Git merge proposals silently show no diff if there are conflicts?

[James Troup]

Git merge proposals appear to silently show no diff if there are conflicts

Example branch (private, sorry):

https://code.launchpad.net/~deej/canonical-is-firewalls/+git/ols-jenkaas-slave-access-rt94226/+merge/302086

[William Grant (wgrant)]

This works in general. Have you seen this at all since?

[Launchpad Janitor (janitor)]

[Expired for Launchpad itself because there has been no activity for 60 days.]

[Данило Шеган (danilo)]

I've just seen this: I thought it might have been something else (I've seen lost diff generation jobs in the past) and I resubmitted an MP https://code.launchpad.net/~blake-rouse/maas/+git/maas/+merge/330591 so it ended up being https://code.launchpad.net/~blake-rouse/maas/+git/maas/+merge/331137.

Since this did not help, I dug deeper and noticed that there were conflicts between branches: maas master at 4a3a5b3115216212188b4f9e2e9e717efe8109b0 and Blake's proposed branch at 0cd57a8c1f103c9fec29d8688976b9c8769a2f5a:

$ git pull https://git.launchpad.net/~blake-rouse/maas refs/heads/split-webui-tabs
From https://git.launchpad.net/~blake-rouse/maas
 * branch split-webui-tabs -> FETCH_HEAD
CONFLICT (modify/delete): src/maasserver/static/partials/nodes-list.html deleted in 0cd57a8c1f103c9fec29d8688976b9c8769a2f5a and modified in HEAD. Version HEAD of src/maasserver/static/partials/nodes-list.html left in tree.
Auto-merging src/maasserver/static/js/angular/controllers/tests/test_nodes_list.js
Auto-merging src/maasserver/static/js/angular/controllers/nodes_list.js
Automatic merge failed; fix conflicts and then commit the result.

[Colin Watson (cjwatson)]

This appears to be managing to trigger a segfault in pygit2. I dug out deej's old branch and it does the same thing. Not all conflicts are affected; the examples I have so far are those where the "theirs" side of the conflict entry in the merged index is None.