Re: [PATCH v2 00/14] Sparse-checkout: modify 'git add', 'git rm', and 'git add' behavior

[Derrick Stolee <stolee@gmail.com>]

On 10/18/2021 5:28 PM, Sean Christopherson wrote:
> On Sun, Sep 12, 2021, Derrick Stolee via GitGitGadget wrote:
>> This series is based on ds/mergies-with-sparse-index.
>>
>> As requested, this series looks to update the behavior of git add, git rm,
>> and git mv when they attempt to modify paths outside of the sparse-checkout
>> cone. In particular, this care is expanded to not just cache entries with
>> the SKIP_WORKTREE bit, but also paths that do not match the sparse-checkout
>> definition.
> 
> I suspect something in this series broke 'git add' and friends with "odd" sparse
> definitions (I haven't actually bisected).  git 2.33.0 rejects attempts to add
> files with the below sparse-checkout and modified files.  There appears to be a
> discrepancy in the query vs. checkout logic as the rejected files are checked out
> in the working tree, e.g. git sees that the local file was deleted, yet will not
> stage the deletion.

Are you using v2.33.0? This change is not in that version.

However, mt/add-rm-in-sparse-checkout [1] was introduced in v2.33.0 and
introduced these advice suggestions.

[1] https://github.com/git/git/compare/a5828ae6b52137b913b978e16cd2334482eb4c1f...d5f4b8260f623d6fdef36d5eaa8a0c2350390472

The series you are commenting on goes even farther in restricting adds to
be within the sparse-checkout definitions, even for unstaged files or files
that removed the skip-worktree bit due to a merge conflict. It also creates
an override '--sparse' option that allows you to ignore these protections.

> There's also arguably a flaw in the "advise" trigger.  AFAICT, the help message
> is displayed if and only if the entire path is excluded from the working tree.
> In my perfect world, git would complain and advise if there are unstaged changes
> for tracked files covered by the specified path.
>> Note, my sparse-checkout is very much the result of trial and error to get the
> exact files I care about.  It's entirely possible I'm doing something weird, but
> at the same time git itself is obviously confused.
> 
> Thanks!
> 
> $ cat .git/info/sparse-checkout
> !arch/*
> !tools/arch/*
> !virt/kvm/arm/*
> /*
> arch/.gitignore
> arch/Kconfig
> arch/x86
> tools/arch/x86
> tools/include/uapi/linux/kvm.h
> !Documentation
> !drivers

Have you tried using 'arch/x86/' and 'tools/arch/x86/' to specify
that these are directories? Just a thought.

> $ git read-tree -mu HEAD
> 
> $ rm arch/x86/kvm/x86.c
> 
> $ git commit -a
...
> 	deleted:    arch/x86/kvm/x86.c

This is certainly odd. Worth more investigation that I don't have
time for at this moment.

Thanks,
-Stolee