def parse_line(text_line):
words = split_line(text_line.upper())
# empty line or comment line
if len(words) == 0 or text_line[0] == '*':
return None
# line without a label
if text_line[0].isspace():
words.insert(0, None)
if len(words) < 2:
raise MissingOperationError
# line without an operand
if len(words) < 3:
words.append(None)
label, operation, argument = words[0:3]
# check label
if label is not None:
if not SymbolTable.is_label(label):
raise InvalidLabelError(label)
if len(label) > 10:
raise TooLongLabelError(label)
# check operation
if not operations.is_valid_operation(operation):
raise UnknownOperationError(operation)
# check arg for directives
if operations.is_arg_required(operation) and argument is None:
raise ArgumentRequiredError(operation)
return Line(label, operation, argument)
def test_is_label(self):
for l in 'blah a z 123y321 1a1 a1 1a 123456789a 9H labellabel 40F 40B F B'.split():
self.assertEqual(SymbolTable.is_label(l), True)
for l in '4F 4B 0F 0B 9F 9B 123 1 2 label* # % label,'.split():
self.assertEqual(SymbolTable.is_label(l), False)
