clang-tools  6.0.0
NamespaceAliaser.cpp
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1 //===---------- NamespaceAliaser.cpp - clang-tidy -------------------------===//
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 #include "NamespaceAliaser.h"
11 
12 #include "ASTUtils.h"
13 #include "clang/ASTMatchers/ASTMatchFinder.h"
14 #include "clang/ASTMatchers/ASTMatchers.h"
15 #include "clang/Lex/Lexer.h"
16 namespace clang {
17 namespace tidy {
18 namespace utils {
19 
20 using namespace ast_matchers;
21 
22 NamespaceAliaser::NamespaceAliaser(const SourceManager &SourceMgr)
23  : SourceMgr(SourceMgr) {}
24 
25 AST_MATCHER_P(NamespaceAliasDecl, hasTargetNamespace,
26  ast_matchers::internal::Matcher<NamespaceDecl>, innerMatcher) {
27  return innerMatcher.matches(*Node.getNamespace(), Finder, Builder);
28 }
29 
30 Optional<FixItHint>
31 NamespaceAliaser::createAlias(ASTContext &Context, const Stmt &Statement,
32  StringRef Namespace,
33  const std::vector<std::string> &Abbreviations) {
34  const FunctionDecl *Function = getSurroundingFunction(Context, Statement);
35  if (!Function || !Function->hasBody())
36  return None;
37 
38  if (AddedAliases[Function].count(Namespace.str()) != 0)
39  return None;
40 
41  // FIXME: Doesn't consider the order of declarations.
42  // If we accidentially pick an alias defined later in the function,
43  // the output won't compile.
44  // FIXME: Also doesn't consider file or class-scope aliases.
45 
46  const auto *ExistingAlias = selectFirst<NamedDecl>(
47  "alias",
48  match(functionDecl(hasBody(compoundStmt(has(declStmt(
49  has(namespaceAliasDecl(hasTargetNamespace(hasName(Namespace)))
50  .bind("alias"))))))),
51  *Function, Context));
52 
53  if (ExistingAlias != nullptr) {
54  AddedAliases[Function][Namespace.str()] = ExistingAlias->getName().str();
55  return None;
56  }
57 
58  for (const auto &Abbreviation : Abbreviations) {
59  DeclarationMatcher ConflictMatcher = namedDecl(hasName(Abbreviation));
60  const auto HasConflictingChildren =
61  !match(findAll(ConflictMatcher), *Function, Context).empty();
62  const auto HasConflictingAncestors =
63  !match(functionDecl(hasAncestor(decl(has(ConflictMatcher)))), *Function,
64  Context)
65  .empty();
66  if (HasConflictingAncestors || HasConflictingChildren)
67  continue;
68 
69  std::string Declaration =
70  (llvm::Twine("\nnamespace ") + Abbreviation + " = " + Namespace + ";")
71  .str();
72  SourceLocation Loc =
73  Lexer::getLocForEndOfToken(Function->getBody()->getLocStart(), 0,
74  SourceMgr, Context.getLangOpts());
75  AddedAliases[Function][Namespace.str()] = Abbreviation;
76  return FixItHint::CreateInsertion(Loc, Declaration);
77  }
78 
79  return None;
80 }
81 
82 std::string NamespaceAliaser::getNamespaceName(ASTContext &Context,
83  const Stmt &Statement,
84  StringRef Namespace) const {
85  const auto *Function = getSurroundingFunction(Context, Statement);
86  auto FunctionAliases = AddedAliases.find(Function);
87  if (FunctionAliases != AddedAliases.end()) {
88  if (FunctionAliases->second.count(Namespace) != 0) {
89  return FunctionAliases->second.find(Namespace)->getValue();
90  }
91  }
92  return Namespace.str();
93 }
94 
95 } // namespace utils
96 } // namespace tidy
97 } // namespace clang
SourceLocation Loc
&#39;#&#39; location in the include directive
NamespaceAliaser(const SourceManager &SourceMgr)
std::string getNamespaceName(ASTContext &Context, const Stmt &Statement, llvm::StringRef Namespace) const
const FunctionDecl * getSurroundingFunction(ASTContext &Context, const Stmt &Statement)
Definition: ASTUtils.cpp:21
llvm::Optional< FixItHint > createAlias(ASTContext &Context, const Stmt &Statement, llvm::StringRef Namespace, const std::vector< std::string > &Abbreviations)
AST_MATCHER_P(NamespaceAliasDecl, hasTargetNamespace, ast_matchers::internal::Matcher< NamespaceDecl >, innerMatcher)