Issue #14874: Restore charmap decoding speed to pre-PEP 393 levels.
Patch by Serhiy Storchaka.
diff --git a/Tools/unicode/gencodec.py b/Tools/unicode/gencodec.py
index 7e7d6d0..f5a1af3 100644
--- a/Tools/unicode/gencodec.py
+++ b/Tools/unicode/gencodec.py
@@ -102,7 +102,7 @@
comment = ''
else:
comment = comment[1:].strip()
- if enc < 256:
+ if not isinstance(enc, tuple) and enc < 256:
if enc in unmapped:
unmapped.remove(enc)
if enc == uni:
@@ -202,11 +202,10 @@
# Analyze map and create table dict
mappings = sorted(map.items())
table = {}
- maxkey = 0
+ maxkey = 255
if 'IDENTITY' in map:
for key in range(256):
table[key] = (key, '')
- maxkey = 255
del map['IDENTITY']
for mapkey, mapvalue in mappings:
mapcomment = ''
@@ -224,6 +223,7 @@
return None
# Create table code
+ maxchar = 0
for key in range(maxkey + 1):
if key not in table:
mapvalue = MISSING_CODE
@@ -238,6 +238,7 @@
return None
else:
mapchar = chr(mapvalue)
+ maxchar = max(maxchar, ord(mapchar))
if mapcomment and comments:
append(' %a \t# %s -> %s' % (mapchar,
hexrepr(key, key_precision),
@@ -245,6 +246,8 @@
else:
append(' %a' % mapchar)
+ if maxchar < 256:
+ append(' %a \t## Widen to UCS2 for optimization' % UNI_UNDEFINED)
append(')')
return l