[2/3] t5509: initialized `pushee` as bare repository

Commit Message

Linus Arver via GitGitGadget Feb. 13, 2020, 6:59 p.m. UTC

From: Hariom Verma <[e-mail]>

`receive.denyCurrentBranch` currently has a bug where it allows pushing
into the current branch of a non-bare repository as long as it does not
have any commits. This would cause t5509 to fail once that bug is fixed
because it pushes into an unborn current branch.

In t5509, no operations are performed inside `pushee`, as it is only a
target for `git push` and `git ls-remote` calls. Therefore it does not
need to have a worktree. So, it is safe to change `pushee` to a bare
repository.

Helped-by: Johannes Schindelin <[e-mail]>
Signed-off-by: Hariom Verma <[e-mail]>
---
 t/t5509-fetch-push-namespaces.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Junio C Hamano Feb. 13, 2020, 8:14 p.m. UTC | #1

"Hariom Verma via GitGitGadget" <[e-mail]> writes:

> From: Hariom Verma <[e-mail]>
>
> `receive.denyCurrentBranch` currently has a bug where it allows pushing
> into the current branch of a non-bare repository as long as it does not
> have any commits.

Can patch 3/3 be split into two, so that the fix would protect an
already populated branch that is checked out anywhere (not in the
primary worktree--which is the bug you are fixing) from getting
updated but still allow an unborn branch to be updated, and then
have patch 4/3 that forbids an update to even an unborn branch
"checked out" in any working tree?  This update to the test can then
become part of patch 4/3.

Thanks.

Junio C Hamano Feb. 13, 2020, 8:34 p.m. UTC | #2

Junio C Hamano <[e-mail]> writes:

> "Hariom Verma via GitGitGadget" <[e-mail]> writes:
>
>> From: Hariom Verma <[e-mail]>
>>
>> `receive.denyCurrentBranch` currently has a bug where it allows pushing
>> into the current branch of a non-bare repository as long as it does not
>> have any commits.
>
> Can patch 3/3 be split into two, so that the fix would protect an
> already populated branch that is checked out anywhere (not in the
> primary worktree--which is the bug you are fixing) from getting
> updated but still allow an unborn branch to be updated, and then
> have patch 4/3 that forbids an update to even an unborn branch
> "checked out" in any working tree?  This update to the test can then
> become part of patch 4/3.

Oh, another thing.  The patch 4/3 that starts forbidding a push into
a checked out unborn branch should also have a test that makes sure
that such an attempt fails.  IOW, making the test repository used in
the test you changed to a bare one, to allow existing test to still
test what it wants to test, like you did in this patch is OK, but we
would want to have a new test that prepares a repository with the
primary and the secondary worktrees, check out an unborn branch in
each of the worktrees, and make sure receive.denyCurrentBranch would
prevent "git push" to update these branches.

Thanks.

Johannes Schindelin Feb. 14, 2020, 11:59 a.m. UTC | #3

Hi Junio,

On Thu, 13 Feb 2020, Junio C Hamano wrote:

> "Hariom Verma via GitGitGadget" <[e-mail]> writes:
>
> > From: Hariom Verma <[e-mail]>
> >
> > `receive.denyCurrentBranch` currently has a bug where it allows pushing
> > into the current branch of a non-bare repository as long as it does not
> > have any commits.
>
> Can patch 3/3 be split into two,

I actually don't think so. The `refs_resolve_unsafe()` function simply
requires a tip commit, so it is the wrong function to call in this
context. And the fix for it is to use a more appropriate function, which
3/3 already does (although for an unrelated reason).

In other words, a fix for one bug would be a fix for the other, and
(probably) vice versa.

> so that the fix would protect an already populated branch that is
> checked out anywhere (not in the primary worktree--which is the bug you
> are fixing) from getting updated but still allow an unborn branch to be
> updated, and then have patch 4/3 that forbids an update to even an
> unborn branch "checked out" in any working tree?  This update to the
> test can then become part of patch 4/3.

I agree that this merits a regression test.

Thanks,
Dscho

>
> Thanks.
>

Junio C Hamano Feb. 14, 2020, 3:03 p.m. UTC | #4

Johannes Schindelin <[e-mail]> writes:

>> Can patch 3/3 be split into two,
>
> I actually don't think so. The `refs_resolve_unsafe()` function simply
> ...
> In other words, a fix for one bug would be a fix for the other, and
> (probably) vice versa.

What mislead me was the way this step presented itself.  It sounded
as if the primary (and possibly the only) thing the series wanted to
fix was to make .denyCurrentBranch pay attention to other worktrees,
and while fixing that, it broke as collateral damage a "feature"
that denyCurrentBranch allows an unborn branch to be updated no
matter what and called it a bugfix when it was not a bug.

If the series is fixing two bugs, perhaps 2/3 can first fix it for a
primary worktree case by seeing what HEAD symref for the primary
worktree points at is the target of a push without iterating over
all the worktrees, have the test change in 2/3 (i.e. "fixing the
'unborn' case revealed a wrong expectation in an existing test"),
and a couple of new tests to see what a push from sideways would do
to an unborn branch that is checked out in the primary worktree when
.denyCurrentBranch is and isn't in effect.

Then 3/3 can use the same logic to see if one worktree is OK with
the proposed ref update by the push used in 2/3 (which no longer
uses refs_resolve_unsafe()') to check for all worktrees.  The new
tests introduced in 2/3 would be extended to see what happens when
the unborn branch getting updated by the push happens to be checked
out in a secondary worktree.

That would have avoided misleading this reader.

Thanks.

Hariom verma Feb. 15, 2020, 9:52 p.m. UTC | #5

On Fri, Feb 14, 2020 at 8:33 PM Junio C Hamano <[e-mail]> wrote:
> If the series is fixing two bugs, perhaps 2/3 can first fix it for a
> primary worktree case by seeing what HEAD symref for the primary
> worktree points at is the target of a push without iterating over
> all the worktrees, have the test change in 2/3 (i.e. "fixing the
> 'unborn' case revealed a wrong expectation in an existing test"),
> and a couple of new tests to see what a push from sideways would do
> to an unborn branch that is checked out in the primary worktree when
> .denyCurrentBranch is and isn't in effect.
>
> Then 3/3 can use the same logic to see if one worktree is OK with
> the proposed ref update by the push used in 2/3 (which no longer
> uses refs_resolve_unsafe()') to check for all worktrees.  The new
> tests introduced in 2/3 would be extended to see what happens when
> the unborn branch getting updated by the push happens to be checked
> out in a secondary worktree.

As far as my understanding goes, what we want is:
1) fixing `.denyCurrentBranch` for unborn branches in primary worktree. (2/3)
2) writing test (expect it to fail if `unborn` & 'non-bare' case) (2/3)
3) making `.denyCurrentBranch` respect all worktrees. (3/3)
4) extending tests written in step 2 for secondary worktrees. (3/3)

Correct me if I'm wrong.
As I'm not entirely familiar with working and structure of
`.denyCurrentBranch`. So I might need more explicit explanation.

Thanks,
Hariom

Junio C Hamano Feb. 16, 2020, 11:49 p.m. UTC | #6

Hariom verma <[e-mail]> writes:

> On Fri, Feb 14, 2020 at 8:33 PM Junio C Hamano <[e-mail]> wrote:
>> If the series is fixing two bugs, perhaps 2/3 can first fix it for a
>> primary worktree case by seeing what HEAD symref for the primary
>> worktree points at is the target of a push without iterating over
>> all the worktrees, have the test change in 2/3 (i.e. "fixing the
>> 'unborn' case revealed a wrong expectation in an existing test"),
>> and a couple of new tests to see what a push from sideways would do
>> to an unborn branch that is checked out in the primary worktree when
>> .denyCurrentBranch is and isn't in effect.
>>
>> Then 3/3 can use the same logic to see if one worktree is OK with
>> the proposed ref update by the push used in 2/3 (which no longer
>> uses refs_resolve_unsafe()') to check for all worktrees.  The new
>> tests introduced in 2/3 would be extended to see what happens when
>> the unborn branch getting updated by the push happens to be checked
>> out in a secondary worktree.
>
> As far as my understanding goes, what we want is:
> 1) fixing `.denyCurrentBranch` for unborn branches in primary worktree. (2/3)
> 2) writing test (expect it to fail if `unborn` & 'non-bare' case) (2/3)
> 3) making `.denyCurrentBranch` respect all worktrees. (3/3)
> 4) extending tests written in step 2 for secondary worktrees. (3/3)
>
> Correct me if I'm wrong.

If the above is what _you_ want, then there is nothing for me to
correct ;-)

What I suggested was somewhat different, though.

  1) get_main_worktree() fix you have as [1/3] in the current round.

  2) fix `.denyCurrentBranch` for unborn branches in the primary
     worktree, new tests for the cases I outlined in the message you
     are responding to, and adjusting the test (i.e. what you have
     as [2/3] in the current round).

  3) fix `.denyCurrentBranch` to pay attention to HEAD of not just
     the primary worktree but of all the worktrees, and add tests.

Thanks.

Hariom verma Feb. 22, 2020, 10:54 p.m. UTC | #7

On Mon, Feb 17, 2020 at 5:19 AM Junio C Hamano <[e-mail]> wrote:
> What I suggested was somewhat different, though.
>
>   1) get_main_worktree() fix you have as [1/3] in the current round.
>
>   2) fix `.denyCurrentBranch` for unborn branches in the primary
>      worktree, new tests for the cases I outlined in the message you
>      are responding to, and adjusting the test (i.e. what you have
>      as [2/3] in the current round).
>
>   3) fix `.denyCurrentBranch` to pay attention to HEAD of not just
>      the primary worktree but of all the worktrees, and add tests.

I doubt that it's possible to solve these 2 issues separately.
As dscho said: "a fix for one bug would be a fix for the other, and
(probably) vice versa."

As I discussed with dscho, the best possible solution for this
situation is to demonstrate the bug and fix it in succeeding commit.

I have sent this v2[1] for this patch.

Thanks,
Hariom

[1]: https://lore.kernel.org/git/[e-mail]/

Patch

diff --git a/t/t5509-fetch-push-namespaces.sh b/t/t5509-fetch-push-namespaces.sh
index 75cbfcc392..e3975bd21d 100755
--- a/t/t5509-fetch-push-namespaces.sh
+++ b/t/t5509-fetch-push-namespaces.sh
@@ -20,7 +20,7 @@  test_expect_success setup '
 	) &&
 	commit0=$(cd original && git rev-parse HEAD^) &&
 	commit1=$(cd original && git rev-parse HEAD) &&
-	git init pushee &&
+	git init --bare pushee &&
 	git init puller
 '