def get_control_characters(message, characters=None):
u"""Read the UNA segment from the passed string.
:param message: a valid EDI message string, or UNA segment string,
to extract the control characters from
:param characters: the control characters to use, if none found in
the message
:rtype: str or None
:return: the control characters
"""
if not characters:
characters = Characters()
# First, try to read the UNA segment ("Service String Advice",
# conditional). This segment and the UNB segment (Interchange Header)
# must always be written in ASCII, even if after the BGM the files
# continues with cyrillic or UTF-16.
# If it does not exist, return a default.
if not message[:3] == u"UNA":
return characters
# Get the character definitions
chars = message[3:9]
characters.is_extracted_from_message = True
characters.component_separator = chars[0]
characters.data_separator = chars[1]
characters.decimal_point = chars[2]
characters.escape_character = chars[3]
characters.reserved_character = chars[4]
characters.segment_terminator = chars[5]
return characters
def test_cc_assigning():
one = Characters()
one.component_separator = "x"
assert one.component_separator == "x"
assert one == "x+,? '"
def test_cc_assigning(self):
one = Characters()
one.component_separator = 'x'
self.assertEqual(one.component_separator, 'x')
self.assertEqual(str(one), "x+,? '")