Re: [PATCH 1/3] t6423: test directory renames causing rename-to-self

>
> On 6/26/2021 1:05 PM, Elijah Newren via GitGitGadget wrote:
> > From: Elijah Newren <newren@gmail.com>
> >
> > Directory rename detection can cause transitive renames, e.g. if the two
> > different sides of history each do one half of:
> >     A/file -> B/file
> >     B/     -> C/
> > then directory rename detection transitively renames to give us C/file.
> > Since the default for merge.directoryRenames is conflict, this results
> > in an error message saying it is unclear whether the file should be
> > placed at B/file or C/file.
> >
> > What if C/ is A/, though?
>
> This case seems interesting, but somehow missing from the test cases
> below. Each of those cases include renaming up or down the directory
> hierarchy instead of doing a sideways rename.
>
> > +# Testcase 12i, Directory rename causes rename-to-self
> > +#   Commit O: source/{subdir/foo, bar, baz_1}
> > +#   Commit A: source/{foo, bar, baz_1}
> > +#   Commit B: source/{subdir/{foo, bar}, baz_2}
> > +#   Expected: source/{foo, bar, baz_2}, with conflicts on
> > +#                source/bar vs. source/subdir/bar
>
> This test goes deeper.
>
> > +# Testcase 12j, Directory rename to root causes rename-to-self
> > +#   Commit O: {subdir/foo, bar, baz_1}
> > +#   Commit A: {foo, bar, baz_1}
> > +#   Commit B: {subdir/{foo, bar}, baz_2}
> > +#   Expected: {foo, bar, baz_2}, with conflicts on bar vs. subdir/bar
>
> This test goes higher.
>
> Does the problematic case not hit when going out to the side, such
> as "with conflicts on subdir/bar vs otherdir/bar"?
>
> If so, then _maybe_ the commit message could indicate this is an
> omission on purpose. If not, then maybe a third test should be
> added?