Atomic(non-editable) Nodes and ReplaceSteps

raphaelsantos · April 12, 2021, 1:50pm

Hello,

We have implemented a few components in our PM editor where we use atom Nodes along with custom NodeViews to support interactive components that are not editable within ProseMirror but can be edited within a separate editor. The authored data is assigned to the Node’s attributes and in order to update the EditorState we are using Transaction.replaceWith(), passing the updated Node when the custom Editor is closed.

This approach seems to be working fine except for fact that Undo/Redo steps are not generated. I was navigating the source code and it seems to be due to the fact that ReplaceSteps are not created when the replaced slice is “empty”.

github.com

ProseMirror/prosemirror-transform/blob/d287e899403dad60dc7e718206d401ee96010afe/src/replace.js#L13


import {ReplaceStep, ReplaceAroundStep} from "./replace_step"
import {Transform} from "./transform"
import {insertPoint} from "./structure"

// :: (Node, number, ?number, ?Slice) → ?Step
// ‘Fit’ a slice into a given position in the document, producing a
// [step](#transform.Step) that inserts it. Will return null if
// there's no meaningful way to insert the slice here, or inserting it
// would be a no-op (an empty slice over an empty range).
export function replaceStep(doc, from, to = from, slice = Slice.empty) {
  if (from == to && !slice.size) return null

  let $from = doc.resolve(from), $to = doc.resolve(to)
  // Optimization -- avoid work if it's obvious that it's not needed.
  if (fitsTrivially($from, $to, slice)) return new ReplaceStep(from, to, slice)
  return new Fitter($from, $to, slice).fit()
}

// :: (number, ?number, ?Slice) → this
// Replace the part of the document between `from` and `to` with the
// given `slice`.

Since the approach we’re using makes the Nodes “empty” (as all the data is stored in its attributes), this condition is not met and a ReplaceStep is not created, preventing the undo/redo from being enabled.

Any sugestions on how to “circumvent” this? I also wonder if the approach with atom Nodes storing data in attributes make sense for the purpose I describe above (content edited in an editor external to PM).

Thanks,

marijn · April 12, 2021, 3:23pm

and the range that is replaced is empty. A replace step that replaces nothing with nothing would have no effect, and can’t change attributes either, so I think you might be misdiagnosing the issue here?