def _split_on(span: Span, split: Set[str]) -> List[Span]:
start = 0
result: List[Span] = []
for i, c in enumerate(span.text() + list(split)[0]):
if c in split:
if i > start:
result.append(span[start:i])
start = i + 1
return result
def _character_literal(span: Span) -> int:
text = span.text()
if text.startswith('\\'):
if len(text) != 2 or text[1] not in escapes:
raise SingleParseError('Invalid escape sequence: "' + text + '"',
span)
return ord(escapes[text[1]])
else:
if len(text) > 1 or ord(text) >= 256:
raise SingleParseError('Invalid character literal: "' + text + '"',
span)
return ord(text)
def _line(span: Span, args: Args) -> List[Instruction]:
span = span.strip()
text = span.text()
if not text:
return []
code = _code(span)
if args.assertions and text[0] in ('=', '$'):
if code:
raise SingleParseError('Brainfuck code in assertion line', span)
if text[0] == '=':
return [_tape_assertion(span)]
elif text[0] == '$':
return [_test_input(span)]
else:
assert False, 'unreachable'
else:
return code
def _matcher(span: Span) -> Matcher:
text = span.text()
if text.startswith('!'):
return InverseMatcher(_matcher(span[1:]))
if text == '*':
return WildcardMatcher()
if text.startswith('@'):
return LiteralMatcher(text, _character_literal(span[1:]))
number_matches = re.findall('^[0-9]+$', text)
if number_matches:
value = int(text)
if value < 0 or value >= 256:
raise SingleParseError(
'Invalid cell value ' + str(value) +
', must be in range 0-255', span)
return LiteralMatcher(text, int(text))
ident_matches = re.findall('^[a-zA-Z_][a-zA-Z_0-9]*$', text)
if ident_matches:
return VariableMatcher(text)
raise SingleParseError('Invalid assertion cell: "' + text + '"', span)
def _code(span: Span) -> List[Instruction]:
code: List[Instruction] = []
for i, c in enumerate(span.text()):
if c in op_set:
code.append(Op(c, span[i:i + 1]))
return code