namespace format {
24 
25 namespace {
26 // The maximal number of unwrapped lines that a short namespace spans.
27 // Short namespaces don't need an end comment.
28 static const int kShortNamespaceMaxLines = 1;
29 
30 // Matches a valid namespace end comment.
31 // Valid namespace end comments don't need to be edited.
32 static llvm::Regex kNamespaceCommentPattern =
33  llvm::Regex("^/[/*] *(end (of )?)? *(anonymous|unnamed)? *"
34  "namespace( +([a-zA-Z0-9:_]+))?\\.? *(\\*/)?$",
35  llvm::Regex::IgnoreCase);
36 
37 // Computes the name of a namespace given the namespace token.
38 // Returns "" for anonymous namespace.
39 std::string computeName(const FormatToken *NamespaceTok) {
40  assert(NamespaceTok && NamespaceTok->is(tok::kw_namespace) &&
41  "expecting a namespace token");
42  std::string name = "";
43  // Collects all the non-comment tokens between 'namespace' and '{'.
44  const FormatToken *Tok = NamespaceTok->getNextNonComment();
45  while (Tok && !Tok->is(tok::l_brace)) {
46  name += Tok->TokenText;
47  Tok = Tok->getNextNonComment();
48  }
49  return name;
50 }
51 
52 std::string computeEndCommentText(StringRef NamespaceName, bool AddNewline) {
53  std::string text = "// namespace";
54  if (!NamespaceName.empty()) {
55  text += ' ';
56  text += NamespaceName;
57  }
58  if (AddNewline)
59  text += '\n';
60  return text;
61 }
62 
63 bool hasEndComment(const FormatToken *RBraceTok) {
64  return RBraceTok->Next && RBraceTok->Next->is(tok::comment);
65 }
66 
67 bool validEndComment(const FormatToken *RBraceTok, StringRef NamespaceName) {
68  assert(hasEndComment(RBraceTok));
69  const FormatToken *Comment = RBraceTok->Next;
70  SmallVector<StringRef, 7> Groups;
71  if (kNamespaceCommentPattern.match(Comment->TokenText, &Groups)) {
72  StringRef NamespaceNameInComment = Groups.size() > 5 ? Groups[5] : "";
73  // Anonymous namespace comments must not mention a namespace name.
74  if (NamespaceName.empty() && !NamespaceNameInComment.empty())
75  return false;
76  StringRef AnonymousInComment = Groups.size() > 3 ? Groups[3] : "";
77  // Named namespace comments must not mention anonymous namespace.
78  if (!NamespaceName.empty() && !AnonymousInComment.empty())
79  return false;
80  return NamespaceNameInComment == NamespaceName;
81  }
82  return false;
83 }
84 
85 void addEndComment(const FormatToken *RBraceTok, StringRef EndCommentText,
86  const SourceManager &SourceMgr,
87  tooling::Replacements *Fixes) {
88  auto EndLoc = RBraceTok->Tok.getEndLoc();
89  auto Range = CharSourceRange::getCharRange(EndLoc, EndLoc);
90  auto Err = Fixes->add(tooling::Replacement(SourceMgr, Range, EndCommentText));
91  if (Err) {
92  llvm::errs() << "Error while adding namespace end comment: "
93  << llvm::toString(std::move(Err)) << "\n";
94  }
95 }
96 
97 void updateEndComment(const FormatToken *RBraceTok, StringRef EndCommentText,
98  const SourceManager &SourceMgr,
99  tooling::Replacements *Fixes) {
100  assert(hasEndComment(RBraceTok));
101  const FormatToken *Comment = RBraceTok->Next;
102  auto Range = CharSourceRange::getCharRange(Comment->getStartOfNonWhitespace(),
103  Comment->Tok.getEndLoc());
104  auto Err = Fixes->add(tooling::Replacement(SourceMgr, Range, EndCommentText));
105  if (Err) {
106  llvm::errs() << "Error while updating namespace end comment: "
107  << llvm::toString(std::move(Err)) << "\n";
108  }
109 }
110 
111 const FormatToken *
112 getNamespaceToken(const AnnotatedLine *line,
113  const SmallVectorImpl<AnnotatedLine *> &AnnotatedLines) {
114  if (!line->Affected || line->InPPDirective || !line->startsWith(tok::r_brace))
115  return nullptr;
116  size_t StartLineIndex = line->MatchingOpeningBlockLineIndex;
117  if (StartLineIndex == UnwrappedLine::kInvalidIndex)
118  return nullptr;
119  assert(StartLineIndex < AnnotatedLines.size());
120  const FormatToken *NamespaceTok = AnnotatedLines[StartLineIndex]->First;
121  if (NamespaceTok->is(tok::l_brace)) {
122  // "namespace" keyword can be on the line preceding '{', e.g. in styles
123  // where BraceWrapping.AfterNamespace is true.
124  if (StartLineIndex > 0)
125  NamespaceTok = AnnotatedLines[StartLineIndex - 1]->First;
126  }
127  // Detect "(inline)? namespace" in the beginning of a line.
128  if (NamespaceTok->is(tok::kw_inline))
129  NamespaceTok = NamespaceTok->getNextNonComment();
130  if (!NamespaceTok || NamespaceTok->isNot(tok::kw_namespace))
131  return nullptr;
132  return NamespaceTok;
133 }
134 } // namespace
135 
137  const FormatStyle &Style)
138  : TokenAnalyzer(Env, Style) {}
139 
140 std::pair<tooling::Replacements, unsigned> NamespaceEndCommentsFixer::analyze(
141  TokenAnnotator &Annotator, SmallVectorImpl<AnnotatedLine *> &AnnotatedLines,
142  FormatTokenLexer &Tokens) {
143  const SourceManager &SourceMgr = Env.getSourceManager();
144  AffectedRangeMgr.computeAffectedLines(AnnotatedLines.begin(),
145  AnnotatedLines.end());
146  tooling::Replacements Fixes;
147  std::string AllNamespaceNames = "";
148  size_t StartLineIndex = SIZE_MAX;
149  unsigned int CompactedNamespacesCount = 0;
150  for (size_t I = 0, E = AnnotatedLines.size(); I != E; ++I) {
151  const AnnotatedLine *EndLine = AnnotatedLines[I];
152  const FormatToken *NamespaceTok =
153  getNamespaceToken(EndLine, AnnotatedLines);
154  if (!NamespaceTok)
155  continue;
156  FormatToken *RBraceTok = EndLine->First;
157  if (RBraceTok->Finalized)
158  continue;
159  RBraceTok->Finalized = true;
160  const FormatToken *EndCommentPrevTok = RBraceTok;
161  // Namespaces often end with '};'. In that case, attach namespace end
162  // comments to the semicolon tokens.
163  if (RBraceTok->Next && RBraceTok->Next->is(tok::semi)) {
164  EndCommentPrevTok = RBraceTok->Next;
165  }
166  if (StartLineIndex == SIZE_MAX)
167  StartLineIndex = EndLine->MatchingOpeningBlockLineIndex;
168  std::string NamespaceName = computeName(NamespaceTok);
169  if (Style.CompactNamespaces) {
170  if ((I + 1 < E) &&
171  getNamespaceToken(AnnotatedLines[I + 1], AnnotatedLines) &&
172  StartLineIndex - CompactedNamespacesCount - 1 ==
173  AnnotatedLines[I + 1]->MatchingOpeningBlockLineIndex &&
174  !AnnotatedLines[I + 1]->First->Finalized) {
175  if (hasEndComment(EndCommentPrevTok)) {
176  // remove end comment, it will be merged in next one
177  updateEndComment(EndCommentPrevTok, std::string(), SourceMgr, &Fixes);
178  }
179  CompactedNamespacesCount++;
180  AllNamespaceNames = "::" + NamespaceName + AllNamespaceNames;
181  continue;
182  }
183  NamespaceName += AllNamespaceNames;
184  CompactedNamespacesCount = 0;
185  AllNamespaceNames = std::string();
186  }
187  // The next token in the token stream after the place where the end comment
188  // token must be. This is either the next token on the current line or the
189  // first token on the next line.
190  const FormatToken *EndCommentNextTok = EndCommentPrevTok->Next;
191  if (EndCommentNextTok && EndCommentNextTok->is(tok::comment))
192  EndCommentNextTok = EndCommentNextTok->Next;
193  if (!EndCommentNextTok && I + 1 < E)
194  EndCommentNextTok = AnnotatedLines[I + 1]->First;
195  bool AddNewline = EndCommentNextTok &&
196  EndCommentNextTok->NewlinesBefore == 0 &&
197  EndCommentNextTok->isNot(tok::eof);
198  const std::string EndCommentText =
199  computeEndCommentText(NamespaceName, AddNewline);
200  if (!hasEndComment(EndCommentPrevTok)) {
201  bool isShort = I - StartLineIndex <= kShortNamespaceMaxLines + 1;
202  if (!isShort)
203  addEndComment(EndCommentPrevTok, EndCommentText, SourceMgr, &Fixes);
204  } else if (!validEndComment(EndCommentPrevTok, NamespaceName)) {
205  updateEndComment(EndCommentPrevTok, EndCommentText, SourceMgr, &Fixes);
206  }
207  StartLineIndex = SIZE_MAX;
208  }
209  return {Fixes, 0};
210 }
211 
212 } // namespace format
213 } // namespace clang
if(T->getSizeExpr()) TRY_TO(TraverseStmt(T -> getSizeExpr()))
NamespaceEndCommentsFixer(const Environment &Env, const FormatStyle &Style)
bool computeAffectedLines(SmallVectorImpl< AnnotatedLine *>::iterator I, SmallVectorImpl< AnnotatedLine *>::iterator E)
const FormatToken * getNextNonComment() const
Returns the next token ignoring comments.
Definition: FormatToken.h:456
Maintains a set of replacements that are conflict-free.
Definition: Replacement.h:205
AffectedRangeManager AffectedRangeMgr
unsigned NewlinesBefore
The number of newlines immediately before the Token.
Definition: FormatToken.h:130
FormatToken * Next
The next token in the unwrapped line.
Definition: FormatToken.h:283
const Environment & Env
bool isNot(T Kind) const
Definition: FormatToken.h:313
const FormatToken & Tok
const SourceManager & getSourceManager() const
Definition: TokenAnalyzer.h:76
Determines extra information about the tokens comprising an UnwrappedLine.
static const size_t kInvalidIndex
A wrapper around a Token storing information about the whitespace characters preceding it...
Definition: FormatToken.h:120
bool CompactNamespaces
If true, consecutive namespace declarations will be on the same line.
Definition: Format.h:883
static CharSourceRange getCharRange(SourceRange R)
std::pair< tooling::Replacements, unsigned > analyze(TokenAnnotator &Annotator, SmallVectorImpl< AnnotatedLine *> &AnnotatedLines, FormatTokenLexer &Tokens) override
bool is(tok::TokenKind Kind) const
Definition: FormatToken.h:297
StringRef TokenText
The raw text of the token.
Definition: FormatToken.h:168
#define SIZE_MAX
Definition: stdint.h:664
The FormatStyle is used to configure the formatting to follow specific guidelines.
Definition: Format.h:46
Dataflow Directional Tag Classes.
bool Finalized
If true, this token has been fully formatted (indented and potentially re-formatted inside)...
Definition: FormatToken.h:295
std::string toString(const til::SExpr *E)
const Expr * Replacement
Definition: AttributeList.h:59
This file declares NamespaceEndCommentsFixer, a TokenAnalyzer that fixes namespace end comments...
This class handles loading and caching of source files into memory.
const FormatStyle & Style