clang-tools  8.0.0
MagicNumbersCheck.h
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1 //===--- MagicNumbersCheck.h - clang-tidy-----------------------*- 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 #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_MAGICNUMBERSCHECK_H
11 #define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_MAGICNUMBERSCHECK_H
12 
13 #include "../ClangTidy.h"
14 #include <llvm/ADT/APFloat.h>
15 #include <llvm/ADT/SmallVector.h>
16 #include <vector>
17 
18 namespace clang {
19 namespace tidy {
20 namespace readability {
21 
22 /// Detects magic numbers, integer and floating point literals embedded in code.
23 ///
24 /// For the user-facing documentation see:
25 /// http://clang.llvm.org/extra/clang-tidy/checks/readability-magic-numbers.html
27 public:
28  MagicNumbersCheck(StringRef Name, ClangTidyContext *Context);
29  void storeOptions(ClangTidyOptions::OptionMap &Opts) override;
30  void registerMatchers(ast_matchers::MatchFinder *Finder) override;
31  void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
32 
33 private:
34  bool isConstant(const clang::ast_matchers::MatchFinder::MatchResult &Result,
35  const clang::Expr &ExprResult) const;
36 
37  bool isIgnoredValue(const IntegerLiteral *Literal) const;
38  bool isIgnoredValue(const FloatingLiteral *Literal) const;
39 
40  bool isSyntheticValue(const clang::SourceManager *,
41  const FloatingLiteral *) const {
42  return false;
43  }
44 
45  bool isSyntheticValue(const clang::SourceManager *SourceManager,
46  const IntegerLiteral *Literal) const;
47 
48  template <typename L>
49  void checkBoundMatch(const ast_matchers::MatchFinder::MatchResult &Result,
50  const char *BoundName) {
51  const L *MatchedLiteral = Result.Nodes.getNodeAs<L>(BoundName);
52  if (!MatchedLiteral)
53  return;
54 
55  if (Result.SourceManager->isMacroBodyExpansion(
56  MatchedLiteral->getLocation()))
57  return;
58 
59  if (isIgnoredValue(MatchedLiteral))
60  return;
61 
62  if (isConstant(Result, *MatchedLiteral))
63  return;
64 
65  if (isSyntheticValue(Result.SourceManager, MatchedLiteral))
66  return;
67 
68  const StringRef LiteralSourceText = Lexer::getSourceText(
69  CharSourceRange::getTokenRange(MatchedLiteral->getSourceRange()),
70  *Result.SourceManager, getLangOpts());
71 
72  diag(MatchedLiteral->getLocation(),
73  "%0 is a magic number; consider replacing it with a named constant")
74  << LiteralSourceText;
75  }
76 
77  const bool IgnoreAllFloatingPointValues;
78  const bool IgnorePowersOf2IntegerValues;
79 
80  constexpr static unsigned SensibleNumberOfMagicValueExceptions = 16;
81 
82  constexpr static llvm::APFloat::roundingMode DefaultRoundingMode =
83  llvm::APFloat::rmNearestTiesToEven;
84 
85  llvm::SmallVector<int64_t, SensibleNumberOfMagicValueExceptions>
86  IgnoredIntegerValues;
87  llvm::SmallVector<float, SensibleNumberOfMagicValueExceptions>
88  IgnoredFloatingPointValues;
89  llvm::SmallVector<double, SensibleNumberOfMagicValueExceptions>
90  IgnoredDoublePointValues;
91 };
92 
93 } // namespace readability
94 } // namespace tidy
95 } // namespace clang
96 
97 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_READABILITY_MAGICNUMBERSCHECK_H
void check(const ast_matchers::MatchFinder::MatchResult &Result) override
ClangTidyChecks that register ASTMatchers should do the actual work in here.
LangOptions getLangOpts() const
Returns the language options from the context.
Definition: ClangTidy.h:187
Base class for all clang-tidy checks.
Definition: ClangTidy.h:127
void registerMatchers(ast_matchers::MatchFinder *Finder) override
Override this to register AST matchers with Finder.
Detects magic numbers, integer and floating point literals embedded in code.
static constexpr llvm::StringLiteral Name
std::map< std::string, std::string > OptionMap
llvm::Optional< llvm::Expected< tooling::AtomicChanges > > Result
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
Every ClangTidyCheck reports errors through a DiagnosticsEngine provided by this context.
MagicNumbersCheck(StringRef Name, ClangTidyContext *Context)
DiagnosticBuilder diag(SourceLocation Loc, StringRef Description, DiagnosticIDs::Level Level=DiagnosticIDs::Warning)
Add a diagnostic with the check&#39;s name.
Definition: ClangTidy.cpp:438
void storeOptions(ClangTidyOptions::OptionMap &Opts) override
Should store all options supported by this check with their current values or default values for opti...