1 | """data_lang/htm8.py
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2 |
|
3 | TODO
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4 |
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5 | - would be nice: migrate everything off of TagLexer()
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6 | - oils_doc.py and help_gen.py
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7 | - this old API is stateful and uses Python iterators, which is problematic
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8 | - maybe we can use a better CSS selector abstraction
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9 |
|
10 | API:
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11 | - Get rid of Reset()?
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12 |
|
13 | Features:
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14 |
|
15 | - work on ToXml() test cases? This is another text of AttrLexer
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16 |
|
17 | Docs:
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18 |
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19 | - Copy all errors into doc/ref/chap-errors.md
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20 | - This helps understand the language
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21 |
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22 | C++:
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23 | - UTF-8 check, like JSON8
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24 | - re2c
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25 | - port lexer, which will fix static typing issues
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26 | - the abstraction needs to support submatch?
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27 | - for finding the end of a tag, etc.?
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28 | - and what about no match?
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29 |
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30 | - harmonize LexError and ParseError with data_lang/j8.py, which uses
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31 | error.Decode(msg, ..., cur_line_num)
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32 | """
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33 |
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34 | import re
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35 |
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36 | from typing import Dict, List, Tuple, Optional, IO, Any
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37 |
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38 | from _devbuild.gen.htm8_asdl import (h8_id, h8_id_t, attr_name, attr_name_t,
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39 | attr_name_str, attr_value_e, attr_value_t,
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40 | h8_val_id)
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41 | from doctools.util import log
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42 |
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43 |
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44 | class LexError(Exception):
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45 | """
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46 | Examples of lex errors:
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47 |
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48 | - h8_id.Invalid, like <> or &&
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49 | - Unclosed <!-- <? <![CDATA[ <script> <style>
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50 | """
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51 |
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52 | def __init__(self, msg, code_str, start_pos):
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53 | # type: (str, str, int) -> None
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54 | self.msg = msg
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55 | self.code_str = code_str
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56 | self.start_pos = start_pos
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57 |
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58 | def __str__(self):
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59 | # type: () -> str
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60 | return '(LexError %r %r)' % (
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61 | self.msg, self.code_str[self.start_pos:self.start_pos + 20])
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62 |
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63 |
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64 | def _FindLineNum(s, error_pos):
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65 | # type: (str, int) -> int
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66 | current_pos = 0
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67 | line_num = 1
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68 | while True:
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69 | newline_pos = s.find('\n', current_pos)
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70 | #log('current = %d, N %d, line %d', current_pos, newline_pos, line_num)
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71 |
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72 | if newline_pos == -1: # this is the last line
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73 | return line_num
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74 | if newline_pos >= error_pos:
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75 | return line_num
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76 | line_num += 1
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77 | current_pos = newline_pos + 1
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78 |
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79 |
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80 | class ParseError(Exception):
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81 | """
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82 | Examples of parse errors
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83 |
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84 | - unbalanced tag structure
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85 | - ul_table.py errors
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86 | """
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87 |
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88 | def __init__(self, msg, s=None, start_pos=-1):
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89 | # type: (str, Optional[str], int) -> None
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90 | self.msg = msg
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91 | self.s = s
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92 | self.start_pos = start_pos
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93 |
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94 | def __str__(self):
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95 | # type: () -> str
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96 | if self.s is not None:
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97 | assert self.start_pos != -1, self.start_pos
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98 | snippet = (self.s[self.start_pos:self.start_pos + 20])
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99 |
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100 | line_num = _FindLineNum(self.s, self.start_pos)
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101 | else:
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102 | snippet = ''
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103 | line_num = -1
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104 | msg = 'line %d: %r %r' % (line_num, self.msg, snippet)
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105 | return msg
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106 |
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107 |
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108 | class Output(object):
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109 | """Output for sed-like "replacement" model.
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110 |
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111 | Takes an underlying input buffer and an output file. Maintains a position
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112 | in the input buffer.
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113 |
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114 | Print FROM the input or print new text to the output.
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115 | """
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116 |
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117 | def __init__(self, s, f, left_pos=0, right_pos=-1):
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118 | # type: (str, IO[str], int, int) -> None
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119 | self.s = s
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120 | self.f = f
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121 | self.pos = left_pos
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122 | self.right_pos = len(s) if right_pos == -1 else right_pos
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123 |
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124 | def SkipTo(self, pos):
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125 | # type: (int) -> None
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126 | """Skip to a position."""
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127 | self.pos = pos
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128 |
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129 | def PrintUntil(self, pos):
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130 | # type: (int) -> None
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131 | """Print until a position."""
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132 | piece = self.s[self.pos:pos]
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133 | self.f.write(piece)
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134 | self.pos = pos
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135 |
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136 | def PrintTheRest(self):
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137 | # type: () -> None
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138 | """Print until the end of the string."""
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139 | self.PrintUntil(self.right_pos)
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140 |
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141 | def Print(self, s):
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142 | # type: (str) -> None
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143 | """Print text to the underlying buffer."""
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144 | self.f.write(s)
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145 |
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146 |
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147 | def MakeLexer(rules):
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148 | return [(re.compile(pat, re.VERBOSE), i) for (pat, i) in rules]
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149 |
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150 |
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151 | #
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152 | # Lexers
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153 | #
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154 |
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155 | _NAME_RE = r'[a-zA-Z][a-zA-Z0-9:_\-]*' # must start with letter
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156 |
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157 | CHAR_LEX = [
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158 | # Characters
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159 | # https://www.w3.org/TR/xml/#sec-references
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160 | (r'&\# [0-9]+ ;', h8_id.DecChar),
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161 | (r'&\# x[0-9a-fA-F]+ ;', h8_id.HexChar),
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162 | # TODO: shouldn't use _NAME_RE? Just letters
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163 | (r'& %s ;' % _NAME_RE, h8_id.CharEntity),
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164 | # Allow unquoted, and quoted
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165 | (r'&', h8_id.BadAmpersand),
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166 | ]
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167 |
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168 | HTM8_LEX = CHAR_LEX + [
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169 | # TODO: CommentBegin, ProcessingBegin, CDataBegin could have an additional
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170 | # action associated with them? The ending substring
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171 | (r'<!--', h8_id.CommentBegin),
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172 |
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173 | # Processing instruction are used for the XML header:
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174 | # <?xml version="1.0" encoding="UTF-8"?>
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175 | # They are technically XML-only, but in HTML5, they are another kind of
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176 | # comment:
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177 | #
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178 | # https://developer.mozilla.org/en-US/docs/Web/API/ProcessingInstruction
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179 | #
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180 | (r'<\?', h8_id.ProcessingBegin),
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181 | # Not necessary in HTML5, but occurs in XML
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182 | (r'<!\[CDATA\[', h8_id.CDataBegin), # <![CDATA[
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183 |
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184 | # Markup declarations
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185 | # - In HTML5, there is only <!DOCTYPE html>
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186 | # - XML has 4 more declarations: <!ELEMENT ...> ATTLIST ENTITY NOTATION
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187 | # - these seem to be part of DTD
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188 | # - it's useful to skip these, and be able to parse the rest of the document
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189 | # - Note: < is allowed?
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190 | (r'<! [^>\x00]+ >', h8_id.Decl),
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191 |
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192 | # Tags
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193 | # Notes:
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194 | # - We look for a valid tag name, but we don't validate attributes.
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195 | # That's done in the tag lexer.
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196 | # - We don't allow leading whitespace
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197 | (r'</ (%s) >' % _NAME_RE, h8_id.EndTag),
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198 | # self-closing <br/> comes before StartTag
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199 | # could/should these be collapsed into one rule?
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200 | (r'< (%s) [^>\x00]* />' % _NAME_RE, h8_id.StartEndTag), # end </a>
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201 | (r'< (%s) [^>\x00]* >' % _NAME_RE, h8_id.StartTag), # start <a>
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202 |
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203 | # HTML5 allows unescaped > in raw data, but < is not allowed.
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204 | # https://stackoverflow.com/questions/10462348/right-angle-bracket-in-html
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205 | #
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206 | # - My early blog has THREE errors when disallowing >
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207 | # - So do some .wwz files
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208 | (r'[^&<>\x00]+', h8_id.RawData),
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209 | (r'>', h8_id.BadGreaterThan),
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210 | # NUL is the end, an accomodation for re2c. Like we do in frontend/match.
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211 | (r'\x00', h8_id.EndOfStream),
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212 | # This includes < - it is not BadLessThan because it's NOT recoverable
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213 | (r'.', h8_id.Invalid),
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214 | ]
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215 |
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216 | # Old notes:
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217 | #
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218 | # Non-greedy matches are regular and can be matched in linear time
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219 | # with RE2.
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220 | #
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221 | # https://news.ycombinator.com/item?id=27099798
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222 | #
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223 |
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224 | # This person tried to do it with a regex:
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225 | #
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226 | # https://skeptric.com/html-comment-regexp/index.html
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227 |
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228 | # . is any char except newline
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229 | # https://re2c.org/manual/manual_c.html
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230 |
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231 | # Discarded options
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232 | #(r'<!-- .*? -->', h8_id.Comment),
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233 |
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234 | # Hack from Claude: \s\S instead of re.DOTALL. I don't like this
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235 | #(r'<!-- [\s\S]*? -->', h8_id.Comment),
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236 | #(r'<!-- (?:.|[\n])*? -->', h8_id.Comment),
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237 |
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238 | HTM8_LEX_COMPILED = MakeLexer(HTM8_LEX)
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239 |
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240 |
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241 | class Lexer(object):
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242 |
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243 | def __init__(self, s, left_pos=0, right_pos=-1, no_special_tags=False):
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244 | # type: (str, int, int, bool) -> None
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245 | self.s = s
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246 | self.pos = left_pos
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247 | self.right_pos = len(s) if right_pos == -1 else right_pos
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248 | self.no_special_tags = no_special_tags
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249 |
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250 | # string -> compiled regex pattern object
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251 | self.cache = {} # type: Dict[str, Any]
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252 |
|
253 | # either </script> or </style> - we search until we see that
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254 | self.search_state = None # type: Optional[str]
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255 |
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256 | # Position of tag name, if applicable
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257 | # - Set after you get a StartTag, EndTag, or StartEndTag
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258 | # - Unset on other tags
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259 | self.tag_pos_left = -1
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260 | self.tag_pos_right = -1
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261 |
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262 | def _Read(self):
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263 | # type: () -> Tuple[h8_id_t, int]
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264 | if self.pos == self.right_pos:
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265 | return h8_id.EndOfStream, self.pos
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266 |
|
267 | assert self.pos < self.right_pos, self.pos
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268 |
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269 | if self.search_state is not None and not self.no_special_tags:
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270 | # TODO: case-insensitive search for </SCRIPT> <SCRipt> ?
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271 | #
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272 | # Another strategy: enter a mode where we find ONLY the end tag
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273 | # regex, and any data that's not <, and then check the canonical
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274 | # tag name for 'script' or 'style'.
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275 | pos = self.s.find(self.search_state, self.pos)
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276 | if pos == -1:
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277 | raise LexError('Unterminated <script> or <style>', self.s,
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278 | self.pos)
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279 | self.search_state = None
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280 | # beginning
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281 | return h8_id.HtmlCData, pos
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282 |
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283 | # Find the first match.
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284 | # Note: frontend/match.py uses _LongestMatch(), which is different!
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285 | # TODO: reconcile them. This lexer should be expressible in re2c.
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286 |
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287 | for pat, tok_id in HTM8_LEX_COMPILED:
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288 | m = pat.match(self.s, self.pos)
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289 | if m:
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290 | if tok_id in (h8_id.StartTag, h8_id.EndTag, h8_id.StartEndTag):
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291 | self.tag_pos_left = m.start(1)
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292 | self.tag_pos_right = m.end(1)
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293 | else:
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294 | # Reset state
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295 | self.tag_pos_left = -1
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296 | self.tag_pos_right = -1
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297 |
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298 | if tok_id == h8_id.CommentBegin:
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299 | pos = self.s.find('-->', self.pos)
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300 | if pos == -1:
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301 | raise LexError('Unterminated <!--', self.s, self.pos)
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302 | return h8_id.Comment, pos + 3 # -->
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303 |
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304 | if tok_id == h8_id.ProcessingBegin:
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305 | pos = self.s.find('?>', self.pos)
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306 | if pos == -1:
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307 | raise LexError('Unterminated <?', self.s, self.pos)
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308 | return h8_id.Processing, pos + 2 # ?>
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309 |
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310 | if tok_id == h8_id.CDataBegin:
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311 | pos = self.s.find(']]>', self.pos)
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312 | if pos == -1:
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313 | # unterminated <![CDATA[
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314 | raise LexError('Unterminated <![CDATA[', self.s,
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315 | self.pos)
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316 | return h8_id.CData, pos + 3 # ]]>
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317 |
|
318 | if tok_id == h8_id.StartTag:
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319 | # TODO: reduce allocations
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320 | if (self.TagNameEquals('script') or
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321 | self.TagNameEquals('style')):
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322 | # <SCRipt a=b> -> </SCRipt>
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323 | self.search_state = '</' + self._LiteralTagName() + '>'
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324 |
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325 | return tok_id, m.end()
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326 | else:
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327 | raise AssertionError('h8_id.Invalid rule should have matched')
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328 |
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329 | def TagNamePos(self):
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330 | # type: () -> int
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331 | """The right position of the tag pos"""
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332 | assert self.tag_pos_right != -1, self.tag_pos_right
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333 | return self.tag_pos_right
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334 |
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335 | def TagNameEquals(self, expected):
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336 | # type: (str) -> bool
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337 | assert self.tag_pos_left != -1, self.tag_pos_left
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338 | assert self.tag_pos_right != -1, self.tag_pos_right
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339 |
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340 | # TODO: In C++, this does not need an allocation. Can we test
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341 | # directly?
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342 | return expected == self.CanonicalTagName()
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343 |
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344 | def _LiteralTagName(self):
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345 | # type: () -> str
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346 | assert self.tag_pos_left != -1, self.tag_pos_left
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347 | assert self.tag_pos_right != -1, self.tag_pos_right
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348 |
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349 | return self.s[self.tag_pos_left:self.tag_pos_right]
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350 |
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351 | def CanonicalTagName(self):
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352 | # type: () -> str
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353 | tag_name = self._LiteralTagName()
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354 | # Most tags are already lower case, so avoid allocation with this conditional
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355 | # TODO: this could go in the mycpp runtime?
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356 | if tag_name.islower():
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357 | return tag_name
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358 | else:
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359 | return tag_name.lower()
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360 |
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361 | def Read(self):
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362 | # type: () -> Tuple[h8_id_t, int]
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363 | tok_id, end_pos = self._Read()
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364 | self.pos = end_pos # advance
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365 | return tok_id, end_pos
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366 |
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367 | def LookAhead(self, regex):
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368 | # type: (str) -> bool
|
369 | """
|
370 | Currently used for ul_table.py. But taking a dynamic regex string is
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371 | not the right interface.
|
372 | """
|
373 | # Cache the regex compilation. This could also be LookAheadFor(THEAD)
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374 | # or something.
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375 | pat = self.cache.get(regex)
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376 | if pat is None:
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377 | pat = re.compile(regex)
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378 | self.cache[regex] = pat
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379 |
|
380 | m = pat.match(self.s, self.pos)
|
381 | return m is not None
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382 |
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383 |
|
384 | A_NAME_LEX = [
|
385 | # Leading whitespace is required, to separate attributes.
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386 | #
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387 | # If the = is not present, then we set the lexer in a state for
|
388 | # attr_value_e.Missing.
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389 | (r'\s+ (%s) \s* (=)? \s*' % _NAME_RE, attr_name.Ok),
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390 | # unexpected EOF
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391 |
|
392 | # The closing > or /> is treated as end of stream, and it's not an error.
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393 | (r'\s* /? >', attr_name.Done),
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394 |
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395 | # NUL should not be possible, because the top-level
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396 |
|
397 | # This includes < - it is not BadLessThan because it's NOT recoverable
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398 | (r'.', attr_name.Invalid),
|
399 | ]
|
400 |
|
401 | A_NAME_LEX_COMPILED = MakeLexer(A_NAME_LEX)
|
402 |
|
403 | # Here we just loop on regular tokens
|
404 | #
|
405 | # Examples:
|
406 | # <a href = unquoted&foo >
|
407 | # <a href = unquoted&foo > # BadAmpersand is allowed I guess
|
408 | # <a href ="unquoted&foo" > # double quoted
|
409 | # <a href ='unquoted&foo' > # single quoted
|
410 | # <a href = what"foo" > # HTML5 allows this, but we could disallow it if
|
411 | # it's not common. It opens up the j"" and $"" extensions
|
412 | # <a href = what'foo' > # ditto
|
413 |
|
414 | _UNQUOTED_VALUE = r'''[^ \t\r\n<>&"'\x00]+'''
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415 |
|
416 | # What comes after = ?
|
417 | A_VALUE_LEX = [
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418 | (r'"', h8_val_id.DoubleQuote),
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419 | (r"'", h8_val_id.SingleQuote),
|
420 | (_UNQUOTED_VALUE, h8_val_id.UnquotedVal),
|
421 | (r'.', h8_val_id.NoMatch),
|
422 | ]
|
423 |
|
424 | A_VALUE_LEX_COMPILED = MakeLexer(A_VALUE_LEX)
|
425 |
|
426 | # What's inside "" or '' ?
|
427 | QUOTED_VALUE_LEX = CHAR_LEX + [
|
428 | (r'"', h8_id.DoubleQuote),
|
429 | (r"'", h8_id.SingleQuote),
|
430 | (r'<', h8_id.BadLessThan), # BadAmpersand is in CharLex
|
431 |
|
432 | # TODO: think about whitespace for efficient class= queries?
|
433 | #(r'[ \r\n\t]', h8_id.Whitespace), # terminates unquoted values
|
434 | (r'''[^"'<>&\x00]+''', h8_id.RawData),
|
435 | # This includes > - it is not BadGreaterThan because it's NOT recoverable
|
436 | (r'.', h8_id.Invalid),
|
437 | ]
|
438 |
|
439 | QUOTED_VALUE_LEX_COMPILED = MakeLexer(QUOTED_VALUE_LEX)
|
440 |
|
441 |
|
442 | class AttrLexer(object):
|
443 | """
|
444 | Typical usage:
|
445 |
|
446 | while True:
|
447 | n, start_pos, end_pos = attr_lx.ReadName()
|
448 | if n == attr_name.Ok:
|
449 | if attr_lx.AttrNameEquals('div'):
|
450 | print('div')
|
451 |
|
452 | # TODO: also pass Optional[List[]] out_tokens?
|
453 | v, start_pos, end_pos = attr_lx.ReadValue()
|
454 | """
|
455 |
|
456 | def __init__(self, s):
|
457 | # type: (str) -> None
|
458 | self.s = s
|
459 |
|
460 | self.tok_id = h8_id.Invalid # Uninitialized
|
461 | self.tag_name_pos = -1 # Invalid
|
462 | self.tag_end_pos = -1
|
463 | self.must_not_exceed_pos = -1
|
464 |
|
465 | self.pos = -1
|
466 |
|
467 | self.name_start = -1
|
468 | self.name_end = -1
|
469 | self.equal_end = -1
|
470 | self.next_value_is_missing = False
|
471 |
|
472 | self.init_t = -1
|
473 | self.init_e = -1
|
474 |
|
475 | def Init(self, tok_id, tag_name_pos, end_pos):
|
476 | # type: (h8_id_t, int, int) -> None
|
477 | """Initialize so we can read names and values.
|
478 |
|
479 | Example:
|
480 | 'x <a y>' # tag_name_pos=4, end_pos=6
|
481 | 'x <a>' # tag_name_pos=4, end_pos=4
|
482 |
|
483 | The Init() method is used to reuse instances of the AttrLexer object.
|
484 | """
|
485 | assert tag_name_pos >= 0, tag_name_pos
|
486 | assert end_pos >= 0, end_pos
|
487 |
|
488 | #log('TAG NAME POS %d', tag_name_pos)
|
489 |
|
490 | self.tok_id = tok_id
|
491 | self.tag_name_pos = tag_name_pos
|
492 | self.end_pos = end_pos
|
493 |
|
494 | # Check for ambiguous <img src=/>
|
495 | if tok_id == h8_id.StartTag:
|
496 | self.must_not_exceed_pos = end_pos - 1 # account for >
|
497 | elif tok_id == h8_id.StartEndTag:
|
498 | self.must_not_exceed_pos = end_pos - 2 # account for />
|
499 | else:
|
500 | raise AssertionError(tok_id)
|
501 |
|
502 | self.pos = tag_name_pos
|
503 |
|
504 | # For Reset()
|
505 | self.init_t = tag_name_pos
|
506 | self.init_e = end_pos
|
507 |
|
508 | def Reset(self):
|
509 | # type: () -> None
|
510 |
|
511 | # TODO: maybe GetAttrRaw() should call this directly? But not any of
|
512 | # the AllAttrs() methods?
|
513 | self.tag_name_pos = self.init_t
|
514 | self.end_pos = self.init_e
|
515 | self.pos = self.init_t
|
516 |
|
517 | def ReadName(self):
|
518 | # type: () -> Tuple[attr_name_t, int, int, int]
|
519 | """Reads the attribute name
|
520 |
|
521 | EOF case:
|
522 | <a>
|
523 | <a >
|
524 |
|
525 | Error case:
|
526 | <a !>
|
527 | <a foo=bar !>
|
528 | """
|
529 | for pat, a in A_NAME_LEX_COMPILED:
|
530 | m = pat.match(self.s, self.pos)
|
531 | #log('ReadName() matching %r at %d', self.s, self.pos)
|
532 | if m:
|
533 | #log('ReadName() tag_name_pos %d pos, %d %s', self.tag_name_pos, self.pos, m.groups())
|
534 | if a == attr_name.Invalid:
|
535 | #log('m.groups %s', m.groups())
|
536 | return attr_name.Invalid, -1, -1, -1
|
537 |
|
538 | self.pos = m.end(0) # Advance if it's not invalid
|
539 |
|
540 | if a == attr_name.Ok:
|
541 | #log('%r', m.groups())
|
542 | self.name_start = m.start(1)
|
543 | self.name_end = m.end(1)
|
544 | self.equal_end = m.end(0) # XML conversion needs this
|
545 | # Is the equals sign missing? Set state.
|
546 | if m.group(2) is None:
|
547 | self.next_value_is_missing = True
|
548 | # HACK: REWIND, since we don't want to consume whitespace
|
549 | self.pos = self.name_end
|
550 | else:
|
551 | self.next_value_is_missing = False
|
552 | return attr_name.Ok, self.name_start, self.name_end, self.equal_end
|
553 | else:
|
554 | # Reset state - e.g. you must call AttrNameEquals
|
555 | self.name_start = -1
|
556 | self.name_end = -1
|
557 |
|
558 | if a == attr_name.Done:
|
559 | return attr_name.Done, -1, -1, -1
|
560 | else:
|
561 | context = self.s[self.pos:]
|
562 | #log('s %r %d', self.s, self.pos)
|
563 | raise AssertionError('h8_id.Invalid rule should have matched %r' %
|
564 | context)
|
565 |
|
566 | def _CanonicalAttrName(self):
|
567 | # type: () -> str
|
568 | """Return the lower case attribute name.
|
569 |
|
570 | Must call after ReadName()
|
571 | """
|
572 | assert self.name_start >= 0, self.name_start
|
573 | assert self.name_end >= 0, self.name_end
|
574 |
|
575 | attr_name = self.s[self.name_start:self.name_end]
|
576 | if attr_name.islower():
|
577 | return attr_name
|
578 | else:
|
579 | return attr_name.lower()
|
580 |
|
581 | def AttrNameEquals(self, expected):
|
582 | # type: (str) -> bool
|
583 | """
|
584 | Must call after ReadName()
|
585 |
|
586 | TODO: This can be optimized to be "in place", with zero allocs.
|
587 | """
|
588 | return expected == self._CanonicalAttrName()
|
589 |
|
590 | def _QuotedRead(self):
|
591 | # type: () -> Tuple[h8_id_t, int]
|
592 |
|
593 | for pat, tok_id in QUOTED_VALUE_LEX_COMPILED:
|
594 | # BUG: We can OVER-READ what the segement lexer gave us, e.g. with
|
595 | # <a href=">"> - the inside > ends it
|
596 | m = pat.match(self.s, self.pos)
|
597 | if m:
|
598 | end_pos = m.end(0) # Advance
|
599 | #log('_QuotedRead %r', self.s[self.pos:end_pos])
|
600 | return tok_id, end_pos
|
601 | else:
|
602 | context = self.s[self.pos:self.pos + 10]
|
603 | raise AssertionError('h8_id.Invalid rule should have matched %r' %
|
604 | context)
|
605 |
|
606 | def ReadValue(self, tokens_out=None):
|
607 | # type: (Optional[List[Tuple[h8_id, int]]]) -> Tuple[attr_value_t, int, int]
|
608 | """Read the attribute value.
|
609 |
|
610 | In general, it is escaped or "raw"
|
611 |
|
612 | Can only be called after a SUCCESSFUL ReadName().
|
613 | Assuming ReadName() returned a value, this should NOT fail.
|
614 | """
|
615 | # ReadName() invariant
|
616 | assert self.name_start >= 0, self.name_start
|
617 | assert self.name_end >= 0, self.name_end
|
618 |
|
619 | self.name_start = -1
|
620 | self.name_end = -1
|
621 |
|
622 | if self.next_value_is_missing:
|
623 | # Do not advance self.pos
|
624 | #log('-> MISSING pos %d : %r', self.pos, self.s[self.pos:])
|
625 | return attr_value_e.Missing, -1, -1
|
626 |
|
627 | # Now read " ', unquoted or empty= is valid too.
|
628 | for pat, a in A_VALUE_LEX_COMPILED:
|
629 | m = pat.match(self.s, self.pos)
|
630 | if m:
|
631 | first_end_pos = m.end(0)
|
632 | # We shouldn't go past the end
|
633 | assert first_end_pos <= self.end_pos, \
|
634 | 'first_end_pos = %d should be less than self.end_pos = %d' % (first_end_pos, self.end_pos)
|
635 | #log('m %s', m.groups())
|
636 |
|
637 | # Note: Unquoted value can't contain & etc. now, so there
|
638 | # is no unquoting, and no respecting tokens_raw.
|
639 | if a == h8_val_id.UnquotedVal:
|
640 | if first_end_pos > self.must_not_exceed_pos:
|
641 | #log('first_end_pos %d', first_end_pos)
|
642 | #log('must_not_exceed_pos %d', self.must_not_exceed_pos)
|
643 | raise LexError(
|
644 | 'Ambiguous slash: last attribute should be quoted',
|
645 | self.s, first_end_pos)
|
646 | self.pos = first_end_pos # Advance
|
647 | return attr_value_e.Unquoted, m.start(0), first_end_pos
|
648 |
|
649 | # TODO: respect tokens_out
|
650 | if a == h8_val_id.DoubleQuote:
|
651 | self.pos = first_end_pos
|
652 | while True:
|
653 | tok_id, q_end_pos = self._QuotedRead()
|
654 | #log('self.pos %d q_end_pos %d', self.pos, q_end_pos)
|
655 | if tok_id == h8_id.Invalid:
|
656 | raise LexError(
|
657 | 'ReadValue() got invalid token (DQ)', self.s,
|
658 | self.pos)
|
659 | if tok_id == h8_id.DoubleQuote:
|
660 | right_pos = self.pos
|
661 | self.pos = q_end_pos # Advance past "
|
662 | return attr_value_e.DoubleQuoted, first_end_pos, right_pos
|
663 | self.pos = q_end_pos # Advance _QuotedRead
|
664 |
|
665 | # TODO: respect tokens_out
|
666 | if a == h8_val_id.SingleQuote:
|
667 | self.pos = first_end_pos
|
668 | while True:
|
669 | tok_id, q_end_pos = self._QuotedRead()
|
670 | if tok_id == h8_id.Invalid:
|
671 | raise LexError(
|
672 | 'ReadValue() got invalid token (SQ)', self.s,
|
673 | self.pos)
|
674 | if tok_id == h8_id.SingleQuote:
|
675 | right_pos = self.pos
|
676 | self.pos = q_end_pos # Advance past "
|
677 | return attr_value_e.SingleQuoted, first_end_pos, right_pos
|
678 | self.pos = q_end_pos # Advance _QuotedRead
|
679 |
|
680 | if a == h8_val_id.NoMatch:
|
681 | # <a foo = >
|
682 | return attr_value_e.Empty, -1, -1
|
683 | else:
|
684 | raise AssertionError('h8_val_id.NoMatch rule should have matched')
|
685 |
|
686 |
|
687 | def GetAttrRaw(attr_lx, name):
|
688 | # type: (AttrLexer, str) -> Optional[str]
|
689 | while True:
|
690 | n, name_start, name_end, _ = attr_lx.ReadName()
|
691 | #log('==> ReadName %s %d %d', attr_name_str(n), name_start, name_end)
|
692 | if n == attr_name.Ok:
|
693 | if attr_lx.AttrNameEquals(name):
|
694 | v, val_start, val_end = attr_lx.ReadValue()
|
695 | return attr_lx.s[val_start:val_end]
|
696 | else:
|
697 | # Problem with stateful API: You are forced to either ReadValue()
|
698 | # or SkipVlaue()
|
699 | attr_lx.ReadValue()
|
700 | elif n == attr_name.Done:
|
701 | break
|
702 | elif n == attr_name.Invalid:
|
703 | raise LexError('GetAttrRaw() got invalid token', attr_lx.s,
|
704 | attr_lx.pos)
|
705 | else:
|
706 | raise AssertionError()
|
707 |
|
708 | return None
|
709 |
|
710 |
|
711 | def AllAttrsRawSlice(attr_lx):
|
712 | # type: (AttrLexer) -> List[Tuple[int, int, int, attr_value_t, int, int]]
|
713 | result = []
|
714 | while True:
|
715 | n, name_start, name_end, equal_end = attr_lx.ReadName()
|
716 | if 0:
|
717 | log(' AllAttrsRaw ==> ReadName %s %d %d %r', attr_name_str(n),
|
718 | name_start, name_end, attr_lx.s[attr_lx.pos:attr_lx.pos + 10])
|
719 | if n == attr_name.Ok:
|
720 | #name = attr_lx.s[name_start:name_end]
|
721 | #log(' Name %r', name)
|
722 |
|
723 | v, val_start, val_end = attr_lx.ReadValue()
|
724 | #val = attr_lx.s[val_start:val_end]
|
725 | #log(' ReadValue %r', val)
|
726 | result.append(
|
727 | (name_start, name_end, equal_end, v, val_start, val_end))
|
728 | elif n == attr_name.Done:
|
729 | break
|
730 | elif n == attr_name.Invalid:
|
731 | raise LexError('AllAttrsRaw() got invalid token', attr_lx.s,
|
732 | attr_lx.pos)
|
733 | else:
|
734 | raise AssertionError()
|
735 |
|
736 | return result
|
737 |
|
738 |
|
739 | def AllAttrsRaw(attr_lx):
|
740 | # type: (AttrLexer) -> List[Tuple[str, str]]
|
741 | """
|
742 | Get a list of pairs [('class', 'foo'), ('href', '?foo=1&bar=2')]
|
743 |
|
744 | The quoted values may be escaped. We would need another lexer to
|
745 | unescape them.
|
746 | """
|
747 | slices = AllAttrsRawSlice(attr_lx)
|
748 | pairs = []
|
749 | s = attr_lx.s
|
750 | for name_start, name_end, equal_end, val_id, val_start, val_end in slices:
|
751 | n = s[name_start:name_end]
|
752 | v = s[val_start:val_end]
|
753 | pairs.append((n, v))
|
754 | return pairs
|