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Diffstat (limited to 'pygments/util.py')
| -rw-r--r-- | pygments/util.py | 291 |
1 files changed, 291 insertions, 0 deletions
diff --git a/pygments/util.py b/pygments/util.py new file mode 100644 index 00000000..5dc6981f --- /dev/null +++ b/pygments/util.py @@ -0,0 +1,291 @@ +# -*- coding: utf-8 -*- +""" + pygments.util + ~~~~~~~~~~~~~ + + Utility functions. + + :copyright: Copyright 2006-2014 by the Pygments team, see AUTHORS. + :license: BSD, see LICENSE for details. +""" + +import re +import sys + + +split_path_re = re.compile(r'[/\\ ]') +doctype_lookup_re = re.compile(r'''(?smx) + (<\?.*?\?>)?\s* + <!DOCTYPE\s+( + [a-zA-Z_][a-zA-Z0-9]*\s+ + [a-zA-Z_][a-zA-Z0-9]*\s+ + "[^"]*") + [^>]*> +''') +tag_re = re.compile(r'<(.+?)(\s.*?)?>.*?</.+?>(?uism)') + + +class ClassNotFound(ValueError): + """ + If one of the get_*_by_* functions didn't find a matching class. + """ + + +class OptionError(Exception): + pass + + +def get_choice_opt(options, optname, allowed, default=None, normcase=False): + string = options.get(optname, default) + if normcase: + string = string.lower() + if string not in allowed: + raise OptionError('Value for option %s must be one of %s' % + (optname, ', '.join(map(str, allowed)))) + return string + + +def get_bool_opt(options, optname, default=None): + string = options.get(optname, default) + if isinstance(string, bool): + return string + elif isinstance(string, int): + return bool(string) + elif not isinstance(string, string_types): + raise OptionError('Invalid type %r for option %s; use ' + '1/0, yes/no, true/false, on/off' % ( + string, optname)) + elif string.lower() in ('1', 'yes', 'true', 'on'): + return True + elif string.lower() in ('0', 'no', 'false', 'off'): + return False + else: + raise OptionError('Invalid value %r for option %s; use ' + '1/0, yes/no, true/false, on/off' % ( + string, optname)) + + +def get_int_opt(options, optname, default=None): + string = options.get(optname, default) + try: + return int(string) + except TypeError: + raise OptionError('Invalid type %r for option %s; you ' + 'must give an integer value' % ( + string, optname)) + except ValueError: + raise OptionError('Invalid value %r for option %s; you ' + 'must give an integer value' % ( + string, optname)) + + +def get_list_opt(options, optname, default=None): + val = options.get(optname, default) + if isinstance(val, string_types): + return val.split() + elif isinstance(val, (list, tuple)): + return list(val) + else: + raise OptionError('Invalid type %r for option %s; you ' + 'must give a list value' % ( + val, optname)) + + +def docstring_headline(obj): + if not obj.__doc__: + return '' + res = [] + for line in obj.__doc__.strip().splitlines(): + if line.strip(): + res.append(" " + line.strip()) + else: + break + return ''.join(res).lstrip() + + +def make_analysator(f): + """ + Return a static text analysation function that + returns float values. + """ + def text_analyse(text): + try: + rv = f(text) + except Exception: + return 0.0 + if not rv: + return 0.0 + try: + return min(1.0, max(0.0, float(rv))) + except (ValueError, TypeError): + return 0.0 + text_analyse.__doc__ = f.__doc__ + return staticmethod(text_analyse) + + +def shebang_matches(text, regex): + """ + Check if the given regular expression matches the last part of the + shebang if one exists. + + >>> from pygments.util import shebang_matches + >>> shebang_matches('#!/usr/bin/env python', r'python(2\.\d)?') + True + >>> shebang_matches('#!/usr/bin/python2.4', r'python(2\.\d)?') + True + >>> shebang_matches('#!/usr/bin/python-ruby', r'python(2\.\d)?') + False + >>> shebang_matches('#!/usr/bin/python/ruby', r'python(2\.\d)?') + False + >>> shebang_matches('#!/usr/bin/startsomethingwith python', + ... r'python(2\.\d)?') + True + + It also checks for common windows executable file extensions:: + + >>> shebang_matches('#!C:\\Python2.4\\Python.exe', r'python(2\.\d)?') + True + + Parameters (``'-f'`` or ``'--foo'`` are ignored so ``'perl'`` does + the same as ``'perl -e'``) + + Note that this method automatically searches the whole string (eg: + the regular expression is wrapped in ``'^$'``) + """ + index = text.find('\n') + if index >= 0: + first_line = text[:index].lower() + else: + first_line = text.lower() + if first_line.startswith('#!'): + try: + found = [x for x in split_path_re.split(first_line[2:].strip()) + if x and not x.startswith('-')][-1] + except IndexError: + return False + regex = re.compile('^%s(\.(exe|cmd|bat|bin))?$' % regex, re.IGNORECASE) + if regex.search(found) is not None: + return True + return False + + +def doctype_matches(text, regex): + """ + Check if the doctype matches a regular expression (if present). + Note that this method only checks the first part of a DOCTYPE. + eg: 'html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"' + """ + m = doctype_lookup_re.match(text) + if m is None: + return False + doctype = m.group(2) + return re.compile(regex).match(doctype.strip()) is not None + + +def html_doctype_matches(text): + """ + Check if the file looks like it has a html doctype. + """ + return doctype_matches(text, r'html\s+PUBLIC\s+"-//W3C//DTD X?HTML.*') + + +_looks_like_xml_cache = {} +def looks_like_xml(text): + """ + Check if a doctype exists or if we have some tags. + """ + key = hash(text) + try: + return _looks_like_xml_cache[key] + except KeyError: + m = doctype_lookup_re.match(text) + if m is not None: + return True + rv = tag_re.search(text[:1000]) is not None + _looks_like_xml_cache[key] = rv + return rv + +# Python narrow build compatibility + +def _surrogatepair(c): + # Given a unicode character code + # with length greater than 16 bits, + # return the two 16 bit surrogate pair. + # From example D28 of: + # http://www.unicode.org/book/ch03.pdf + return (0xd7c0 + (c >> 10), (0xdc00 + (c & 0x3ff))) + +def unirange(a, b): + """ + Returns a regular expression string to match the given non-BMP range. + """ + if b < a: + raise ValueError("Bad character range") + if a < 0x10000 or b < 0x10000: + raise ValueError("unirange is only defined for non-BMP ranges") + + if sys.maxunicode > 0xffff: + # wide build + return u'[%s-%s]' % (unichr(a), unichr(b)) + else: + # narrow build stores surrogates, and the 're' module handles them + # (incorrectly) as characters. Since there is still ordering among + # these characters, expand the range to one that it understands. Some + # background in http://bugs.python.org/issue3665 and + # http://bugs.python.org/issue12749 + # + # Additionally, the lower constants are using unichr rather than + # literals because jython [which uses the wide path] can't load this + # file if they are literals. + ah, al = _surrogatepair(a) + bh, bl = _surrogatepair(b) + if ah == bh: + return u'(?:%s[%s-%s])' % (unichr(ah), unichr(al), unichr(bl)) + else: + buf = [] + buf.append(u'%s[%s-%s]' % + (unichr(ah), unichr(al), + ah == bh and unichr(bl) or unichr(0xdfff))) + if ah - bh > 1: + buf.append(u'[%s-%s][%s-%s]' % + unichr(ah+1), unichr(bh-1), unichr(0xdc00), unichr(0xdfff)) + if ah != bh: + buf.append(u'%s[%s-%s]' % + (unichr(bh), unichr(0xdc00), unichr(bl))) + + return u'(?:' + u'|'.join(buf) + u')' + +# Python 2/3 compatibility + +if sys.version_info < (3, 0): + unichr = unichr + xrange = xrange + string_types = (str, unicode) + text_type = unicode + u_prefix = 'u' + iteritems = dict.iteritems + itervalues = dict.itervalues + import StringIO, cStringIO + # unfortunately, io.StringIO in Python 2 doesn't accept str at all + StringIO = StringIO.StringIO + BytesIO = cStringIO.StringIO +else: + unichr = chr + xrange = range + string_types = (str,) + text_type = str + u_prefix = '' + iteritems = dict.items + itervalues = dict.values + from io import StringIO, BytesIO + +def add_metaclass(metaclass): + """Class decorator for creating a class with a metaclass.""" + def wrapper(cls): + orig_vars = cls.__dict__.copy() + orig_vars.pop('__dict__', None) + orig_vars.pop('__weakref__', None) + for slots_var in orig_vars.get('__slots__', ()): + orig_vars.pop(slots_var) + return metaclass(cls.__name__, cls.__bases__, orig_vars) + return wrapper |