Apparently, it gets too verbose if the remote history is actively rewritten.
Let's summarize the output for now. The plan is to show the list of moved refs
instead of the full list of abandoned commits.
The problem is that the first non-working-copy commit moves the unborn current
branch to that commit, but jj doesn't "export" the moved branch. Therefore,
the next jj invocation notices the "external" ref change, which was actually
made by jj.
I'm not sure why we play nice by setting the "current" HEAD, but I *think* it's
okay to set the "new" HEAD and reset to the same commit to clear Git index.
This will probably help to understand why you've got conflicts after fetching.
Maybe we can also report changed local refs.
I think the stats should be redirected to stderr, but we have many other similar
messages printed to stdout. I'll probably fix them all at once later.
This adds a new `revset-aliases.immutable_heads()s` config for
defining the set of immutable commits. The set is defined as the
configured revset, as well as its ancestors, and the root commit
commit (even if the configured set is empty).
This patch also adds enforcement of the config where we already had
checks preventing rewrite of the root commit. The working-copy commit
is implicitly assumed to be writable in most cases. Specifically, we
won't prevent amending the working copy even if the user includes it
in the config but we do prevent `jj edit @` in that case. That seems
good enough to me. Maybe we should emit a warning when the working
copy is in the set of immutable commits.
Maybe we should add support for something more like [Mercurial's
phases](https://wiki.mercurial-scm.org/Phases), which is propagated on
push and pull. There's already some affordance for that in the view
object's `public_heads` field. However, this is simpler, especially
since we can't propagate the phase to Git remotes, and seems like a
good start. Also, it lets you say that commits authored by other users
are immutable, for example.
For now, the functionality is in the CLI library. I'm not sure if we
want to move it into the library crate. I'm leaning towards letting
library users do whatever they want without being restricted by
immutable commits. I do think we should move the functionality into a
future `ui-lib` or `ui-util` crate. That crate would have most of the
functionality in the current `cli_util` module (but in a
non-CLI-specific form).
I made it simply fail on explicit fetch/import, and ignored on implicit import.
Since the error mode is predictable and less likely to occur. I don't think it
makes sense to implement warning propagation just for this.
Closes#1690.
