def test_identity(self):
value = "0221"
self.assertEqual(undefined_to_string(string_to_undefined(value)),
value)
value = "48 50 50 49"
self.assertEqual(string_to_undefined(undefined_to_string(value)),
value)
def test_undefined_to_string(self):
self.assertEqual(undefined_to_string("48 50 50 49"), "0221")
self.assertEqual(undefined_to_string("48 50 50 49 "), "0221")
self.assertRaises(ValueError, undefined_to_string, "")
self.assertRaises(ValueError, undefined_to_string, "foo")
self.assertRaises(ValueError, undefined_to_string, "48 50 50 49")
def test_identity(self):
value = "0221"
self.assertEqual(undefined_to_string(string_to_undefined(value)), value)
value = "48 50 50 49"
self.assertEqual(string_to_undefined(undefined_to_string(value)), value)
def _convert_to_python(self, value):
"""
Convert one raw value to its corresponding python type.
:param value: the raw value to be converted
:type value: string
:return: the value converted to its corresponding python type
:raise ExifValueError: if the conversion fails
"""
if self.type == 'Ascii':
# The value may contain a Datetime
for format in self._datetime_formats:
try:
t = time.strptime(value, format)
except ValueError:
continue
else:
return datetime.datetime(*t[:6])
# Or a Date (e.g. Exif.GPSInfo.GPSDateStamp)
for format in self._date_formats:
try:
t = time.strptime(value, format)
except ValueError:
continue
else:
return datetime.date(*t[:3])
# Default to string.
# There is currently no charset conversion.
# TODO: guess the encoding and decode accordingly into unicode
# where relevant.
return value
elif self.type in ('Byte', 'SByte'):
return value
elif self.type == 'Comment':
if value.startswith('charset='):
charset, val = value.split(' ', 1)
charset = charset.split('=')[1].strip('"')
encoding = self._match_encoding(charset)
return val.decode(encoding, 'replace')
else:
# No encoding defined.
try:
return value.decode('utf-8')
except UnicodeError:
return value
elif self.type in ('Short', 'SShort'):
try:
return int(value)
except ValueError:
raise ExifValueError(value, self.type)
elif self.type in ('Long', 'SLong'):
try:
return long(value)
except ValueError:
raise ExifValueError(value, self.type)
elif self.type in ('Rational', 'SRational'):
try:
r = make_fraction(value)
except (ValueError, ZeroDivisionError):
raise ExifValueError(value, self.type)
else:
if self.type == 'Rational' and r.numerator < 0:
raise ExifValueError(value, self.type)
return r
elif self.type == 'Undefined':
# There is currently no charset conversion.
# TODO: guess the encoding and decode accordingly into unicode
# where relevant.
return undefined_to_string(value)
raise ExifValueError(value, self.type)
def test_undefined_to_string(self):
self.assertEqual(undefined_to_string("48 50 50 49"), "0221")
self.assertEqual(undefined_to_string("48 50 50 49 "), "0221")
self.assertRaises(ValueError, undefined_to_string, "")
self.assertRaises(ValueError, undefined_to_string, "foo")
self.assertRaises(ValueError, undefined_to_string, "48 50 50 49")
def _convert_to_python(self, value):
"""
Convert one raw value to its corresponding python type.
:param value: the raw value to be converted
:type value: string
:return: the value converted to its corresponding python type
:raise ExifValueError: if the conversion fails
"""
if self.type == 'Ascii':
# The value may contain a Datetime
for format in self._datetime_formats:
try:
t = time.strptime(value, format)
except ValueError:
continue
else:
return datetime.datetime(*t[:6])
# Or a Date (e.g. Exif.GPSInfo.GPSDateStamp)
for format in self._date_formats:
try:
t = time.strptime(value, format)
except ValueError:
continue
else:
return datetime.date(*t[:3])
# Default to string.
# There is currently no charset conversion.
# TODO: guess the encoding and decode accordingly into unicode
# where relevant.
return value
elif self.type in ('Byte', 'SByte'):
if isinstance(value, bytes):
return value.decode('utf-8')
return value
elif self.type == 'Comment':
if isinstance(value, str):
if value.startswith('charset='):
charset, val = value.split(' ', 1)
return val
return value
if value.startswith(b'charset='):
charset = charset.split('=')[1].strip('"')
encoding = self._match_encoding(charset)
return val.decode(encoding, 'replace')
else:
# No encoding defined.
try:
return value.decode('utf-8')
except UnicodeError:
pass
return value
elif self.type in ('Short', 'SShort'):
try:
return int(value)
except ValueError:
raise ExifValueError(value, self.type)
elif self.type in ('Long', 'SLong'):
try:
return int(value)
except ValueError:
raise ExifValueError(value, self.type)
elif self.type in ('Rational', 'SRational'):
try:
r = make_fraction(value)
except (ValueError, ZeroDivisionError):
raise ExifValueError(value, self.type)
else:
if self.type == 'Rational' and r.numerator < 0:
raise ExifValueError(value, self.type)
return r
elif self.type == 'Undefined':
# There is currently no charset conversion.
# TODO: guess the encoding and decode accordingly into unicode
# where relevant.
return undefined_to_string(value)
raise ExifValueError(value, self.type)
def test_undefined_to_string_invalid(uval):
with pytest.raises(ValueError):
undefined_to_string(uval)
def test_undefined_to_string_oneway(uval, sval):
assert undefined_to_string(uval) == sval
def test_undefined_to_string_invertible(uval, sval):
sxval = undefined_to_string(uval)
uxval = string_to_undefined(sval)
assert sval == sxval
assert uval == uxval