[BuildStream] Proposed removal of `workspace reset --soft`

[Darius Makovsky <darius makovsky codethink co uk>]

After looking at the `--soft` option of `workspace reset` I'm still
unclear on the exact use-case now that workspaces are being loaded via
the workspace source plugin. It would simplify support for workspaces if
this option were simply removed. As I understand it, originally this was
intended as a way for a developer to execute the configure commands on
an open workspace without affecting the contents. However, in most cases
someone would want to do this due to some change in the workspace which
would result in a different key for that source. In that case the
workspace would have to be re-cached anyway.

Related to this is a question about the continued need for the
`prepared` attribute of workspaces: This is really only used to prevent
executing configure-commands in a sandbox and again ideally we'd hope
that in any case where we don't skip this, the key of the workspace
source has changed. It seems that it would be correct in those cases to
execute the configure-commands. In my opinion, Buildstream can't
accurately decide whether the result of executing configure-commands
will be different in any case other than the source remaining unchanged.
If the source has not changed then I don't think those jobs should be
run at all.

Will someone please point out to me why these features have been
retained? It would simplify things if we could just remove them. I
understand there is some concern about duplication but I think in this
case we might be asking Buildstream to decide more than can be known and
things which should be deferred to the underlying build tool.

-- 
Best Regards,
Darius


For Codethink's privacy-policy please see
https://www.codethink.co.uk/privacy.html