Replace the html.escape() function from Py3.3 with the one from Py3.4

The newer function happens to be a polymorphic bytes/unicode interface on Py2.
This should fix issue #108:

    TypeError: character mapping must return integer, None or unicode

Author: edschofield

src/future/moves/html/__init__.py

@@ -1,31 +1,31 @@
-from __future__ import absolute_import, unicode_literals
+from __future__ import absolute_import
 from future.utils import PY3
 __future_module__ = True
 
 if PY3:
     from html import *
 else:
-
     # cgi.escape isn't good enough for the single Py3.3 html test to pass.
-    # Define it inline here instead. From the Py3.3 stdlib
+    # Define it inline here instead. From the Py3.4 stdlib. Note that the
+    # html.escape() function from the Py3.3 stdlib is not suitable for use on
+    # Py2.x.
     """
     General functions for HTML manipulation.
     """
 
-
-    _escape_map = {ord('&'): '&amp;', ord('<'): '&lt;', ord('>'): '&gt;'}
-    _escape_map_full = {ord('&'): '&amp;', ord('<'): '&lt;', ord('>'): '&gt;',
-                        ord('"'): '&quot;', ord('\''): '&#x27;'}
-
-    # NB: this is a candidate for a bytes/string polymorphic interface
-
     def escape(s, quote=True):
         """
         Replace special characters "&", "<" and ">" to HTML-safe sequences.
         If the optional flag quote is true (the default), the quotation mark
         characters, both double quote (") and single quote (') characters are also
         translated.
         """
+        s = s.replace("&", "&amp;") # Must be done first!
+        s = s.replace("<", "&lt;")
+        s = s.replace(">", "&gt;")
         if quote:
-            return s.translate(_escape_map_full)
-        return s.translate(_escape_map)
+            s = s.replace('"', "&quot;")
+            s = s.replace('\'', "&#x27;")
+        return s
+
+    __all__ = ['escape']

src/html/__init__.py

@@ -4,28 +4,5 @@
 
 if sys.version_info[0] == 3:
     raise ImportError('Cannot import module from python-future source folder')
-
 else:
-    # cgi.escape isn't good enough for the single Py3.3 html test to pass.
-    # Define it inline here instead. From the Py3.3 stdlib
-    """
-    General functions for HTML manipulation.
-    """
-
-
-    _escape_map = {ord('&'): '&amp;', ord('<'): '&lt;', ord('>'): '&gt;'}
-    _escape_map_full = {ord('&'): '&amp;', ord('<'): '&lt;', ord('>'): '&gt;',
-                        ord('"'): '&quot;', ord('\''): '&#x27;'}
-
-    # NB: this is a candidate for a bytes/string polymorphic interface
-
-    def escape(s, quote=True):
-        """
-        Replace special characters "&", "<" and ">" to HTML-safe sequences.
-        If the optional flag quote is true (the default), the quotation mark
-        characters, both double quote (") and single quote (') characters are also
-        translated.
-        """
-        if quote:
-            return s.translate(_escape_map_full)
-        return s.translate(_escape_map)
+    from future.moves.html import *