'Error: not implemented' when using array .splice() to remove items (but not add any)

[senseibaka]

Repro:

Replace this line

immer-yjs/packages/immer-yjs/src/immer-yjs.test.ts

Line 52 in 6b9eb37

d1.topping.splice(2, 2, { id: '7777', type: 'test1' }, { id: '8888', type: 'test2' })

with

d1.topping.splice(2, 2)

and then rerun the unit test

[senseibaka]

I've been digging into this a little bit, immer seems to send:

• [success] an array manipulation patch (i.e. remove items from the array)
• [error] a property change patch which specifies the path length has changed value

I'd suggest doing something around https://github.com/sep2/immer-yjs/blob/main/packages/immer-yjs/src/immer-yjs.ts#L107

Like

} else if (base instanceof Y.Array && property === 'length') {
    // no-op
} else {
    notImplemented();
}

[sep2]

Thank you for reporting! I will investigate into it. At the same time PR is welcome 😁

[senseibaka]

Thanks, if I get some time in the next few days I might work on it.

The problem is a little more complex by the way, I've observed in cases where you splice-remove the last item in an array, immer only supplies a patch for the changed length property, so the above suggestion wouldn't work in all cases.