Re: [PATCH 1/3] test-tool: add pack-deltas helper

Derrick Stolee [off-list ref] writes:

This makes sense as a feature, except that we need to write the number
of objects present in a packfile in its header. If we wanted to avoid
the argument, then we'd need to load the data into a list before
starting to write the packfile. By taking the count in advance, the
implementation is simpler.

Perhaps, but in the production code we already seek back and update
the header after writing a packfile with fixup_pack_header_footer(),
so which shoulnd't be too much work conceptually.  You earlier said
something about faster development cycles; not having to figure out
how to seek back and fix the header does help faster development of
this helper ;-).

quoted

One thing it lets
us do to have this as a separate number is to create an invalid pack
stream where the header gives a wrong number, and as a test tool,
that may trump the convenience of not having to give the number
explicitly.

But also, this allows generating bad packfiles which is a bonus.
A very good point. 

If this were an end-user facing program, we would most likely let it
count but let the count be overridden by the command line argument.

But until then, as I said, I am fine to just declare that it is just
a test helper ;-)

Thanks.