Re: [PATCH v2 2/2] revision: allow --ancestry-path to take an argument

From: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date: Aug 18, 2022, 15:50 UTC
Message-ID: <220818.86ilmp8rzn.gmgdl@evledraar.gmail.com>
In-Reply-To: <ee4a7a7f-d646-6357-233a-1fefde5607bf@github.com>

On Thu, Aug 18 2022, Derrick Stolee wrote:

Show 15 quoted lines

> On 8/18/2022 2:17 AM, Elijah Newren via GitGitGadget wrote:
>> +test_expect_success 'rev-list --ancestry-path=F D..M' '
>> +	test_write_lines E F J L M >expect &&
>> +	git rev-list --ancestry-path=F --format=%s D..M |
>> +	sed -e "/^commit /d" |
>> +	sort >actual &&
>> +	test_cmp expect actual
>> +'
>
> These tests follow the patterns from other tests in this file, but
> it also has bad patterns. Specifically, the 'git rev-list' command
> is fed directly into a pipe. I include a patch below that applies
> directly on this one to rewrite these tests. If you want, you could
> rebase to have that test refactor happen before you add your new
> --ancestry-path=<X> option tests.

Thanks, I was going to comment on the same, but your solution is much better (I was just going to suggest using intermediate files).

Show 10 quoted lines

> [...]
> -test_expect_success 'rev-list --ancestry-path D..M -- M.t' '
> -	echo M >expect &&
> -	git rev-list --ancestry-path --format=%s D..M -- M.t |
> -	sed -e "/^commit /d" >actual &&
> -	test_cmp expect actual
> -'
> +test_ancestry () {
> +	args=$1
> +	expected=$2

Maybe add &&-chaining here (we do it in some cases, but I'm not sure when such assignments would ever fail).

Show 5 quoted lines

> +	test_expect_success "rev-list $args" "
> +		test_write_lines $expected >expect &&
> +		git rev-list --format=%s $args >raw &&
> +
> +		if test -n \"$expected\"

Aren't you making things harder for yourself here than required by using ""-quoting for the body of the test.

We eval it into existence, so you can use ''-quotes, and then you don't need to escape e.g. the "" quotes here for expected, no?

> +		then
> +			sed -e \"/^commit /d\" raw | sort >actual &&

nit for debuggability (and not correctness), maybe using intermediate files here would be nicer? And then perhaps call them "actual" and "actual.sorted".

> +			test_cmp expect actual || return 1

No need for a "return 1" here when we're not in a loop. It's redundant, and makes the -x output on failure confusing ("why didn't I fail on the test_cmp, but on this stray return?...").

...

> +		else
> +			test_must_be_empty raw

...which would also allow you to extract much of this if/else at the cost of not using test_must_be_empty, i.e. just make the "expected" empty unless "$expected" is provided. Just a thought/nit, we could also leave this as-is :)

Also does the "compare rev" part of this want test_cmp_rev instead?