def create_core_grammar() -> Grammar:
""" This function is used for initialize default grammar """
grammar = Grammar()
grammar.add_pattern(grammar.add_token('Comment'), RE_COMMENT)
grammar.add_pattern(grammar.add_token('Whitespace'), RE_WHITESPACE)
grammar.add_pattern(grammar.add_token('Name'), RE_NAME)
grammar.add_pattern(grammar.add_token('NewLine'), RE_NEWLINE)
grammar.add_pattern(grammar.add_token('String'), RE_STRING_SINGLE)
grammar.add_pattern(grammar.add_token('String'), RE_STRING_DOUBLE)
grammar.add_pattern(grammar.add_token('Integer'), RE_NUMBER_BINARY)
grammar.add_pattern(grammar.add_token('Integer'), RE_NUMBER_OCTAL)
grammar.add_pattern(grammar.add_token('Integer'), RE_NUMBER_DECIMAL)
grammar.add_pattern(grammar.add_token('Integer'), RE_NUMBER_HEXADECIMAL)
grammar.add_pattern(grammar.add_token('Float'), RE_FLOAT_POINT)
grammar.add_pattern(grammar.add_token('Float'), RE_FLOAT_EXPONENT)
grammar.add_implicit('(')
grammar.add_implicit(')')
grammar.add_implicit('[')
grammar.add_implicit(']')
grammar.add_implicit('{')
grammar.add_implicit('}')
grammar.add_implicit('<')
grammar.add_implicit('>')
grammar.add_trivia(grammar.tokens['Comment'])
grammar.add_trivia(grammar.tokens['Whitespace'])
grammar.add_brackets(grammar.tokens['('], grammar.tokens[')'])
grammar.add_brackets(grammar.tokens['['], grammar.tokens[']'])
grammar.add_brackets(grammar.tokens['{'], grammar.tokens['}'])
return grammar
def test_add_brackets():
grammar = Grammar()
open_id = grammar.add_implicit('(')
close_id = grammar.add_implicit(')')
assert grammar.brackets == set()
assert grammar.open_brackets == set()
assert grammar.close_brackets == set()
grammar.add_brackets(open_id, close_id)
assert grammar.brackets == {(open_id, close_id)}
assert grammar.open_brackets == {open_id}
assert grammar.close_brackets == {close_id}
assert grammar.bracket_pairs[open_id] == close_id
def test_extend_brackets_grammar():
grammar1 = Grammar()
grammar1.add_brackets(grammar1.add_implicit('('),
grammar1.add_implicit(')'))
grammar2 = Grammar()
grammar2.add_brackets(grammar2.add_implicit('('),
grammar2.add_implicit(')'))
grammar2.add_brackets(grammar2.add_implicit('['),
grammar2.add_implicit(']'))
result = Grammar.merge(grammar1, grammar2)
assert result.brackets == {(result.tokens['['], result.tokens[']']),
(result.tokens['('], result.tokens[')'])}