Re: [PATCH 0/9] No more adding submodule ODB as alternate

> This series is on jt/add-submodule-odb-clean-up.
>
> After this series, the entire test suite runs without ever adding a
> submodule ODB as an alternate (checked by running with
> GIT_TEST_FATAL_REGISTER_SUBMODULE_ODB=1). The code to lazily add
> submodule ODBs as alternates still remains (with a trace message printed
> if it happens) just in case there is a rare interaction that the test
> suite doesn't cover.
>
> This is part of my effort to support partial clone in submodules, but
> the results here are also beneficial for non-partial-clone submodule
> users in that access to submodule objects are now quicker (because Git
> no longer needs to linearly search through alternates when accessing
> these objects). It also improves code health in that it is clearer at
> the call site when a submodule object is being accessed.