1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
|
# frozen_string_literal: true
module Prism
module Translation
class Parser
# Accepts a list of prism tokens and converts them into the expected
# format for the parser gem.
class Lexer
# The direct translating of types between the two lexers.
TYPES = {
# These tokens should never appear in the output of the lexer.
EOF: nil,
MISSING: nil,
NOT_PROVIDED: nil,
IGNORED_NEWLINE: nil,
EMBDOC_END: nil,
EMBDOC_LINE: nil,
__END__: nil,
# These tokens have more or less direct mappings.
AMPERSAND: :tAMPER2,
AMPERSAND_AMPERSAND: :tANDOP,
AMPERSAND_AMPERSAND_EQUAL: :tOP_ASGN,
AMPERSAND_DOT: :tANDDOT,
AMPERSAND_EQUAL: :tOP_ASGN,
BACK_REFERENCE: :tBACK_REF,
BACKTICK: :tXSTRING_BEG,
BANG: :tBANG,
BANG_EQUAL: :tNEQ,
BANG_TILDE: :tNMATCH,
BRACE_LEFT: :tLCURLY,
BRACE_RIGHT: :tRCURLY,
BRACKET_LEFT: :tLBRACK2,
BRACKET_LEFT_ARRAY: :tLBRACK,
BRACKET_LEFT_RIGHT: :tAREF,
BRACKET_LEFT_RIGHT_EQUAL: :tASET,
BRACKET_RIGHT: :tRBRACK,
CARET: :tCARET,
CARET_EQUAL: :tOP_ASGN,
CHARACTER_LITERAL: :tCHARACTER,
CLASS_VARIABLE: :tCVAR,
COLON: :tCOLON,
COLON_COLON: :tCOLON2,
COMMA: :tCOMMA,
COMMENT: :tCOMMENT,
CONSTANT: :tCONSTANT,
DOT: :tDOT,
DOT_DOT: :tDOT2,
DOT_DOT_DOT: :tDOT3,
EMBDOC_BEGIN: :tCOMMENT,
EMBEXPR_BEGIN: :tSTRING_DBEG,
EMBEXPR_END: :tSTRING_DEND,
EMBVAR: :tSTRING_DVAR,
EQUAL: :tEQL,
EQUAL_EQUAL: :tEQ,
EQUAL_EQUAL_EQUAL: :tEQQ,
EQUAL_GREATER: :tASSOC,
EQUAL_TILDE: :tMATCH,
FLOAT: :tFLOAT,
FLOAT_IMAGINARY: :tIMAGINARY,
FLOAT_RATIONAL: :tRATIONAL,
FLOAT_RATIONAL_IMAGINARY: :tIMAGINARY,
GLOBAL_VARIABLE: :tGVAR,
GREATER: :tGT,
GREATER_EQUAL: :tGEQ,
GREATER_GREATER: :tRSHFT,
GREATER_GREATER_EQUAL: :tOP_ASGN,
HEREDOC_START: :tSTRING_BEG,
HEREDOC_END: :tSTRING_END,
IDENTIFIER: :tIDENTIFIER,
INSTANCE_VARIABLE: :tIVAR,
INTEGER: :tINTEGER,
INTEGER_IMAGINARY: :tIMAGINARY,
INTEGER_RATIONAL: :tRATIONAL,
INTEGER_RATIONAL_IMAGINARY: :tIMAGINARY,
KEYWORD_ALIAS: :kALIAS,
KEYWORD_AND: :kAND,
KEYWORD_BEGIN: :kBEGIN,
KEYWORD_BEGIN_UPCASE: :klBEGIN,
KEYWORD_BREAK: :kBREAK,
KEYWORD_CASE: :kCASE,
KEYWORD_CLASS: :kCLASS,
KEYWORD_DEF: :kDEF,
KEYWORD_DEFINED: :kDEFINED,
KEYWORD_DO: :kDO,
KEYWORD_DO_LOOP: :kDO_COND,
KEYWORD_END: :kEND,
KEYWORD_END_UPCASE: :klEND,
KEYWORD_ENSURE: :kENSURE,
KEYWORD_ELSE: :kELSE,
KEYWORD_ELSIF: :kELSIF,
KEYWORD_FALSE: :kFALSE,
KEYWORD_FOR: :kFOR,
KEYWORD_IF: :kIF,
KEYWORD_IF_MODIFIER: :kIF_MOD,
KEYWORD_IN: :kIN,
KEYWORD_MODULE: :kMODULE,
KEYWORD_NEXT: :kNEXT,
KEYWORD_NIL: :kNIL,
KEYWORD_NOT: :kNOT,
KEYWORD_OR: :kOR,
KEYWORD_REDO: :kREDO,
KEYWORD_RESCUE: :kRESCUE,
KEYWORD_RESCUE_MODIFIER: :kRESCUE_MOD,
KEYWORD_RETRY: :kRETRY,
KEYWORD_RETURN: :kRETURN,
KEYWORD_SELF: :kSELF,
KEYWORD_SUPER: :kSUPER,
KEYWORD_THEN: :kTHEN,
KEYWORD_TRUE: :kTRUE,
KEYWORD_UNDEF: :kUNDEF,
KEYWORD_UNLESS: :kUNLESS,
KEYWORD_UNLESS_MODIFIER: :kUNLESS_MOD,
KEYWORD_UNTIL: :kUNTIL,
KEYWORD_UNTIL_MODIFIER: :kUNTIL_MOD,
KEYWORD_WHEN: :kWHEN,
KEYWORD_WHILE: :kWHILE,
KEYWORD_WHILE_MODIFIER: :kWHILE_MOD,
KEYWORD_YIELD: :kYIELD,
KEYWORD___ENCODING__: :k__ENCODING__,
KEYWORD___FILE__: :k__FILE__,
KEYWORD___LINE__: :k__LINE__,
LABEL: :tLABEL,
LABEL_END: :tLABEL_END,
LAMBDA_BEGIN: :tLAMBEG,
LESS: :tLT,
LESS_EQUAL: :tLEQ,
LESS_EQUAL_GREATER: :tCMP,
LESS_LESS: :tLSHFT,
LESS_LESS_EQUAL: :tOP_ASGN,
METHOD_NAME: :tFID,
MINUS: :tMINUS,
MINUS_EQUAL: :tOP_ASGN,
MINUS_GREATER: :tLAMBDA,
NEWLINE: :tNL,
NUMBERED_REFERENCE: :tNTH_REF,
PARENTHESIS_LEFT: :tLPAREN,
PARENTHESIS_LEFT_PARENTHESES: :tLPAREN_ARG,
PARENTHESIS_RIGHT: :tRPAREN,
PERCENT: :tPERCENT,
PERCENT_EQUAL: :tOP_ASGN,
PERCENT_LOWER_I: :tQSYMBOLS_BEG,
PERCENT_LOWER_W: :tQWORDS_BEG,
PERCENT_UPPER_I: :tSYMBOLS_BEG,
PERCENT_UPPER_W: :tWORDS_BEG,
PERCENT_LOWER_X: :tXSTRING_BEG,
PLUS: :tPLUS,
PLUS_EQUAL: :tOP_ASGN,
PIPE_EQUAL: :tOP_ASGN,
PIPE: :tPIPE,
PIPE_PIPE: :tOROP,
PIPE_PIPE_EQUAL: :tOP_ASGN,
QUESTION_MARK: :tEH,
REGEXP_BEGIN: :tREGEXP_BEG,
REGEXP_END: :tSTRING_END,
SEMICOLON: :tSEMI,
SLASH: :tDIVIDE,
SLASH_EQUAL: :tOP_ASGN,
STAR: :tSTAR2,
STAR_EQUAL: :tOP_ASGN,
STAR_STAR: :tPOW,
STAR_STAR_EQUAL: :tOP_ASGN,
STRING_BEGIN: :tSTRING_BEG,
STRING_CONTENT: :tSTRING_CONTENT,
STRING_END: :tSTRING_END,
SYMBOL_BEGIN: :tSYMBEG,
TILDE: :tTILDE,
UAMPERSAND: :tAMPER,
UCOLON_COLON: :tCOLON3,
UDOT_DOT: :tBDOT2,
UDOT_DOT_DOT: :tBDOT3,
UMINUS: :tUMINUS,
UMINUS_NUM: :tUNARY_NUM,
UPLUS: :tUPLUS,
USTAR: :tSTAR,
USTAR_STAR: :tPOW,
WORDS_SEP: :tSPACE
}
# These constants represent flags in our lex state. We really, really
# don't want to be using them and we really, really don't want to be
# exposing them as part of our public API. Unfortunately, we don't have
# another way of matching the exact tokens that the parser gem expects
# without them. We should find another way to do this, but in the
# meantime we'll hide them from the documentation and mark them as
# private constants.
EXPR_BEG = 0x1 # :nodoc:
EXPR_LABEL = 0x400 # :nodoc:
private_constant :TYPES, :EXPR_BEG, :EXPR_LABEL
# The Parser::Source::Buffer that the tokens were lexed from.
attr_reader :source_buffer
# An array of tuples that contain prism tokens and their associated lex
# state when they were lexed.
attr_reader :lexed
# A hash that maps offsets in bytes to offsets in characters.
attr_reader :offset_cache
# Initialize the lexer with the given source buffer, prism tokens, and
# offset cache.
def initialize(source_buffer, lexed, offset_cache)
@source_buffer = source_buffer
@lexed = lexed
@offset_cache = offset_cache
end
Range = ::Parser::Source::Range # :nodoc:
private_constant :Range
# Convert the prism tokens into the expected format for the parser gem.
def to_a
tokens = []
index = 0
length = lexed.length
heredoc_identifier_stack = []
while index < length
token, state = lexed[index]
index += 1
next if %i[IGNORED_NEWLINE __END__ EOF].include?(token.type)
type = TYPES.fetch(token.type)
value = token.value
location = Range.new(source_buffer, offset_cache[token.location.start_offset], offset_cache[token.location.end_offset])
case type
when :tCHARACTER
value.delete_prefix!("?")
when :tCOMMENT
if token.type == :EMBDOC_BEGIN
start_index = index
while !((next_token = lexed[index][0]) && next_token.type == :EMBDOC_END) && (index < length - 1)
value += next_token.value
index += 1
end
if start_index != index
value += next_token.value
location = Range.new(source_buffer, offset_cache[token.location.start_offset], offset_cache[lexed[index][0].location.end_offset])
index += 1
end
else
value.chomp!
location = Range.new(source_buffer, offset_cache[token.location.start_offset], offset_cache[token.location.end_offset - 1])
end
when :tNL
value = nil
when :tFLOAT
value = parse_float(value)
when :tIMAGINARY
value = parse_complex(value)
when :tINTEGER
if value.start_with?("+")
tokens << [:tUNARY_NUM, ["+", Range.new(source_buffer, offset_cache[token.location.start_offset], offset_cache[token.location.start_offset + 1])]]
location = Range.new(source_buffer, offset_cache[token.location.start_offset + 1], offset_cache[token.location.end_offset])
end
value = parse_integer(value)
when :tLABEL
value.chomp!(":")
when :tLABEL_END
value.chomp!(":")
when :tLCURLY
type = :tLBRACE if state == EXPR_BEG | EXPR_LABEL
when :tNTH_REF
value = parse_integer(value.delete_prefix("$"))
when :tOP_ASGN
value.chomp!("=")
when :tRATIONAL
value = parse_rational(value)
when :tSPACE
value = nil
when :tSTRING_BEG
if token.type == :HEREDOC_START
heredoc_identifier_stack.push(value.match(/<<[-~]?["'`]?(?<heredoc_identifier>.*?)["'`]?\z/)[:heredoc_identifier])
end
if ["\"", "'"].include?(value) && (next_token = lexed[index][0]) && next_token.type == :STRING_END
next_location = token.location.join(next_token.location)
type = :tSTRING
value = ""
location = Range.new(source_buffer, offset_cache[next_location.start_offset], offset_cache[next_location.end_offset])
index += 1
elsif ["\"", "'"].include?(value) && (next_token = lexed[index][0]) && next_token.type == :STRING_CONTENT && next_token.value.lines.count <= 1 && (next_next_token = lexed[index + 1][0]) && next_next_token.type == :STRING_END
next_location = token.location.join(next_next_token.location)
type = :tSTRING
value = next_token.value.gsub("\\\\", "\\")
location = Range.new(source_buffer, offset_cache[next_location.start_offset], offset_cache[next_location.end_offset])
index += 2
elsif value.start_with?("<<")
quote = value[2] == "-" || value[2] == "~" ? value[3] : value[2]
if quote == "`"
type = :tXSTRING_BEG
value = "<<`"
else
value = "<<#{quote == "'" || quote == "\"" ? quote : "\""}"
end
end
when :tSTRING_CONTENT
unless (lines = token.value.lines).one?
start_offset = offset_cache[token.location.start_offset]
lines.map do |line|
newline = line.end_with?("\r\n") ? "\r\n" : "\n"
chomped_line = line.chomp
if match = chomped_line.match(/(?<backslashes>\\+)\z/)
adjustment = match[:backslashes].size / 2
adjusted_line = chomped_line.delete_suffix("\\" * adjustment)
if match[:backslashes].size.odd?
adjusted_line.delete_suffix!("\\")
adjustment += 2
else
adjusted_line << newline
end
else
adjusted_line = line
adjustment = 0
end
end_offset = start_offset + adjusted_line.length + adjustment
tokens << [:tSTRING_CONTENT, [adjusted_line, Range.new(source_buffer, offset_cache[start_offset], offset_cache[end_offset])]]
start_offset = end_offset
end
next
end
when :tSTRING_DVAR
value = nil
when :tSTRING_END
if token.type == :HEREDOC_END && value.end_with?("\n")
newline_length = value.end_with?("\r\n") ? 2 : 1
value = heredoc_identifier_stack.pop
location = Range.new(source_buffer, offset_cache[token.location.start_offset], offset_cache[token.location.end_offset - newline_length])
elsif token.type == :REGEXP_END
value = value[0]
location = Range.new(source_buffer, offset_cache[token.location.start_offset], offset_cache[token.location.start_offset + 1])
end
when :tSYMBEG
if (next_token = lexed[index][0]) && next_token.type != :STRING_CONTENT && next_token.type != :EMBEXPR_BEGIN && next_token.type != :EMBVAR
next_location = token.location.join(next_token.location)
type = :tSYMBOL
value = next_token.value
value = { "~@" => "~", "!@" => "!" }.fetch(value, value)
location = Range.new(source_buffer, offset_cache[next_location.start_offset], offset_cache[next_location.end_offset])
index += 1
end
when :tFID
if !tokens.empty? && tokens.dig(-1, 0) == :kDEF
type = :tIDENTIFIER
end
when :tXSTRING_BEG
if (next_token = lexed[index][0]) && next_token.type != :STRING_CONTENT && next_token.type != :STRING_END
type = :tBACK_REF2
end
end
tokens << [type, [value, location]]
if token.type == :REGEXP_END
tokens << [:tREGEXP_OPT, [token.value[1..], Range.new(source_buffer, offset_cache[token.location.start_offset + 1], offset_cache[token.location.end_offset])]]
end
end
tokens
end
private
# Parse an integer from the string representation.
def parse_integer(value)
Integer(value)
rescue ArgumentError
0
end
# Parse a float from the string representation.
def parse_float(value)
Float(value)
rescue ArgumentError
0.0
end
# Parse a complex from the string representation.
def parse_complex(value)
value.chomp!("i")
if value.end_with?("r")
Complex(0, parse_rational(value))
elsif value.start_with?(/0[BbOoDdXx]/)
Complex(0, parse_integer(value))
else
Complex(0, value)
end
rescue ArgumentError
0i
end
# Parse a rational from the string representation.
def parse_rational(value)
value.chomp!("r")
if value.start_with?(/0[BbOoDdXx]/)
Rational(parse_integer(value))
else
Rational(value)
end
rescue ArgumentError
0r
end
end
end
end
end
|