[Python-bugs-list] mimetools.{encode,decode} should handle trivial encodings (PR#273)

[skip@mojam.com]

Full_Name: Skip Montanaro
Version: 1.5.2+/1.6a1
OS: Linux
Submission from: beluga.mojam.com (199.249.165.173)


mimetools.{encode,decode} handle a number of different content transer
encodings, but don't handle trivial encodings like 7bit and 8bit.  It seems
to me that it would simplify callers' code if these functions handled these
common cases.  For example, a loop over a MultiFile object code be coded as

    file = multifile.MultiFile(sys.stdin)
    file.push(boundary)
    while file.next():
        submessage = mimetools.Message(file)
        try:
            data = mimetools.decode(file.read(), submessage.getencoding())
        except ValueError:
            print "unknown encoding:", submessage.getencoding()
            continue
        process_data(data)
     file.pop()

with the expectation that hitting "except ValueError" would actually be
exceptional.  Because 7bit and 8bit encodings are not currently handled, all
calling code has to handle the relatively common (and trivial) cases.

Here's a patch that just does a noop for encoding and decoding 7bit/8bit
data.

*** /tmp/mimetools.py.~1.16~qKA6Tr	Tue Apr  4 13:16:41 2000
--- /tmp/mimetools.pyqKAHex	Tue Apr  4 13:16:41 2000
***************
*** 140,145 ****
--- 140,147 ----
  	if encoding in ('uuencode', 'x-uuencode', 'uue', 'x-uue'):
  		import uu
  		return uu.decode(input, output)
+ 	if encoding in ('7bit', '8bit'):
+ 		output.write(input.read())
  	if decodetab.has_key(encoding):
  		pipethrough(input, decodetab[encoding], output)
  	else:
***************
*** 157,162 ****
--- 159,166 ----
  	if encoding in ('uuencode', 'x-uuencode', 'uue', 'x-uue'):
  		import uu
  		return uu.encode(input, output)
+ 	if encoding in ('7bit', '8bit'):
+ 		output.write(input.read())
  	if encodetab.has_key(encoding):
  		pipethrough(input, encodetab[encoding], output)
  	else:



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Skip Montanaro
skip@mojam.com