The native backend is just a proof of concept and there's no real
reason to use it other than for testing, so let's reduce the risk of
accidentally creating repos using it.
I was initially worried about the cost of always snapshotting the
working copy, so that's why e.g. `jj diff -r <some hash>` doesn't do
it. However, there's been a few caused by missing snapshotting, and
there are still a few (I just noticed it in `jj undo` while writing
this patch). Let's always do the snapshotting and if the user really
doesn't want it, they can pass `--no-commit-working-copy` (which we
should probably rename to `--no-snapshot-working-copy` or maybe just
`--no-snapshot`). That should reduce bugs and make the CLI more
predictable.
Two test cases were affected becasue `jj merge` also didn't snapshot
the working copy.
Before this patch, e.g. `jj co --no-commit-working-copy` would error
out, but now it will succeed (without touching the working copy,
leaving the working copy stale). That may be confusing, but it should
be easy to recover from (e.g. by `jj undo`). We can consider adding a
check for it later if it seems too confusing (it's probably rarely
something the user wanted).
We didn't have any testing of exit codes on failure, other than
checking that they were not 0. This patch changes that so we always
check. Since we have the special exit code 2 (set by `clap`) for
incorrect command line, I've replaced some testing of error messages
by testing of just the exit code.
As part of this, I also fixed `jj branch --allow-backwards` to
actually require `-r` (it didn't before because having a default value
means the argument is considered always provided).
This adds a `jj sparse` command with options to list and manage the
set of paths to include in the working copy. It only supports includes
(postive matches) for now.
I'm not sure "sparse" is the best name for the feature. Perhaps it
would make sense as a subcommand under `jj workspace` - maybe `jj
workspace track`? However, there's also `jj untrack` for removing a
file from the working copy and leaving it in the working copy. I'm
happy to hear suggestions, or we can get back to the naming later.
It seems very unlikely that the user would want to untrack all paths
(that's still possible with `jj untrack .`, if they really want to,
and have added all their current paths to the `.gitignore`).
We very often expect success, and we sometimes want to get the stdout,
too. Let's add a convenience function for that. It saves a lot of
lines of code.
As pointed out by @arxanas in #88, the message saying something like
"At least 'bin/.DS_Store' was added back ..." is confusing especially
when the command you ran was just `jj untrack bin/.DS_Store`. Let's
clarify the message by saying exactly how many more files there are,
and specialize the message for when there is only one file. Also
update the message to say "would be added back" instead of "was added
back" since we don't actually change anything if some files would be
added back (since 4b91ad408c).
Should we even list all the files? I'm concerned that such a list
could be very long. On the other hand, it can also be annoying to have
to run `jj untrack some/dir/` and only be told about single file to
add to the ignore patterns every time.
