import re from django.conf import settings from django.utils.encoding import force_unicode from django.utils.functional import allow_lazy from django.utils.translation import ugettext_lazy from htmlentitydefs import name2codepoint # Capitalizes the first letter of a string. capfirst = lambda x: x and force_unicode(x)[0].upper() + force_unicode(x)[1:] capfirst = allow_lazy(capfirst, unicode) def wrap(text, width): """ A word-wrap function that preserves existing line breaks and most spaces in the text. Expects that existing line breaks are posix newlines. """ text = force_unicode(text) def _generator(): it = iter(text.split(' ')) word = it.next() yield word pos = len(word) - word.rfind('\n') - 1 for word in it: if "\n" in word: lines = word.split('\n') else: lines = (word,) pos += len(lines[0]) + 1 if pos > width: yield '\n' pos = len(lines[-1]) else: yield ' ' if len(lines) > 1: pos = len(lines[-1]) yield word return u''.join(_generator()) wrap = allow_lazy(wrap, unicode) def truncate_words(s, num): "Truncates a string after a certain number of words." s = force_unicode(s) length = int(num) words = s.split() if len(words) > length: words = words[:length] if not words[-1].endswith('...'): words.append('...') return u' '.join(words) truncate_words = allow_lazy(truncate_words, unicode) def truncate_html_words(s, num): """ Truncates html to a certain number of words (not counting tags and comments). Closes opened tags if they were correctly closed in the given html. """ s = force_unicode(s) length = int(num) if length <= 0: return u'' html4_singlets = ('br', 'col', 'link', 'base', 'img', 'param', 'area', 'hr', 'input') # Set up regular expressions re_words = re.compile(r'&.*?;|<.*?>|(\w[\w-]*)', re.U) re_tag = re.compile(r'<(/)?([^ ]+?)(?: (/)| .*?)?>') # Count non-HTML words and keep note of open tags pos = 0 ellipsis_pos = 0 words = 0 open_tags = [] while words <= length: m = re_words.search(s, pos) if not m: # Checked through whole string break pos = m.end(0) if m.group(1): # It's an actual non-HTML word words += 1 if words == length: ellipsis_pos = pos continue # Check for tag tag = re_tag.match(m.group(0)) if not tag or ellipsis_pos: # Don't worry about non tags or tags after our truncate point continue closing_tag, tagname, self_closing = tag.groups() tagname = tagname.lower() # Element names are always case-insensitive if self_closing or tagname in html4_singlets: pass elif closing_tag: # Check for match in open tags list try: i = open_tags.index(tagname) except ValueError: pass else: # SGML: An end tag closes, back to the matching start tag, all unclosed intervening start tags with omitted end tags open_tags = open_tags[i+1:] else: # Add it to the start of the open tags list open_tags.insert(0, tagname) if words <= length: # Don't try to close tags if we don't need to truncate return s out = s[:ellipsis_pos] + ' ...' # Close any tags still open for tag in open_tags: out += '' % tag # Return string return out truncate_html_words = allow_lazy(truncate_html_words, unicode) def get_valid_filename(s): """ Returns the given string converted to a string that can be used for a clean filename. Specifically, leading and trailing spaces are removed; other spaces are converted to underscores; and anything that is not a unicode alphanumeric, dash, underscore, or dot, is removed. >>> get_valid_filename("john's portrait in 2004.jpg") u'johns_portrait_in_2004.jpg' """ s = force_unicode(s).strip().replace(' ', '_') return re.sub(r'(?u)[^-\w.]', '', s) get_valid_filename = allow_lazy(get_valid_filename, unicode) def get_text_list(list_, last_word=ugettext_lazy(u'or')): """ >>> get_text_list(['a', 'b', 'c', 'd']) u'a, b, c or d' >>> get_text_list(['a', 'b', 'c'], 'and') u'a, b and c' >>> get_text_list(['a', 'b'], 'and') u'a and b' >>> get_text_list(['a']) u'a' >>> get_text_list([]) u'' """ if len(list_) == 0: return u'' if len(list_) == 1: return force_unicode(list_[0]) return u'%s %s %s' % (', '.join([force_unicode(i) for i in list_][:-1]), force_unicode(last_word), force_unicode(list_[-1])) get_text_list = allow_lazy(get_text_list, unicode) def normalize_newlines(text): return force_unicode(re.sub(r'\r\n|\r|\n', '\n', text)) normalize_newlines = allow_lazy(normalize_newlines, unicode) def recapitalize(text): "Recapitalizes text, placing caps after end-of-sentence punctuation." text = force_unicode(text).lower() capsRE = re.compile(r'(?:^|(?<=[\.\?\!] ))([a-z])') text = capsRE.sub(lambda x: x.group(1).upper(), text) return text recapitalize = allow_lazy(recapitalize) def phone2numeric(phone): "Converts a phone number with letters into its numeric equivalent." letters = re.compile(r'[A-PR-Y]', re.I) char2number = lambda m: {'a': '2', 'c': '2', 'b': '2', 'e': '3', 'd': '3', 'g': '4', 'f': '3', 'i': '4', 'h': '4', 'k': '5', 'j': '5', 'm': '6', 'l': '5', 'o': '6', 'n': '6', 'p': '7', 's': '7', 'r': '7', 'u': '8', 't': '8', 'w': '9', 'v': '8', 'y': '9', 'x': '9'}.get(m.group(0).lower()) return letters.sub(char2number, phone) phone2numeric = allow_lazy(phone2numeric) # From http://www.xhaus.com/alan/python/httpcomp.html#gzip # Used with permission. def compress_string(s): import cStringIO, gzip zbuf = cStringIO.StringIO() zfile = gzip.GzipFile(mode='wb', compresslevel=6, fileobj=zbuf) zfile.write(s) zfile.close() return zbuf.getvalue() ustring_re = re.compile(u"([\u0080-\uffff])") def javascript_quote(s, quote_double_quotes=False): def fix(match): return r"\u%04x" % ord(match.group(1)) if type(s) == str: s = s.decode('utf-8') elif type(s) != unicode: raise TypeError, s s = s.replace('\\', '\\\\') s = s.replace('\r', '\\r') s = s.replace('\n', '\\n') s = s.replace('\t', '\\t') s = s.replace("'", "\\'") if quote_double_quotes: s = s.replace('"', '"') return str(ustring_re.sub(fix, s)) javascript_quote = allow_lazy(javascript_quote, unicode) # Expression to match some_token and some_token="with spaces" (and similarly # for single-quoted strings). smart_split_re = re.compile(r""" ([^\s"]*"(?:[^"\\]*(?:\\.[^"\\]*)*)"\S*| [^\s']*'(?:[^'\\]*(?:\\.[^'\\]*)*)'\S*| \S+)""", re.VERBOSE) def smart_split(text): r""" Generator that splits a string by spaces, leaving quoted phrases together. Supports both single and double quotes, and supports escaping quotes with backslashes. In the output, strings will keep their initial and trailing quote marks and escaped quotes will remain escaped (the results can then be further processed with unescape_string_literal()). >>> list(smart_split(r'This is "a person\'s" test.')) [u'This', u'is', u'"a person\\\'s"', u'test.'] >>> list(smart_split(r"Another 'person\'s' test.")) [u'Another', u"'person\\'s'", u'test.'] >>> list(smart_split(r'A "\"funky\" style" test.')) [u'A', u'"\\"funky\\" style"', u'test.'] """ text = force_unicode(text) for bit in smart_split_re.finditer(text): yield bit.group(0) smart_split = allow_lazy(smart_split, unicode) def _replace_entity(match): text = match.group(1) if text[0] == u'#': text = text[1:] try: if text[0] in u'xX': c = int(text[1:], 16) else: c = int(text) return unichr(c) except ValueError: return match.group(0) else: try: return unichr(name2codepoint[text]) except (ValueError, KeyError): return match.group(0) _entity_re = re.compile(r"&(#?[xX]?(?:[0-9a-fA-F]+|\w{1,8}));") def unescape_entities(text): return _entity_re.sub(_replace_entity, text) unescape_entities = allow_lazy(unescape_entities, unicode) def unescape_string_literal(s): r""" Convert quoted string literals to unquoted strings with escaped quotes and backslashes unquoted:: >>> unescape_string_literal('"abc"') 'abc' >>> unescape_string_literal("'abc'") 'abc' >>> unescape_string_literal('"a \"bc\""') 'a "bc"' >>> unescape_string_literal("'\'ab\' c'") "'ab' c" """ if s[0] not in "\"'" or s[-1] != s[0]: raise ValueError("Not a string literal: %r" % s) quote = s[0] return s[1:-1].replace(r'\%s' % quote, quote).replace(r'\\', '\\') unescape_string_literal = allow_lazy(unescape_string_literal)