[issue41210] LZMADecompressor.decompress(FORMAT_RAW) truncate output when input is paticular LZMA+BCJ data

[Hiroshi Miura]

Hiroshi Miura <miurahr at linux.com> added the comment:

>    Compression filters:
>            FILTER_LZMA1 (for use with FORMAT_ALONE)
>            FILTER_LZMA2 (for use with FORMAT_XZ and FORMAT_RAW)

I look into past discussion  BPO-6715 when lzma module proposed.
https://bugs.python.org/issue6715

There is an only comment about FORMAT_ALONE and LZMA1 here 
https://bugs.python.org/issue6715#msg92174

> .lzma is actually not a format. It is just the raw output of the LZMA1
> coder. XZ instead is a container format for the LZMA2 coder, which
probably means LZMA+some metadata.

It said FORMAT_ALONE decode .lzma archive which use LZMA1 as coder and FORMAT_XZ decode .xz archive which use LZMA2 as coder.
There are no discussion about FORMAT_RAW.

This indicate an opposite relation between two things.
FORMAT_ALONE should use with LZMA1.
FORMAT_XZ should use with LZMA2. 

FORMAT_RAW actually no limitation against LZMA1/2.

Here is another discussion about lzma_raw_encoder and LZMA1.
A xz/liblzma maintainer Lasse suggest lzma_raw_encoder is usable for LZMA1.
https://sourceforge.net/p/lzmautils/discussion/708858/thread/cd04b6ace0/#6050


I think we need fix the document.

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<https://bugs.python.org/issue41210>
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