If I return an EditorView.scrollIntoView effect from a transactionExtender, then my StateField’s start throwing errors when they update themselves!
My state field is an object containing a DecorationSet as a property. Something like this:
const myStateField = StateField.define({
// intialise state field with a range that covers the entire editor
create: (state) => ({
set: Decoration.set([myMark.range(0, state.doc.length)])
}),
// update it as changes occur
update: (val, tr) => {
val.set = val.set.map(tr.changes);
return val;
},
});
Everything works when I return a new object from myStateField.update, but if I just update the existing one and return that, then it breaks. I suppose these StateField objects must always return a new instance of an object?
To make things very clear:
// this throws:
update: (val, tr) => {
val.set = val.set.map(tr.changes);
return val;
},
// this works:
update: (val, tr) =>
return { set: val.set.map(tr.changes) };
},
I suppose CodeMirror is internally re-using the objects created by my StateField? Is this why it’s failing?
I’ve been able to make a small reproducible example here: Try CodeMirror