Problem: when running the sync protocol for a new document the API
requires that the user create an empty document and then call
`receive_sync_message` on that document. This results in the OpObserver
for the new document being called with every single op in the document
history. For documents with a large history this can be extremely time
consuming, but the OpObserver doesn't need to know about all the hidden
states.
Solution: Modify `Automerge::load_with` and
`Automerge::apply_changes_with` to check if the document is empty before
applying changes. If the document _is_ empty then we don't call the
observer for every change, but instead use
`automerge::observe_current_state` to notify the observer of the new
state once all the changes have been applied.
The new text features are faster and more ergonomic but not backwards
compatible. In order to make them backwards compatible re-expose the
original functionality and move the new API under a `future` export.
This allows users to interoperably use both implementations.
The wasm codebase assumed that clients want to represent text as a
string of characters. This is faster, but in order to enable backwards
compatibility we add a `TextRepresentation` argument to
`automerge_wasm::Automerge::new` to allow clients to choose between a
`string` or `Array<any>` representation. The `automerge_wasm::Observer`
will consult this setting to determine what kind of diffs to generate.
The tsconfig.json was setup to not include the JS tests. Update the
config to include the tests when checking typescript and fix all the
consequent errors. None of this is semantically meaningful _except_ for
a few incorrect usages of the API which were leading to flaky tests.
Hooray for types!
Transactions with no ops in them are generally undesirable. They take up
space in the change log but do nothing else. They are not useless
though, it may occasionally be necessary to create an empty change in
order to list all the current heads of the document as dependents of the
empty change.
The current API makes no distinction between empty changes and non-empty
changes. If the user calls `Transaction::commit` a change is created
regardless of whether there are ops to commit. To provide a more useful
API modify `commit` so that if there is a no-op transaction then no
changes are created, but provide explicit methods to create an empty
change via `Transaction::empty_change`, `Automerge::empty_change` and
`Autocommit::empty_change`. Also make these APIs available in Javascript
and C.
The logic for `clone` which was updated to support cloning a viewed
document inadverantly left the heads of the cloned document state in
place, which meant that cloned documents could not be `change`d. Set
state.heads to undefined when cloning to allow changing them.
Sometimes you need a cheap copy of a document at a given set of heads
just so you can see what has changed. Cloning the document to do this is
quite expensive when you don't need a writable copy. Add automerge.view
to allow a cheap read only copy of a document at a given set of heads
and add an additional heads argument to clone for when you do want a
writable copy.
Continuing our theme of treating all languages equally, move
wrappers/javascript to javascrpit. Automerge libraries for new languages
should be built at this top level if possible.
