1 //===--- FormatTokenLexer.h - Format C++ code ----------------*- 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 /// \file 10 /// This file contains FormatTokenLexer, which tokenizes a source file 11 /// into a token stream suitable for ClangFormat. 12 /// 13 //===----------------------------------------------------------------------===// 14 15 #ifndef LLVM_CLANG_LIB_FORMAT_FORMATTOKENLEXER_H 16 #define LLVM_CLANG_LIB_FORMAT_FORMATTOKENLEXER_H 17 18 #include "Encoding.h" 19 #include "FormatToken.h" 20 #include "clang/Basic/LangOptions.h" 21 #include "clang/Basic/SourceLocation.h" 22 #include "clang/Basic/SourceManager.h" 23 #include "clang/Format/Format.h" 24 #include "llvm/ADT/MapVector.h" 25 #include "llvm/ADT/SmallPtrSet.h" 26 #include "llvm/ADT/StringSet.h" 27 #include "llvm/Support/Regex.h" 28 29 #include <stack> 30 31 namespace clang { 32 namespace format { 33 34 enum LexerState { 35 NORMAL, 36 TEMPLATE_STRING, 37 TOKEN_STASHED, 38 }; 39 40 class FormatTokenLexer { 41 public: 42 FormatTokenLexer(const SourceManager &SourceMgr, FileID ID, unsigned Column, 43 const FormatStyle &Style, encoding::Encoding Encoding, 44 llvm::SpecificBumpPtrAllocator<FormatToken> &Allocator, 45 IdentifierTable &IdentTable); 46 47 ArrayRef<FormatToken *> lex(); 48 49 const AdditionalKeywords &getKeywords() { return Keywords; } 50 51 private: 52 void tryMergePreviousTokens(); 53 54 bool tryMergeLessLess(); 55 bool tryMergeGreaterGreater(); 56 bool tryMergeNSStringLiteral(); 57 bool tryMergeJSPrivateIdentifier(); 58 bool tryMergeCSharpStringLiteral(); 59 bool tryMergeCSharpKeywordVariables(); 60 bool tryMergeNullishCoalescingEqual(); 61 bool tryTransformCSharpForEach(); 62 bool tryMergeForEach(); 63 bool tryTransformTryUsageForC(); 64 65 // Merge the most recently lexed tokens into a single token if their kinds are 66 // correct. 67 bool tryMergeTokens(ArrayRef<tok::TokenKind> Kinds, TokenType NewType); 68 // Merge without checking their kinds. 69 bool tryMergeTokens(size_t Count, TokenType NewType); 70 // Merge if their kinds match any one of Kinds. 71 bool tryMergeTokensAny(ArrayRef<ArrayRef<tok::TokenKind>> Kinds, 72 TokenType NewType); 73 74 // Returns \c true if \p Tok can only be followed by an operand in JavaScript. 75 bool precedesOperand(FormatToken *Tok); 76 77 bool canPrecedeRegexLiteral(FormatToken *Prev); 78 79 // Tries to parse a JavaScript Regex literal starting at the current token, 80 // if that begins with a slash and is in a location where JavaScript allows 81 // regex literals. Changes the current token to a regex literal and updates 82 // its text if successful. 83 void tryParseJSRegexLiteral(); 84 85 // Handles JavaScript template strings. 86 // 87 // JavaScript template strings use backticks ('`') as delimiters, and allow 88 // embedding expressions nested in ${expr-here}. Template strings can be 89 // nested recursively, i.e. expressions can contain template strings in turn. 90 // 91 // The code below parses starting from a backtick, up to a closing backtick or 92 // an opening ${. It also maintains a stack of lexing contexts to handle 93 // nested template parts by balancing curly braces. 94 void handleTemplateStrings(); 95 96 void handleCSharpVerbatimAndInterpolatedStrings(); 97 98 // Handles TableGen multiline strings. It has the form [{ ... }]. 99 void handleTableGenMultilineString(); 100 // Handles TableGen numeric like identifiers. 101 // They have a forms of [0-9]*[_a-zA-Z]([_a-zA-Z0-9]*). But limited to the 102 // case it is not lexed as an integer. 103 void handleTableGenNumericLikeIdentifier(); 104 105 void tryParsePythonComment(); 106 107 bool tryMerge_TMacro(); 108 109 bool tryMergeConflictMarkers(); 110 111 void truncateToken(size_t NewLen); 112 113 FormatToken *getStashedToken(); 114 115 FormatToken *getNextToken(); 116 117 FormatToken *FormatTok; 118 bool IsFirstToken; 119 std::stack<LexerState> StateStack; 120 unsigned Column; 121 unsigned TrailingWhitespace; 122 std::unique_ptr<Lexer> Lex; 123 LangOptions LangOpts; 124 const SourceManager &SourceMgr; 125 FileID ID; 126 const FormatStyle &Style; 127 IdentifierTable &IdentTable; 128 AdditionalKeywords Keywords; 129 encoding::Encoding Encoding; 130 llvm::SpecificBumpPtrAllocator<FormatToken> &Allocator; 131 // Index (in 'Tokens') of the last token that starts a new line. 132 unsigned FirstInLineIndex; 133 SmallVector<FormatToken *, 16> Tokens; 134 135 llvm::SmallMapVector<IdentifierInfo *, TokenType, 8> Macros; 136 137 llvm::SmallPtrSet<IdentifierInfo *, 8> TypeNames; 138 139 bool FormattingDisabled; 140 141 llvm::Regex MacroBlockBeginRegex; 142 llvm::Regex MacroBlockEndRegex; 143 144 // Targets that may appear inside a C# attribute. 145 static const llvm::StringSet<> CSharpAttributeTargets; 146 147 /// Handle Verilog-specific tokens. 148 bool readRawTokenVerilogSpecific(Token &Tok); 149 150 void readRawToken(FormatToken &Tok); 151 152 void resetLexer(unsigned Offset); 153 }; 154 155 } // namespace format 156 } // namespace clang 157 158 #endif 159