Re: Cloned repository has file changes -> bug?

I’m not git expert but, from a user point of view, the following would make sense. When adding a file, git could check whether a different file is already in the repository with the same name (case-insensitive check). Then simply report that this may be a mistake and request to use ‘git add -f’ to force the ‘add’. Perhaps this coincides with what was suggested in earlier replies. From my point of view the check should be enabled by default, but it could be optional too. 

Filip

Op 6 feb. 2018, om 15:14 heeft Jeff King [off-list ref] het volgende geschreven:

On Tue, Feb 06, 2018 at 02:24:25PM +0100, Ævar Arnfjörð Bjarmason wrote:

quoted

3) Such hooks slow down pushes, especially on big repos, you can
   optimize things a bit (e.g. only look in the same directories), but
   pathologically you end up needing to compare the cross-product of
   changed files v.s. all existing files for each changed file.

I think you could just complain about any tree that contains entries
that have duplicate entries after normalization. I.e.:

 git rev-list --objects $new --not $old |
 awk '{print $1}' |
 git cat-file --batch-check='%(objecttype) %(objectname)' |
 awk '/^tree/ {print $2}'|
 while read tree; do
	dups=$(git ls-tree $tree | cut -f 2- | tr A-Z a-z | sort | uniq -d)
	test -z "$dups" || echo "$tree has duplicates: $dups"
 done

That gives reasonable algorithmic complexity, but of course the shell
implementation is horrific. One could imagine that this could be
implemented as part of fsck_tree(), though, which is already reading
through all the entries (unfortunately it requires auxiliary storage
linear with the size of a given tree object, but that's not too bad).

But it would probably need:

 1. To be enabled as an optional fsck warning, possibly even defaulting
    to "ignore".

 2. That "tr" could be any arbitrary transformation. Case-folding is
    the obvious one, but in theory you could match the normalization
    behavior of certain popular filesystems.

I'm not entirely convinced it's worth all of this effort, but I think it
would be _possible_ at least.

-Peff