def validate_nodes(sentence1, sentence2):
"""
Compares tag and text nodes between two sentences
:return is_valid (Boolean), reason (String)
"""
# Extract tags position
sent1_tags = get_tags_positions(sentence1)
sent2_tags = get_tags_positions(sentence2)
# Extract text and tags position
sent1_pos, _ = _split_text_tags(sentence1, sent1_tags)
sent2_pos, _ = _split_text_tags(sentence2, sent2_tags)
# Get list with separate node strings
sent1_nodes = [sentence1[i[0]:i[1]] for i in sent1_pos if i[0] != i[1]]
sent2_nodes = [sentence2[i[0]:i[1]] for i in sent2_pos if i[0] != i[1]]
if len(sent1_nodes) != len(sent2_nodes):
return False, u'Number of nodes don\'t match'
for i, (s1, s2) in enumerate(itertools.izip(sent1_nodes, sent2_nodes)):
s1_type = u'tag' if patt.match(s1) else u'text'
s2_type = u'tag' if patt.match(s2) else u'text'
if s1_type != s2_type:
return False, (u'Nodes on index {} have different types. '
u'Sentence 1: {}, '
u'Sentence 2: {}').format(i, s1_type, s2_type)
return True, None
