SickGear/lib/hachoir/field/fake_array.py

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import itertools
from hachoir.field import MissingField
class FakeArray:
"""
Simulate an array for GenericFieldSet.array(): fielset.array("item")[0] is
equivalent to fielset.array("item[0]").
It's possible to iterate over the items using::
for element in fieldset.array("item"):
...
And to get array size using len(fieldset.array("item")).
"""
def __init__(self, fieldset, name):
pos = name.rfind("/")
if pos != -1:
self.fieldset = fieldset[name[:pos]]
self.name = name[pos + 1:]
else:
self.fieldset = fieldset
self.name = name
self._format = "%s[%%u]" % self.name
self._cache = {}
self._known_size = False
self._max_index = -1
def __bool__(self):
"Is the array empty or not?"
if self._cache:
return True
else:
return (0 in self)
def __len__(self):
"Number of fields in the array"
total = self._max_index + 1
if not self._known_size:
for index in itertools.count(total):
try:
self[index]
total += 1
except MissingField:
break
return total
def __contains__(self, index):
try:
self[index]
return True
except MissingField:
return False
def __getitem__(self, index):
"""
Get a field of the array. Returns a field, or raise MissingField
exception if the field doesn't exist.
"""
try:
value = self._cache[index]
except KeyError:
try:
value = self.fieldset[self._format % index]
except MissingField:
self._known_size = True
raise
self._cache[index] = value
self._max_index = max(index, self._max_index)
return value
def __iter__(self):
"""
Iterate in the fields in their index order: field[0], field[1], ...
"""
for index in itertools.count(0):
try:
yield self[index]
except MissingField:
break