Breaking python2.4 compatibility for bzr-2.4

[Martin (gzlist)]

On 20/04/2011, John Arbash Meinel <john at arbash-meinel.com> wrote:
>
> This has been discussed a bit in the past, and Martin and I have chatted
> about it a bit recently on IRC. I've personally reached my threshold,
> and would like to break compatibility with python 2.4 for our next
> release (bzr 2.4).

I'd much prefer if Bazaar 2.4 supported Python 2.4 still.

> 2) try/finally in generators. This helps a lot to make cleanup in a
>    generator much clearer.
>
> 3) try/except/finally, also nice to have. Not critical, but definitely
>    nice to have.
>
> 4) with: statements. Along the same lines of "make your cleanup
>    clearer".

I'm not convinced any of these are really compelling. The sugar
doesn't hurt, but 'with' is used to obfuscate as much as it is to
clarify, and sloppy cleanup is a problem with code, not the language.

> 5) If we go all the way to python2.6 compatibility we can start looking
>    at doing things to support Python 3.
>    (This is my recommendation, since RHEL6 has python2.6, and I don't
>    think anything else is strictly blocked for python2.5)

Is there anyone who actually wants to work on this though? I note the
last release of testtools was broken on Python 3 again and wasn't
noticed. There's a lot to do in the codebase as it stands over bytes
vs. unicode before getting on to worrying about whether print need
parentheses.

> 6) PQM is now running the test suite directly with python2.6. We plan
>    on having Babune run python2.4 compatibility tests, but that is
>    going to be a longer turn-around time from finding out you did
>    something not-2.4 (5) compatible and fixing it.

I'm happy to continue running tests and fixing things when they break
as I've needed to in the past anyway.

Martin