upgrade: Use `improvement` subclasses everywhere, not instances This changes the source definition of optimizations to match that of formats: a subclass with a decorator, instead of an instance passed to a function call. Not having any instance removes the confusion between class attributes and instance attributes, which were used interchangeably. Differential Revision: https://phab.mercurial-scm.org/D10768

tests: monkeypatch `util.get_password()` to avoid deadlocks on Windows This should have been part of 5b3513177f2b. Differential Revision: https://phab.mercurial-scm.org/D10759

rust-status: fix ignore and include not composing (issue6514) While the fix is pretty simple, the overall dispatch logic has become kind of ugly. Thankfully we're currently upstreaming a better algorithm, this code is temporary anyway. Differential Revision: https://phab.mercurial-scm.org/D10639

rust-status: highlight a bug in Rust-augmented status This was reported in issue6514, confirmed with this test reproduction. This will be fixed with the next changeset. Differential Revision: https://phab.mercurial-scm.org/D10638