Re: [PATCH v8 7/7] list-objects-filter: implement filter tree:0

[Junio C Hamano <gitster@pobox.com>]

Matthew DeVore <matvore@google.com> writes:

> diff --git a/list-objects-filter-options.c b/list-objects-filter-options.c
> index c0e2bd6a0..14f251de4 100644
> --- a/list-objects-filter-options.c
> +++ b/list-objects-filter-options.c
> @@ -50,6 +50,20 @@ static int gently_parse_list_objects_filter(
>  			return 0;
>  		}
>  
> +	} else if (skip_prefix(arg, "tree:", &v0)) {
> +		unsigned long depth;
> +		if (!git_parse_ulong(v0, &depth) || depth != 0) {
> +			if (errbuf) {
> +				strbuf_init(errbuf, 0);
> +				strbuf_addstr(
> +					errbuf,
> +					_("only 'tree:0' is supported"));

This is not a new issue with this patch, but I think strbuf_init()
at the location of filling done like this is a bad idea.  If the
caller gave you an errbuf that is pre-filled with something, we'd
leak memory and lose information.  It only makes sense to _init() if
the caller gave us an uninitialized garbage (or a strbuf that has
just been initialized and is empty).  

The existing callers seem to do STRBUF_INIT before passing it to
this function, so we probably should not do strbuf_init() here (and
other two places in this function) and simply add to it.

> diff --git a/t/t5616-partial-clone.sh b/t/t5616-partial-clone.sh
> index bbbe7537d..8eeb85fbc 100755
> --- a/t/t5616-partial-clone.sh
> +++ b/t/t5616-partial-clone.sh
> @@ -154,6 +154,44 @@ test_expect_success 'partial clone with transfer.fsckobjects=1 uses index-pack -
>  	grep "git index-pack.*--fsck-objects" trace
>  '
>  
> +test_expect_success 'use fsck before and after manually fetching a missing subtree' '
> +	# push new commit so server has a subtree
> +	mkdir src/dir &&
> +	echo "in dir" >src/dir/file.txt &&
> +	git -C src add dir/file.txt &&
> +	git -C src commit -m "file in dir" &&
> +	git -C src push -u srv master &&
> +	SUBTREE=$(git -C src rev-parse HEAD:dir) &&
> +
> +	rm -rf dst &&
> +	git clone --no-checkout --filter=tree:0 "file://$(pwd)/srv.bare" dst &&
> +	git -C dst fsck &&
> +
> +	# Make sure we only have commits, and all trees and blobs are missing.
> +	git -C dst rev-list master --missing=allow-any --objects >fetched_objects &&
> +	awk -f print_1.awk fetched_objects \
> +		| xargs -n1 git -C dst cat-file -t >fetched_types &&

Break line after pipe "|", not before, and lose the backslash.  You
do not need to over-indent the command on the downstream of the
pipe, i.e.

	awk ... |
	xargs -n1 git -C ... &&

Same comment applies elsewhere in this patch, not limited to this file.

> +	sort fetched_types -u >unique_types.observed &&

Make it a habit not to add dashed options after real arguments, i.e.

	sort -u fetched_types

> +	echo commit >unique_types.expected &&
> +	test_cmp unique_types.observed unique_types.expected &&

Always compare "expect" with "actual", not in the reverse order, i.e.

	test_cmp expect actual

not

	test_cmp actual expect

This is important because test_cmp reports failures by showing you
an output of "diff expect actual" and from "sh t5616-part*.sh -v"
you can see what additional/excess things were produced by the test
over what is expected, prefixed with "+", and what your code failed
to produce are shown prefixed with "-".

Thanks.