Re: [PATCH v3 3/8] update-index: add --force-full-index option for expand/collapse test

Victoria Dye [off-list ref] writes:

I tried coming up with a user-facing name that wasn't too focused on the
internal implementation, but it ends up being misleading. The intention was
to have this be a variation of `git update-index` that uses the default
setting for `command_requires_full_index` but then proceeds to read and
write the index as `update-index` normally would. Something like
`--use-default-index-sparsity` might have been more accurate?

The option name in the reviewed patch does imply "we force expanding
to full" and not "use the default", so it probably needs renaming,
if we want the "use the default" semantics.  But is that useful in
the context of the test you are using it in place of "reset" or "mv"?
Even if the default is somehow flipped to use sparse always, wouldn't
the particular test want the index expanded?  I dunno.

In the test's use-case, `active_cache_changed` ends up set to
`CACHE_TREE_CHANGED`, which forces writing the index. It is still
effectively a no-op, but it serves the needs of the test.

Ah, cache-tree is updated, then it's OK.

As to test-tool vs end-user-accessible-command, I do not have a
strong opinion, but use your imagination and ask Derrick or somebody
else for their imagination to see if such a "force expand" feature
may be something the end-users might need an access to in order to
dig themselves out of a hole (in which case, it may be better to
make it end-user-accessible) or not (in which case, test-tool is
more appropriate).

Thanks.