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#!/usr/bin/env python
"""parser.py - A JavaScript parser, currently with many bugs.
See README.md for instructions.
"""
from . import parser_tables
from .lexer import JSLexer
# "type: ignore" because mypy can't see inside js_parser.parser_tables.
class JSParser(parser_tables.Parser): # type: ignore
def __init__(self, goal='Script', builder=None):
super().__init__(goal, builder)
self._goal = goal
def clone(self):
return JSParser(self._goal, self.methods)
def on_recover(self, error_code, lexer, stv):
"""Check that ASI error recovery is really acceptable."""
if error_code == 'asi':
# ASI is allowed in three places:
# - at the end of the source text
# - before a close brace `}`
# - after a LineTerminator
# Hence the three-part if-condition below.
#
# The other quirks of ASI are implemented by massaging the syntax,
# in parse_esgrammar.py.
if not self.closed and stv.term != '}' and not lexer.saw_line_terminator():
lexer.throw("missing semicolon")
else:
# ASI is always allowed in this one state.
assert error_code == 'do_while_asi'
def parse_Script(text):
lexer = JSLexer(JSParser('Script'))
lexer.write(text)
return lexer.close()