#18020: improve html.escape speed by an order of magnitude. Patch by Matt Bryant.

Lib/html/__init__.py

@@ -2,11 +2,6 @@
 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):
@@ -16,6 +11,10 @@ def escape(s, quote=True):
     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

Misc/ACKS

@@ -172,6 +172,7 @@ Dave Brueck
 Francisco Martín Brugué
 Ian Bruntlett
 Floris Bruynooghe
+Matt Bryant
 Stan Bubrouski
 Erik de Bueger
 Jan-Hein Bührman

Misc/NEWS

@@ -142,6 +142,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #18020: improve html.escape speed by an order of magnitude.
+  Patch by Matt Bryant.
+
 - Issue #18347: ElementTree's html serializer now preserves the case of
   closing tags.