Source code for pygments.lexers

# -*- coding: utf-8 -*-
"""
    pygments.lexers
    ~~~~~~~~~~~~~~~

    Pygments lexers.

    :copyright: Copyright 2006-2013 by the Pygments team, see AUTHORS.
    :license: BSD, see LICENSE for details.
"""

import sys
import types
import fnmatch
from os.path import basename

from pygments.lexers._mapping import LEXERS
from pygments.plugin import find_plugin_lexers
from pygments.util import ClassNotFound, bytes


__all__ = ['get_lexer_by_name', 'get_lexer_for_filename', 'find_lexer_class',
           'guess_lexer'] + LEXERS.keys()

_lexer_cache = {}


def _load_lexers(module_name):
    """
    Load a lexer (and all others in the module too).
    """
    mod = __import__(module_name, None, None, ['__all__'])
    for lexer_name in mod.__all__:
        cls = getattr(mod, lexer_name)
        _lexer_cache[cls.name] = cls


def get_all_lexers():
    """
    Return a generator of tuples in the form ``(name, aliases,
    filenames, mimetypes)`` of all know lexers.
    """
    for item in LEXERS.itervalues():
        yield item[1:]
    for lexer in find_plugin_lexers():
        yield lexer.name, lexer.aliases, lexer.filenames, lexer.mimetypes


[docs]def find_lexer_class(name): """ Lookup a lexer class by name. Return None if not found. """ if name in _lexer_cache: return _lexer_cache[name] # lookup builtin lexers for module_name, lname, aliases, _, _ in LEXERS.itervalues(): if name == lname: _load_lexers(module_name) return _lexer_cache[name] # continue with lexers from setuptools entrypoints for cls in find_plugin_lexers(): if cls.name == name: return cls
[docs]def get_lexer_by_name(_alias, **options): """ Get a lexer by an alias. """ # lookup builtin lexers for module_name, name, aliases, _, _ in LEXERS.itervalues(): if _alias in aliases: if name not in _lexer_cache: _load_lexers(module_name) return _lexer_cache[name](**options) # continue with lexers from setuptools entrypoints for cls in find_plugin_lexers(): if _alias in cls.aliases: return cls(**options) raise ClassNotFound('no lexer for alias %r found' % _alias)
[docs]def get_lexer_for_filename(_fn, code=None, **options): """ Get a lexer for a filename. If multiple lexers match the filename pattern, use ``analyze_text()`` to figure out which one is more appropriate. """ matches = [] fn = basename(_fn) for modname, name, _, filenames, _ in LEXERS.itervalues(): for filename in filenames: if fnmatch.fnmatch(fn, filename): if name not in _lexer_cache: _load_lexers(modname) matches.append((_lexer_cache[name], filename)) for cls in find_plugin_lexers(): for filename in cls.filenames: if fnmatch.fnmatch(fn, filename): matches.append((cls, filename)) if sys.version_info > (3,) and isinstance(code, bytes): # decode it, since all analyse_text functions expect unicode code = code.decode('latin1') def get_rating(info): cls, filename = info # explicit patterns get a bonus bonus = '*' not in filename and 0.5 or 0 # The class _always_ defines analyse_text because it's included in # the Lexer class. The default implementation returns None which # gets turned into 0.0. Run scripts/detect_missing_analyse_text.py # to find lexers which need it overridden. if code: return cls.analyse_text(code) + bonus return cls.priority + bonus if matches: matches.sort(key=get_rating) #print "Possible lexers, after sort:", matches return matches[-1][0](**options) raise ClassNotFound('no lexer for filename %r found' % _fn)
def get_lexer_for_mimetype(_mime, **options): """ Get a lexer for a mimetype. """ for modname, name, _, _, mimetypes in LEXERS.itervalues(): if _mime in mimetypes: if name not in _lexer_cache: _load_lexers(modname) return _lexer_cache[name](**options) for cls in find_plugin_lexers(): if _mime in cls.mimetypes: return cls(**options) raise ClassNotFound('no lexer for mimetype %r found' % _mime) def _iter_lexerclasses(): """ Return an iterator over all lexer classes. """ for key in sorted(LEXERS): module_name, name = LEXERS[key][:2] if name not in _lexer_cache: _load_lexers(module_name) yield _lexer_cache[name] for lexer in find_plugin_lexers(): yield lexer def guess_lexer_for_filename(_fn, _text, **options): """ Lookup all lexers that handle those filenames primary (``filenames``) or secondary (``alias_filenames``). Then run a text analysis for those lexers and choose the best result. usage:: >>> from pygments.lexers import guess_lexer_for_filename >>> guess_lexer_for_filename('hello.html', '<%= @foo %>') <pygments.lexers.templates.RhtmlLexer object at 0xb7d2f32c> >>> guess_lexer_for_filename('hello.html', '<h1>{{ title|e }}</h1>') <pygments.lexers.templates.HtmlDjangoLexer object at 0xb7d2f2ac> >>> guess_lexer_for_filename('style.css', 'a { color: <?= $link ?> }') <pygments.lexers.templates.CssPhpLexer object at 0xb7ba518c> """ fn = basename(_fn) primary = None matching_lexers = set() for lexer in _iter_lexerclasses(): for filename in lexer.filenames: if fnmatch.fnmatch(fn, filename): matching_lexers.add(lexer) primary = lexer for filename in lexer.alias_filenames: if fnmatch.fnmatch(fn, filename): matching_lexers.add(lexer) if not matching_lexers: raise ClassNotFound('no lexer for filename %r found' % fn) if len(matching_lexers) == 1: return matching_lexers.pop()(**options) result = [] for lexer in matching_lexers: rv = lexer.analyse_text(_text) if rv == 1.0: return lexer(**options) result.append((rv, lexer)) result.sort() if not result[-1][0] and primary is not None: return primary(**options) return result[-1][1](**options)
[docs]def guess_lexer(_text, **options): """ Guess a lexer by strong distinctions in the text (eg, shebang). """ best_lexer = [0.0, None] for lexer in _iter_lexerclasses(): rv = lexer.analyse_text(_text) if rv == 1.0: return lexer(**options) if rv > best_lexer[0]: best_lexer[:] = (rv, lexer) if not best_lexer[0] or best_lexer[1] is None: raise ClassNotFound('no lexer matching the text found') return best_lexer[1](**options)
class _automodule(types.ModuleType): """Automatically import lexers.""" def __getattr__(self, name): info = LEXERS.get(name) if info: _load_lexers(info[0]) cls = _lexer_cache[info[1]] setattr(self, name, cls) return cls raise AttributeError(name) oldmod = sys.modules['pygments.lexers'] newmod = _automodule('pygments.lexers') newmod.__dict__.update(oldmod.__dict__) sys.modules['pygments.lexers'] = newmod del newmod.newmod, newmod.oldmod, newmod.sys, newmod.types

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