Re: [PATCH v4] log,diff-tree: add --combined-all-names option

>
> Hi Elijah,
>
> On Mon, 4 Feb 2019, Elijah Newren wrote:
>
> > The combined diff format for merges will only list one filename, even if
> > rename or copy detection is active.  For example, with raw format one
> > might see:
> >
> >   ::100644 100644 100644 fabadb8 cc95eb0 4866510 MM   describe.c
> >   ::100755 100755 100755 52b7a2d 6d1ac04 d2ac7d7 RM   bar.sh
> >   ::100644 100644 100644 e07d6c5 9042e82 ee91881 RR   phooey.c
> >
> > This doesn't let us know what the original name of bar.sh was in the
> > first parent, and doesn't let us know what either of the original names
> > of phooey.c were in either of the parents.  In contrast, for non-merge
> > commits, raw format does provide original filenames (and a rename score
> > to boot).  In order to also provide original filenames for merge
> > commits, add a --combined-all-names option (which must be used with
> > either -c or --cc, and is likely only useful with rename or copy
> > detection active) so that we can print tab-separated filenames when
> > renames are involved.  This transforms the above output to:
> >
> >   ::100644 100644 100644 fabadb8 cc95eb0 4866510 MM   desc.c  desc.c  desc.c
> >   ::100755 100755 100755 52b7a2d 6d1ac04 d2ac7d7 RM   foo.sh  bar.sh  bar.sh
> >   ::100644 100644 100644 e07d6c5 9042e82 ee91881 RR   fooey.c fuey.c  phooey.c
> >
> > Further, in patch format, this changes the from/to headers so that
> > instead of just having one "from" header, we get one for each parent.
> > For example, instead of having
> >
> >   --- a/phooey.c
> >   +++ b/phooey.c
> >
> > we would see
> >
> >   --- a/fooey.c
> >   --- a/fuey.c
> >   +++ b/phooey.c
> >
> > Signed-off-by: Elijah Newren <newren@gmail.com>
>
> I do not really see where this needs to have tests with filenames
> containing tabs, but your test does create such files. Which makes it
> break on filesystems that do not allow tabs in file names, such as
> NTFS. I need this to make the test pass again:
>
> -- snip --
> diff --git a/t/t4038-diff-combined.sh b/t/t4038-diff-combined.sh
> index 5bccc323f648..596705985baa 100755
> --- a/t/t4038-diff-combined.sh
> +++ b/t/t4038-diff-combined.sh
> @@ -435,7 +435,7 @@ test_expect_success 'combine diff gets tree sorting right' '
>         test_cmp expect actual
>  '
>
> -test_expect_success 'setup for --combined-with-paths' '
> +test_expect_success FUNNYNAMES 'setup for --combined-with-paths' '
>         git branch side1c &&
>         git branch side2c &&
>         git checkout side1c &&
> @@ -456,7 +456,7 @@ test_expect_success 'setup for --combined-with-paths' '
>         git commit
>  '
>
> -test_expect_success '--combined-all-names and --raw' '
> +test_expect_success FUNNYNAMES '--combined-all-names and --raw' '
>         cat <<-\EOF >expect &&
>         ::100644 100644 100644 f00c965d8307308469e537302baa73048488f162 088bd5d92c2a8e0203ca8e7e4c2a5c692f6ae3f7 333b9c62519f285e1854830ade0fe1ef1d40ee1b RR    "file\twith\ttabs"      "i\tam\ttabbed" "fickle\tnaming"
>         EOF
> @@ -465,13 +465,13 @@ test_expect_success '--combined-all-names and --raw' '
>         test_cmp expect actual
>  '
>
> -test_expect_success '--combined-all-names and --raw -and -z' '
> +test_expect_success FUNNYNAMES '--combined-all-names and --raw -and -z' '
>         printf "0f9645804ebb04cc3eef91f799eb7fb54d70cefb\0::100644 100644 100644 f00c965d8307308469e537302baa73048488f162 088bd5d92c2a8e0203ca8e7e4c2a5c692f6ae3f7 333b9c62519f285e1854830ade0fe1ef1d40ee1b RR\0file\twith\ttabs\0i\tam\ttabbed\0fickle\tnaming\0" >expect &&
>         git diff-tree -c -M --raw --combined-all-names -z HEAD >actual &&
>         test_cmp -a expect actual
>  '
>
> -test_expect_success '--combined-all-names and --cc' '
> +test_expect_success FUNNYNAMES '--combined-all-names and --cc' '
>         cat <<-\EOF >expect &&
>         --- "a/file\twith\ttabs"
>         --- "a/i\tam\ttabbed"
> -- snap --
>
> But maybe you want to get rid of the funny file names? Or test for them in
> a separate, dedicated test case so that we do not have to guard *all* of
> your added tests behind FUNNYNAMES?