Comment 2 for bug 1763639

I misused the term branch here. On the Launchpad side, only a tarball should be created and stored. I'll rename the bug accordingly. Actually creating a VCS branch from that is optionally done by a person when and if that is necessary.

This mechanism is indeed meant for recovery purposes only. Not something to be maintained frequently but if there's no better option than to apply an urgent patch on the existing sources. Pulling in a new version of the same snap might contain any number of changes. By the same token, patching and re-building the same snap from source may pull in different dependencies or rely on external sources no longer available.

The result of "snapcraft pull" is actually to be taken as-is here. The entire folder should be copied. After running it, all artifacts will be contained in the project tree. When building from this copy, Snapcraft can detect that all dependencies are already satisfied and will build from it without reaching out to the network to retrieve them. No modifications to the snapcraft.yaml are therefore necessary.