1 //===--- LexerUtils.h - clang-tidy-------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8
9 #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_UTILS_LEXER_UTILS_H
10 #define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_UTILS_LEXER_UTILS_H
11
12 #include "clang/AST/ASTContext.h"
13 #include "clang/Basic/TokenKinds.h"
14 #include "clang/Lex/Lexer.h"
15 #include <optional>
16 #include <utility>
17
18 namespace clang {
19
20 class Stmt;
21
22 namespace tidy::utils::lexer {
23
24 /// Returns previous token or ``tok::unknown`` if not found.
25 Token getPreviousToken(SourceLocation Location, const SourceManager &SM,
26 const LangOptions &LangOpts, bool SkipComments = true);
27 std::pair<Token, SourceLocation>
28 getPreviousTokenAndStart(SourceLocation Location, const SourceManager &SM,
29 const LangOptions &LangOpts, bool SkipComments = true);
30
31 SourceLocation findPreviousTokenStart(SourceLocation Start,
32 const SourceManager &SM,
33 const LangOptions &LangOpts);
34
35 SourceLocation findPreviousTokenKind(SourceLocation Start,
36 const SourceManager &SM,
37 const LangOptions &LangOpts,
38 tok::TokenKind TK);
39
40 SourceLocation findNextTerminator(SourceLocation Start, const SourceManager &SM,
41 const LangOptions &LangOpts);
42
43 template <typename TokenKind, typename... TokenKinds>
findPreviousAnyTokenKind(SourceLocation Start,const SourceManager & SM,const LangOptions & LangOpts,TokenKind TK,TokenKinds...TKs)44 SourceLocation findPreviousAnyTokenKind(SourceLocation Start,
45 const SourceManager &SM,
46 const LangOptions &LangOpts,
47 TokenKind TK, TokenKinds... TKs) {
48 if (Start.isInvalid() || Start.isMacroID())
49 return {};
50 while (true) {
51 SourceLocation L = findPreviousTokenStart(Start, SM, LangOpts);
52 if (L.isInvalid() || L.isMacroID())
53 return {};
54
55 Token T;
56 // Returning 'true' is used to signal failure to retrieve the token.
57 if (Lexer::getRawToken(L, T, SM, LangOpts, /*IgnoreWhiteSpace=*/true))
58 return {};
59
60 if (T.isOneOf(TK, TKs...))
61 return T.getLocation();
62
63 Start = L;
64 }
65 }
66
67 template <typename TokenKind, typename... TokenKinds>
findNextAnyTokenKind(SourceLocation Start,const SourceManager & SM,const LangOptions & LangOpts,TokenKind TK,TokenKinds...TKs)68 SourceLocation findNextAnyTokenKind(SourceLocation Start,
69 const SourceManager &SM,
70 const LangOptions &LangOpts, TokenKind TK,
71 TokenKinds... TKs) {
72 while (true) {
73 std::optional<Token> CurrentToken =
74 Lexer::findNextToken(Start, SM, LangOpts);
75
76 if (!CurrentToken)
77 return {};
78
79 Token PotentialMatch = *CurrentToken;
80 if (PotentialMatch.isOneOf(TK, TKs...))
81 return PotentialMatch.getLocation();
82
83 // If we reach the end of the file, and eof is not the target token, we stop
84 // the loop, otherwise we will get infinite loop (findNextToken will return
85 // eof on eof).
86 if (PotentialMatch.is(tok::eof))
87 return {};
88 Start = PotentialMatch.getLastLoc();
89 }
90 }
91
92 std::optional<Token>
93 findNextTokenIncludingComments(SourceLocation Start, const SourceManager &SM,
94 const LangOptions &LangOpts);
95
96 // Finds next token that's not a comment.
97 std::optional<Token> findNextTokenSkippingComments(SourceLocation Start,
98 const SourceManager &SM,
99 const LangOptions &LangOpts);
100
101 /// Re-lex the provide \p Range and return \c false if either a macro spans
102 /// multiple tokens, a pre-processor directive or failure to retrieve the
103 /// next token is found, otherwise \c true.
104 bool rangeContainsExpansionsOrDirectives(SourceRange Range,
105 const SourceManager &SM,
106 const LangOptions &LangOpts);
107
108 /// Assuming that ``Range`` spans a CVR-qualified type, returns the
109 /// token in ``Range`` that is responsible for the qualification. ``Range``
110 /// must be valid with respect to ``SM``. Returns ``std::nullopt`` if no
111 /// qualifying tokens are found.
112 /// \note: doesn't support member function qualifiers.
113 std::optional<Token> getQualifyingToken(tok::TokenKind TK,
114 CharSourceRange Range,
115 const ASTContext &Context,
116 const SourceManager &SM);
117
118 /// Stmt->getEndLoc does not always behave the same way depending on Token type.
119 /// See implementation for exceptions.
120 SourceLocation getUnifiedEndLoc(const Stmt &S, const SourceManager &SM,
121 const LangOptions &LangOpts);
122
123 /// For a given FunctionDecl returns the location where you would need to place
124 /// the noexcept specifier.
125 SourceLocation getLocationForNoexceptSpecifier(const FunctionDecl *FuncDecl,
126 const SourceManager &SM);
127
128 } // namespace tidy::utils::lexer
129 } // namespace clang
130
131 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_UTILS_LEXER_UTILS_H
132