Hi guys. I found that GZipWriteStream throws an error when closing it twice. Example:

| aStream zipStream |
aStream := ByteArray new writeStream binary.
zipStream := GZipWriteStream on: aStream.
zipStream close.
zipStream close.

All the streams I know do not throw an error in that case. And moreoever, it gets things complicated when using #on:do:. For example:

�� FileStream
�� forceNewFileNamed: testFileName
�� do: [ :stream |
�� GZipWriteStream
�� on: stream binary
�� do: [ :gzipStream |
�� FLSerializer newDefault serialize: anObject on: gzipStream ] ].

In thise case, FLSerializer closes the stream at the end. No matter whether Fuel should do that or not, the thing is that in this I have the mentioned problem.

So...my question is, is this a bug?� if it is, do you have a better idea that changing #close to this:

ZipWriteStream >> close
�� literals isNil ifTrue: [
�� "#initialize sets this instVar to a specific value. #release puts it in nil, and #release is called from #flushBlock: which is called from #close:. Therefore, if it is nil, it means the stream has already been closed. If we try to close it twice, #flushBlock will throw an error because its instance variables are with nil"
�� ^ self]
�� self deflateBlock.
�� self flushBlock: true.
�� encoder close.

--
Mariano
http://marianopeck.wordpress.com