Two merges from the mimelib project:
_split_header(): Split on folding whitespace if the attempt to split
on semi-colons failed.
_split_header(): Patch by Matthew Cowles for fixing SF bug # 471918,
Generator splitting long headers.
diff --git a/Lib/email/Generator.py b/Lib/email/Generator.py
index c31dc80..12b9fdf 100644
--- a/Lib/email/Generator.py
+++ b/Lib/email/Generator.py
@@ -15,10 +15,12 @@
import Message
import Errors
+EMPTYSTRING = ''
SEMISPACE = '; '
BAR = '|'
UNDERSCORE = '_'
NL = '\n'
+NLTAB = '\n\t'
SEMINLTAB = ';\n\t'
SPACE8 = ' ' * 8
@@ -171,18 +173,47 @@
# Short lines can remain unchanged
if len(line.replace('\t', SPACE8)) <= maxheaderlen:
rtn.append(line)
+ SEMINLTAB.join(rtn)
else:
+ oldlen = len(text)
# Try to break the line on semicolons, but if that doesn't
- # work, then just leave it alone.
+ # work, try to split on folding whitespace.
while len(text) > maxheaderlen:
i = text.rfind(';', 0, maxheaderlen)
if i < 0:
- rtn.append(text)
break
rtn.append(text[:i])
text = text[i+1:].lstrip()
- rtn.append(text)
- return SEMINLTAB.join(rtn)
+ if len(text) <> oldlen:
+ # Splitting on semis worked
+ rtn.append(text)
+ return SEMINLTAB.join(rtn)
+ # Splitting on semis didn't help, so try to split on
+ # whitespace.
+ parts = re.split(r'(\s+)', text)
+ # Watch out though for "Header: longnonsplittableline"
+ if parts[0].endswith(':') and len(parts) == 3:
+ return text
+ first = parts.pop(0)
+ sublines = [first]
+ acc = len(first)
+ while parts:
+ len0 = len(parts[0])
+ len1 = len(parts[1])
+ if acc + len0 + len1 < maxheaderlen:
+ sublines.append(parts.pop(0))
+ sublines.append(parts.pop(0))
+ acc += len0 + len1
+ else:
+ # Split it here, but don't forget to ignore the
+ # next whitespace-only part
+ rtn.append(EMPTYSTRING.join(sublines))
+ del parts[0]
+ first = parts.pop(0)
+ sublines = [first]
+ acc = len(first)
+ rtn.append(EMPTYSTRING.join(sublines))
+ return NLTAB.join(rtn)
#
# Handlers for writing types and subtypes