The existing code was really difficult to reason about:
- The default notetype depended on the selected deck, and vice versa,
and this logic was buried in the deck and notetype choosing screens,
and models.py.
- Changes to the notetype were not passed back directly, but were fired
via a hook, which changed any screen in the app that had a notetype
selector.
It also wasn't great for performance, as the most recent deck and tags
were embedded in the notetype, which can be expensive to save and sync
for large notetypes.
To address these points:
- The current deck for a notetype, and notetype for a deck, are now
stored in separate config variables, instead of directly in the deck
or notetype. These are cheap to read and write, and we'll be able to
sync them individually in the future once config syncing is updated in
the future. I seem to recall some users not wanting the tag saving
behaviour, so I've dropped that for now, but if people end up missing
it, it would be simple to add as an extra auxiliary config variable.
- The logic for getting the starting deck and notetype has been moved
into the backend. It should be the same as the older Python code, with
one exception: when "change deck depending on notetype" is enabled in
the preferences, it will start with the current notetype ("curModel"),
instead of first trying to get a deck-specific notetype.
- ModelChooser has been duplicated into notetypechooser.py, and it
has been updated to solely be concerned with keeping track of a selected
notetype - it no longer alters global state.
This splits update_card() into separate undoable/non-undoable ops
like the change to notes in b4396b94abdeba3347d30025c5c0240d991006c9
It means that actions get a blanket 'Update Card' description - in the
future we'll probably want to either add specific actions to the backend,
or allow an enum or string to be passed in to describe the op.
Other changes:
- card.flush() can no longer be used to add new cards. Card creation
is only supposed to be done in response to changes in a note's fields,
and this functionality was only exposed because the card generation
hadn't been migrated to the backend at that point. As far as I'm aware,
only Arthur's "copy notes" add-on used this functionality, and that should
be an easy fix - when the new note is added, the associated cards will
be generated, and they can then be retrieved with note.cards()
- tidy ups/PEP8
To coalesce successive note edits into a single undo op we'll need to
be able to get the original Undoable type, which is awkward to do with
a trait object.
- note.flush() behaves like before, as otherwise actions or add-ons
that perform bulk flushing would end up creating an undo entry for
each note
- added col.update_note() to opt in to the new behaviour
- tidy up the names of some related routines
- transact() now automatically clears card queues unless an op
opts-out (and currently only AnswerCard does). This means there's no
risk of forgetting to clear the queues in an operation, or when undoing/
redoing
- CollectionOp->UndoableOp
- clear queues when redoing "answer card", instead of clearing redo
when clearing queues
Reviews and operations on the backend that support undoing can now be
committed immediately, so they will not be lost in the event of a crash.
This required tweaks to a few places:
- don't set collection mtime on save() unless changes were made in
Python, as otherwise we end up accidentally clearing the backend undo
queue
- autosave() is now run on every reset()
- garbage collection now runs in a timer, instead of relying on
autosave() to be run periodically
- use dataclasses for the review/checkpoint undo cases, instead of the
nasty ad-hoc list structure
- expose backend review undo to Python, and hook it into GUI
- redo is not currently exposed on the GUI, and the backend can only
cope with reviews done by the new scheduler at the moment
- the initial undo prototype code was bumping mtime/usn on undo, but
that was not ideal, as it was breaking the queue handling which expected
the mtime to match. The original rationale for bumping mtime/usn was
to avoid problems with syncing, but various operations like removing
a revlog can't be synced anyway - so we just need to ensure we clear the
undo queue prior to syncing
- fetch sfld and csum when fetching notes, to make it cheaper
to write them back out unmodified
- make `fields` private, and access it via accessors, so we can
still catch when fields have been mutated without calling
prepare_for_update()
- fix python importing code passing a string in as the checksum
