We don't want variables from the developer's environment to affect
tests. You can make tests fail if you set `XDG_CONFIG_HOME` such that
`$XDG_CONFIG_HOME/jj/config.toml` exists and has e.g. an email
set. The fix is to not propagate any environment variables. Thanks for
@arxanas for pointing this out in #104.
We still need to set `$HOME` to prevent configs from being read from
the process owner's home directory (because that's what
`dirs::config_dir()` seems to fall back to if `$HOME` is not set). By
the way, I suspect we'd still not immune to configs from the
developers home directory on Windows, because that doesn't seem to be
controlled by `$HOME`.
This patch introduces a `JJ_TIMESTAMP` environment variable that lets
us specify the timestamp to use in tests. It also updates the tests to
use it, which means we get to simplify the tests a lot now that that
the hashes are predictable.
The auto-rebasing of descendants doesn't work if you have an open
commit checked out, which means that you may still end up with orphans
in that case (though that's usually a short-lived problem since they
get rebased when you close the commit). I'm also about to make
branches update to successors, but that also doesn't work when the
branch is on a working copy commit that gets rewritten. To fix this
problem, I've decided to let the caller of `WorkingCopy::commit()`
responsible for the transaction.
I expect that some of the code that this change moves from the lib
crate to the cli crate will later move back into the lib crate in some
form.
I just changed my `~/.gitignore` and some tests started failing
because the working copy respects the user's `~/.gitignore`. We should
probably not depend on `$HOME` in the library crate. For now, this
patch just makes sure we set it to an arbitrary directory in the tests
where it matters.
I'm preparing to publish an early version before someone takes the
name(s) on crates.io. "jj" has been taken by a seemingly useless
project, but "jujube" and "jujube-lib" are still available, so let's
use those.
