Hi Emily,
On Mon, 1 Jul 2019, Emily Shaffer wrote:
> Teach transport-helper how to notice if skipping a ref during push would
> violate atomicity on the client side. We notice that a ref would be
> rejected, and choose not to send it, but don't notice that if the client
> has asked for --atomic we are violating atomicity if all the other
> pushes we are sending would succeed. Asking the server end to uphold
> atomicity wouldn't work here as the server doesn't have any idea that we
> tried to update a ref that's broken.
Makes sense.
> The added test-case is a succinct way to reproduce this issue that fails
> today. The same steps work fine when we aren't using a transport-helper
> to get to the upstream, i.e. when we've added a local repository as a
> remote:
>
> git remote add ~/upstream upstream
>
> Signed-off-by: Emily Shaffer <emilyshaf...@google.com>
> ---
> t/t5541-http-push-smart.sh | 58 ++++++++++++++++++++++++++++++++++++++
> transport-helper.c | 6 ++++
> transport.c | 15 +++++++++-
> 3 files changed, 78 insertions(+), 1 deletion(-)
>
> diff --git a/t/t5541-http-push-smart.sh b/t/t5541-http-push-smart.sh
> index 8ef8763e06..b57f6d480f 100755
> --- a/t/t5541-http-push-smart.sh
> +++ b/t/t5541-http-push-smart.sh
> @@ -177,6 +177,64 @@ test_expect_success 'push (chunked)' '
> test $HEAD = $(git rev-parse --verify HEAD))
> '
>
> +test_expect_success 'push --atomic also prevents branch creation' '
> + # Make up/master
> + d=$HTTPD_DOCUMENT_ROOT_PATH/atomic-branches.git &&
> + git init --bare "$d" &&
> + git --git-dir="$d" config http.receivepack true &&
Why not `-C "$d"`? And why not `test_config`?
> + up="$HTTPD_URL"/smart/atomic-branches.git &&
> + test_commit atomic1 &&
> + test_commit atomic2 &&
> + git push "$up" master &&
It would be more succinct to do a `git clone --bare . "$d"` here, instead
of a `git init --bare` and a `git push` no?
> + # Make master incompatible with up/master
> + git reset --hard HEAD^ &&
> + # Add a new branch
> + git branch atomic &&
> + # --atomic should roll back creation of up/atomic
> + test_must_fail git push --atomic "$up" master atomic &&
> + git ls-remote "$up" >up-remotes &&
> + test_must_fail grep atomic up-remotes
Why not `test_must_fail git -C "$d" rev-parse refs/heads/atomic`?
> +'
> +
> +test_expect_success 'push --atomic shows all failed refs' '
> + # Make up/master, up/allrefs
> + d=$HTTPD_DOCUMENT_ROOT_PATH/atomic-failed-refs.git &&
> + git init --bare "$d" &&
> + git --git-dir="$d" config http.receivepack true &&
> + up="$HTTPD_URL"/smart/atomic-failed-refs.git &&
> + test_commit allrefs1 &&
> + test_commit allrefs2 &&
> + git branch allrefs &&
> + git push "$up" master allrefs &&
> + # Make master and allrefs incompatible with up/master, up/allrefs
> + git checkout allrefs &&
> + git reset --hard HEAD^ &&
> + git checkout master &&
> + git reset --hard HEAD^ &&
> + # --atomic should complain about both master and allrefs
> + test_must_fail git push --atomic "$up" master allrefs >&output &&
> + grep master output &&
> + grep allrefs output
> +'
I have the impression that the setup these two new test cases perform are
_very_ similar, making it most likely that a combined test case would be
more succinct, yet still complete and easily readable.
> +
> +test_expect_success 'push --atomic indicates collateral failures' '
> + # Make up/master, up/collateral
> + d=$HTTPD_DOCUMENT_ROOT_PATH/atomic-collateral.git &&
> + git init --bare "$d" &&
> + git --git-dir="$d" config http.receivepack true &&
> + up="$HTTPD_URL"/smart/atomic-collateral.git &&
> + test_commit collateral1 &&
> + test_commit collateral2 &&
> + git branch collateral &&
> + git push "$up" master collateral &&
> + # Make master incompatible with up/master
> + git reset --hard HEAD^ &&
> + # --atomic should mention collateral was OK but failed anyway
> + test_must_fail git push --atomic "$up" master collateral >&output &&
> + grep "master -> master" output &&
> + grep "collateral -> collateral" output
> +'
Same here.
> +
> test_expect_success 'push --all can push to empty repo' '
> d=$HTTPD_DOCUMENT_ROOT_PATH/empty-all.git &&
> git init --bare "$d" &&
> diff --git a/transport-helper.c b/transport-helper.c
> index c7e17ec9cb..6b05a88faf 100644
> --- a/transport-helper.c
> +++ b/transport-helper.c
> @@ -853,6 +853,7 @@ static int push_refs_with_push(struct transport
> *transport,
> {
> int force_all = flags & TRANSPORT_PUSH_FORCE;
> int mirror = flags & TRANSPORT_PUSH_MIRROR;
> + int atomic = flags & TRANSPORT_PUSH_ATOMIC;
> struct helper_data *data = transport->data;
> struct strbuf buf = STRBUF_INIT;
> struct ref *ref;
> @@ -872,6 +873,11 @@ static int push_refs_with_push(struct transport
> *transport,
> case REF_STATUS_REJECT_NONFASTFORWARD:
> case REF_STATUS_REJECT_STALE:
> case REF_STATUS_REJECT_ALREADY_EXISTS:
> + if (atomic) {
> + string_list_clear(&cas_options, 0);
> + return 0;
> + } else
> + continue;
> case REF_STATUS_UPTODATE:
> continue;
> default:
> diff --git a/transport.c b/transport.c
> index f1fcd2c4b0..f4d6b38f9d 100644
> --- a/transport.c
> +++ b/transport.c
> @@ -1226,10 +1226,23 @@ int transport_push(struct repository *r,
> err = push_had_errors(remote_refs);
> ret = push_ret | err;
>
> - if (!quiet || err)
> + if ((flags & TRANSPORT_PUSH_ATOMIC) && err) {
This looks funny. And it does so only...
> + for (struct ref *it = remote_refs; it; it = it->next)
> + switch (it->status) {
> + case REF_STATUS_NONE:
> + case REF_STATUS_UPTODATE:
> + case REF_STATUS_OK:
> + it->status =
> REF_STATUS_ATOMIC_PUSH_FAILED;
> + default:
> + continue;
> + }
> + }
> +
> + if (!quiet || err) {
... because a curly was introduced around a single-liner. This adds
unnecessary noise to the patch.
This easily distracts reviewers like myself from more important questions
such as: why was this conditional switch added before this conditional
block, does it intend to influence the printed push status? Ah, yes, of
course, even if `it->status` is changed, it actually modifies the data
to which `remote_refs` points. So yes, this has to be done here.
> transport_print_push_status(transport->url, remote_refs,
> verbose | porcelain, porcelain,
> reject_reasons);
> + }
>
> if (flags & TRANSPORT_PUSH_SET_UPSTREAM)
> set_upstreams(transport, remote_refs, pretend);
> --
Apart from minor nits, I like it. Thanks,
Dscho
> 2.22.0.410.gd8fdbe21b5-goog
>
>
