157 lines
4.9 KiB
Python
157 lines
4.9 KiB
Python
# -*- coding: utf-8 -*-
|
|
#
|
|
# Copyright (c), 2016-2019, SISSA (International School for Advanced Studies).
|
|
# All rights reserved.
|
|
# This file is distributed under the terms of the MIT License.
|
|
# See the file 'LICENSE' in the root directory of the present
|
|
# distribution, or http://opensource.org/licenses/MIT.
|
|
#
|
|
# @author Davide Brunato <brunato@sissa.it>
|
|
#
|
|
"""
|
|
This module contains various helper functions and classes.
|
|
"""
|
|
from decimal import Decimal
|
|
|
|
from .compat import string_base_type
|
|
from .exceptions import XMLSchemaValueError
|
|
from .qnames import XSD_ANNOTATION
|
|
from .xpath import ElementPathMixin
|
|
|
|
XSD_FINAL_ATTRIBUTE_VALUES = {'restriction', 'extension', 'list', 'union'}
|
|
|
|
|
|
def is_etree_element(elem):
|
|
"""More safer test for matching ElementTree elements."""
|
|
return hasattr(elem, 'tag') and hasattr(elem, 'attrib') and not isinstance(elem, ElementPathMixin)
|
|
|
|
|
|
def get_xsd_annotation(elem):
|
|
"""
|
|
Returns the annotation of an XSD component.
|
|
|
|
:param elem: ElementTree's node
|
|
:return: The first child element containing an XSD annotation, `None` if \
|
|
the XSD information item doesn't have an annotation.
|
|
"""
|
|
try:
|
|
return elem[0] if elem[0].tag == XSD_ANNOTATION else None
|
|
except (TypeError, IndexError):
|
|
return
|
|
|
|
|
|
def get_xsd_derivation_attribute(elem, attribute, values=None):
|
|
"""
|
|
Get a derivation attribute (maybe 'block', 'blockDefault', 'final' or 'finalDefault')
|
|
checking the items with the values arguments. Returns a string.
|
|
|
|
:param elem: the Element instance.
|
|
:param attribute: the attribute name.
|
|
:param values: sequence of admitted values when the attribute value is not '#all'.
|
|
:return: a string.
|
|
"""
|
|
value = elem.get(attribute)
|
|
if value is None:
|
|
return ''
|
|
|
|
if values is None:
|
|
values = XSD_FINAL_ATTRIBUTE_VALUES
|
|
|
|
items = value.split()
|
|
if len(items) == 1 and items[0] == '#all':
|
|
return ' '.join(values)
|
|
elif not all(s in values for s in items):
|
|
raise XMLSchemaValueError("wrong value %r for attribute %r." % (value, attribute))
|
|
return value
|
|
|
|
|
|
def get_xsd_form_attribute(elem, attribute):
|
|
"""
|
|
Get an XSD form attribute, checking the value. If the attribute is missing returns `None`
|
|
|
|
:param elem: the Element instance.
|
|
:param attribute: the attribute name (maybe 'form', or 'elementFormDefault' or 'attributeFormDefault').
|
|
:return: a string.
|
|
"""
|
|
value = elem.get(attribute)
|
|
if value is None:
|
|
return
|
|
elif value not in ('qualified', 'unqualified'):
|
|
raise XMLSchemaValueError(
|
|
"wrong value %r for attribute %r, it must be 'qualified' or 'unqualified'." % (value, attribute)
|
|
)
|
|
return value
|
|
|
|
|
|
def count_digits(number):
|
|
"""
|
|
Counts the digits of a number.
|
|
|
|
:param number: an int or a float or a Decimal or a string representing a number.
|
|
:return: a couple with the number of digits of the integer part and \
|
|
the number of digits of the decimal part.
|
|
"""
|
|
if isinstance(number, string_base_type):
|
|
number = str(Decimal(number)).lstrip('-+')
|
|
else:
|
|
number = str(number).lstrip('-+')
|
|
|
|
if 'E' in number:
|
|
significand, _, exponent = number.partition('E')
|
|
elif 'e' in number:
|
|
significand, _, exponent = number.partition('e')
|
|
elif '.' not in number:
|
|
return len(number.lstrip('0')), 0
|
|
else:
|
|
integer_part, _, decimal_part = number.partition('.')
|
|
return len(integer_part.lstrip('0')), len(decimal_part.rstrip('0'))
|
|
|
|
significand = significand.strip('0')
|
|
exponent = int(exponent)
|
|
|
|
num_digits = len(significand) - 1 if '.' in significand else len(significand)
|
|
if exponent > 0:
|
|
return num_digits + exponent, 0
|
|
else:
|
|
return 0, num_digits - exponent - 1
|
|
|
|
|
|
def strictly_equal(obj1, obj2):
|
|
"""Checks if the objects are equal and are of the same type."""
|
|
return obj1 == obj2 and type(obj1) is type(obj2)
|
|
|
|
|
|
class ParticleCounter(object):
|
|
"""
|
|
An helper class for counting total min/max occurrences of XSD particles.
|
|
"""
|
|
def __init__(self):
|
|
self.min_occurs = self.max_occurs = 0
|
|
|
|
def __repr__(self):
|
|
return '%s(%r, %r)' % (self.__class__.__name__, self.min_occurs, self.max_occurs)
|
|
|
|
def __add__(self, other):
|
|
self.min_occurs += other.min_occurs
|
|
if self.max_occurs is not None:
|
|
if other.max_occurs is None:
|
|
self.max_occurs = None
|
|
else:
|
|
self.max_occurs += other.max_occurs
|
|
return self
|
|
|
|
def __mul__(self, other):
|
|
self.min_occurs *= other.min_occurs
|
|
if self.max_occurs is None:
|
|
if other.max_occurs == 0:
|
|
self.max_occurs = 0
|
|
elif other.max_occurs is None:
|
|
if self.max_occurs != 0:
|
|
self.max_occurs = None
|
|
else:
|
|
self.max_occurs *= other.max_occurs
|
|
return self
|
|
|
|
def reset(self):
|
|
self.min_occurs = self.max_occurs = 0
|