Subject: Re: [PATCH v2 3/4] t4054: test diff --no-index with stdin

From: Junio C Hamano <[email-masked]>
Date: Wed, 05 Jul 2023 14:22:51 -0700

Phillip Wood <[email-masked]> writes:

> +	cat >expect <<-EOF &&
> +	diff --git a/- b/a/1
> +	index $ZERO_OID..$(git hash-object --stdin <a/1) 100644
> +	--- a/-
> +	+++ b/a/1
> +	@@ -1 +1 @@
> +	-x
> +	+1
> +	EOF
> +
> +	test_write_lines x | test_expect_code 1 \
> +		git -c core.abbrev=no diff --no-index -- - a/1 >actual &&

Or "git diff --no-index --full-index -- - a/1", which looks somewhat
odd but may be correct and a bit shorter ;-)

Not a suggestion to use --full-index instead of core.abbrev; both
are equally valid.

> +	test_cmp expect actual &&
> +
> +	test_write_lines 1 | git diff --no-index -- a/1 - >actual &&
> +	test_must_be_empty actual
> +'

Good.

>  test_expect_success 'diff --no-index refuses to diff stdin and a directory' '
>  	test_must_fail git diff --no-index -- - a </dev/null 2>err &&
>  	grep "fatal: cannot compare stdin to a directory" err