Re: [PATCH 2/2] repository: allow repository format upgrade with extensions
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Jul 16, 2020, 07:01 UTC
- Message-ID
- <xmqqh7u8hrka.fsf@gitster.c.googlers.com>
- In-Reply-To
- <20200716062818.GC3242764@google.com>
Jonathan Nieder <jrnieder@gmail.com> writes:
Show 13 quoted lines
> Now that we officially permit repository extensions in repository > format v0, permit upgrading a repository with extensions from v0 to v1 > as well. > > For example, this means a repository where the user has set > "extensions.preciousObjects" can use "git fetch --filter=blob:none > origin" to upgrade the repository to use v1 and the partial clone > extension. > > To avoid mistakes, continue to forbid repository format upgrades in v0 > repositories with an unrecognized extension. This way, a v0 user > using a misspelled extension field gets a chance to correct the > mistake before updating to the less forgiving v1 format.
This needs to be managed carefully. When the next extension is added to the codebase, that extension may be "known" to Git, but I do not think it is a good idea to honor it in v0 repository, or allow upgrading v0 repository to v1 with such an extension that weren't "known" to Git. For example, a topic in flight adds objectformat extension and I do not think it should be honored in v0 repository.
Having said that, the approach is OK for now at the tip of tonight's master, but the point is "known" vs "unknown" must be fixed right with some means. E.g. tell people to throw the "new" extensions to the list of "unknown extensions" in check_repo_format() when they add new ones, or something.
Thanks.
Show 29 quoted lines
> + if (!repo_fmt.version && repo_fmt.unknown_extensions.nr)
> + return error("cannot upgrade repository format: "
> + "unknown extension %s",
> + repo_fmt.unknown_extensions.items[0].string);
>
> strbuf_addf(&repo_version, "%d", target_version);
> git_config_set("core.repositoryformatversion", repo_version.buf);
> diff --git a/t/t0410-partial-clone.sh b/t/t0410-partial-clone.sh
> index 51d1eba6050..6aa0f313bdd 100755
> --- a/t/t0410-partial-clone.sh
> +++ b/t/t0410-partial-clone.sh
> @@ -42,7 +42,7 @@ test_expect_success 'convert shallow clone to partial clone' '
> test_cmp_config -C client 1 core.repositoryformatversion
> '
>
> -test_expect_success 'converting to partial clone fails with noop extension' '
> +test_expect_success 'convert to partial clone with noop extension' '
> rm -fr server client &&
> test_create_repo server &&
> test_commit -C server my_commit 1 &&
> @@ -50,7 +50,7 @@ test_expect_success 'converting to partial clone fails with noop extension' '
> git clone --depth=1 "file://$(pwd)/server" client &&
> test_cmp_config -C client 0 core.repositoryformatversion &&
> git -C client config extensions.noop true &&
> - test_must_fail git -C client fetch --unshallow --filter="blob:none"
> + git -C client fetch --unshallow --filter="blob:none"
> '
>
> test_expect_success 'converting to partial clone fails with unrecognized extension' '