Re: [PATCH v2 1/3] object tests: add test for unexpected objects in tags

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

Ævar Arnfjörð Bjarmason  <avarab@gmail.com> writes:

> +test_expect_success !SANITIZE_LEAK 'setup unexpected non-tag tag' '
> +	test_when_finished "git tag -d tag-commit tag-tag" &&
> +
> +	git tag -a -m"my tagged commit" tag-commit $commit &&
> +	tag_commit=$(git rev-parse tag-commit) &&
> +	git tag -a -m"my tagged tag" tag-tag tag-commit &&
> +	tag_tag=$(git rev-parse tag-tag) &&
> +
> +	git cat-file tag tag-tag >good-tag-tag &&
> +	git cat-file tag tag-commit >good-commit-tag &&
> +
> +	sed -e "s/$tag_commit/$commit/" <good-tag-tag >broken-tag-tag-commit &&
> +	sed -e "s/$tag_commit/$tree/" <good-tag-tag >broken-tag-tag-tree &&
> +	sed -e "s/$tag_commit/$blob/" <good-tag-tag >broken-tag-tag-blob &&
> +
> +	sed -e "s/$commit/$tag_commit/" <good-commit-tag >broken-commit-tag-tag &&
> +	sed -e "s/$commit/$tree/" <good-commit-tag >broken-commit-tag-tree &&
> +	sed -e "s/$commit/$blob/" <good-commit-tag >broken-commit-tag-blob &&
> +
> +	tag_tag_commit=$(git hash-object -w -t tag broken-tag-tag-commit) &&
> +	tag_tag_tree=$(git hash-object -w -t tag broken-tag-tag-tree) &&
> +	tag_tag_blob=$(git hash-object -w -t tag broken-tag-tag-blob) &&

If the second block of 3 sed commands to prepare data for tags that
incorrectly claim to point at a commit are moved a bit, i.e. make
"sed's && hash-object's && update-ref's" as a logical group, the
above would become slightly easier to read, but in any case the
set-up step looks quite repetitive and boring to read ;-)

There is no strong reason to use broken-tag-* temporary files,
though.  Each of them is used exactly once, but you can just
pipe the output from "sed" to "git hash-object --stdin" without
losing any exit status, e.g.

	tag_tag_commit=$(sed -e '...' good-commit-tag |
			git hash-object -w -t tag --stdin)

> +	git update-ref refs/tags/tag_tag_commit $tag_tag_commit &&
> +	git update-ref refs/tags/tag_tag_tree $tag_tag_tree &&
> +	git update-ref refs/tags/tag_tag_blob $tag_tag_blob &&
> +
> +	commit_tag_tag=$(git hash-object -w -t tag broken-commit-tag-tag) &&
> +	commit_tag_tree=$(git hash-object -w -t tag broken-commit-tag-tree) &&
> +	commit_tag_blob=$(git hash-object -w -t tag broken-commit-tag-blob) &&
> +
> +	git update-ref refs/tags/commit_tag_tag $commit_tag_tag &&
> +	git update-ref refs/tags/commit_tag_tree $commit_tag_tree &&
> +	git update-ref refs/tags/commit_tag_blob $commit_tag_blob
> +'
> +
> +test_expect_failure !SANITIZE_LEAK 'traverse unexpected incorrectly typed tag (to commit & tag)' '
> +	test_must_fail git rev-list --objects $tag_tag_commit 2>err &&

Does this have to be "rev-list --objects" or would something like
"cat-file -t $tag_tag_commit^0" do?

Especially because "rev-list --objects" is a rather heavy-weight
command that does a lot of checking, I am wondering if it is
sensible to rely on the assumption that the errors expected below
will stay to be the only errors we get before the command exits
(hence a wish to replace it with a more narrowly focused comamnd).

> +	cat >expect <<-EOF &&
> +	error: object $commit is a commit, not a tag
> +	fatal: bad object $commit
> +	EOF
> +	test_cmp expect err &&



> +test_expect_failure !SANITIZE_LEAK 'traverse unexpected objects with for-each-ref' '
> +	cat >expect <<-EOF &&
> +	error: bad tag pointer to $tree in $tag_tag_tree
> +	fatal: parse_object_buffer failed on $tag_tag_tree for refs/tags/tag_tag_tree
> +	EOF

This depends on the fact that among the broken ones tag_tag_tree
sorts the earliest (and the command stops after barfing on a single
bad object), doesn't it?  I wonder if it makes the test more robust
by feeding refs/tags/tag_tag_tree from the command line to limit the
tips the command needs to inspect.

> +>fsck-object-isa

Move it inside the setup as the first command in case "git fsck"
succeeds?

> +test_expect_success 'setup: unexpected objects with fsck' '
> +	test_must_fail git fsck 2>err &&
> +	sed -n -e "/^error: object .* is a .*, not a .*$/ {
> +		s/^error: object \([0-9a-f]*\) is a \([a-z]*\), not a [a-z]*$/\\1 \\2/;
> +		p;
> +	}" <err >fsck-object-isa
> +'