1 files changed, 102 insertions, 0 deletions
diff --git a/pygments/util.py b/pygments/util.py
index 4a427fb8..8ad994c6 100644
--- a/pygments/util.py
+++ b/pygments/util.py
@@ -9,6 +9,19 @@
     :copyright: 2006 by Georg Brandl.
     :license: GNU LGPL, see LICENSE for more details.
 """
+import re
+
+
+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.*?)?>.*?</\1>(?uism)')
 
 
 class OptionError(Exception):
@@ -49,3 +62,92 @@ def get_list_opt(options, optname, default=None):
         raise OptionError('Invalid value %r for option %s; you '
                           'must give a list value' %
                           val, optname)
+
+
+def make_analysator(f):
+    """
+    Return a static text analysation function that
+    returns float values.
+    """
+    def text_analyse(text):
+        rv = f(text)
+        if not rv:
+            return 0.0
+        return min(1.0, max(0.0, float(rv)))
+    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 ``'^$'``)
+    """
+    if '\n' in text:
+        first_line = text[:text.index('\n')].lower()
+    else:
+        first_line = text.lower()
+    if first_line.startswith('#!'):
+        try:
+            found = [x for x in split_path_re.split(first_line[2:].strip())
+                     if x and not x.startswith('-')][-1]
+        except IndexError:
+            return False
+        regex = re.compile('^%s(\.(exe|cmd|bat|bin))?$' % 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.*')
+
+
+def looks_like_xml(text):
+    """
+    Check if a doctype exists or if we have some tags
+    """
+    m = doctype_lookup_re.match(text)
+    if m is not None:
+        return True
+    return tag_re.search(text) is not None