Re: [PATCH 0/3] Fix stash apply in sparse checkouts (and a submodule test)

> Heavier usage of sparse-checkouts at $DAYJOB is commencing. And an issue
> with git stash apply was found.
>
> git stash's implementation as a pipeline of forked commands presents some
> problems, especially when implemented atop of three commands that all behave
> differently in the presence of sparse checkouts. Add a testcase
> demonstrating some issues with git stash apply in a repository with a
> different set of sparse-checkout patterns at apply vs create time, clean up
> the relevant section of git stash code, and incidentally fix a submodule
> testcase unrelated to sparse checkouts. Provide some detailed commit
> messages explaining the issues along the way.
>
> NOTE: I found a couple minor issues with other commands in sparse checkouts
> while debugging this issue, but I don't yet have fixes for them and I can
> submit them separately.