Re: [PATCH 2/8] tests: add checking that combine-diff emits only correct paths

> where "correct paths" stands for paths that are different to all
> parents.
>
> Up until now, we were testing combined diff only on one file, or on
> several files which were all different (t4038-diff-combined.sh).
>
> As recent thinko in "simplify intersect_paths() further" showed, and
> also, since we are going to rework code for finding paths different to
> all parents, lets write at least basic tests.

>
> Signed-off-by: Kirill Smelkov <kirr@mns.spb.ru>
> ---
>  t/t4057-diff-combined-paths.sh | 106 +++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 106 insertions(+)
>  create mode 100755 t/t4057-diff-combined-paths.sh
>
> diff --git a/t/t4057-diff-combined-paths.sh b/t/t4057-diff-combined-paths.sh
> new file mode 100755
> index 0000000..e6e457d
> --- /dev/null
> +++ b/t/t4057-diff-combined-paths.sh
> @@ -0,0 +1,106 @@
> +#!/bin/sh
> +
> +test_description='combined diff show only paths that are different to all parents'
> +
> +. ./test-lib.sh
> +
> +# verify that diffc.expect matches output of
> +# `git diff -c --name-only HEAD HEAD^ HEAD^2`
> +diffc_verify() {

> +	git diff -c --name-only HEAD HEAD^ HEAD^2 >diffc.actual &&
> +	test_cmp diffc.expect diffc.actual
> +}
> +
> +test_expect_success 'trivial merge - combine-diff empty' '
> +	for i in `test_seq 1 9`