A few tests were failing which exposed the fact that if skip is `B` (the
out factor of the OpTree) then we set `skip = None` and this causes us
to attempt to return `Skip` in a non root node. I ported the failing
test from JS to Rust and fixed the problem.
I also fixed the formatting issues.
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.
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.
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.
After some discussion with PVH I realise that the repo structure in the
last reorg was very rust-centric. In an attempt to put each language on
a level footing move the rust code and project files into ./rust
