Displaying 2 Slate components with the same initialValue breaks the page

[grose-dg]

Description
Using slate 0.123.0, when rendering 2 components with the same value reference, we get an error in the findPath function :
Unable to find the path for Slate node: {"text":"This is editable "}
at Object.findPath (http://localhost:3000/static/js/bundle.js:23324:11)
at Object.toSlatePoint (http://localhost:3000/static/js/bundle.js:23689:26)
at Object.toSlateRange (http://localhost:3000/static/js/bundle.js:23795:28)
at setDomSelection (http://localhost:3000/static/js/bundle.js:27951:38)
at http://localhost:3000/static/js/bundle.js:28003:7
at Object.react_stack_bottom_frame (http://localhost:3000/static/js/bundle.js:18667:18)
at runWithFiberInDEV (http://localhost:3000/static/js/bundle.js:5954:68)
at commitHookEffectListMount (http://localhost:3000/static/js/bundle.js:11958:157)
at commitHookLayoutEffects (http://localhost:3000/static/js/bundle.js:11945:56)
at commitLayoutEffectOnFiber (http://localhost:3000/static/js/bundle.js:12314:22)

This was not the case with previous versions.

Recording

Steps
See the gif above :
Have 2 components rendered with the same initialValue reference (if we stringify both values we bypass the issue).

Expectation
We can display the same value multiple times on the same page as we did before slate-dom 0.123.0 (0.119 and prior).

Environment

• Slate Version: 0.123.0
• Operating System: Windows
• Browser: Chrome / Firefox

[12joan]

We don't currently support displaying the same Slate value in two editors concurrently. I'm not sure what might have changed between slate-dom@0.119 and 0.123.0 to cause this error to be thrown, but even before then, reusing the same Slate value would have resulted in subtle bugs.

This is because Slate uses node objects as WeakMap keys in various places, such as to map Slate nodes to DOM elements. These weak maps are not specific to the editor object, so multiple editors will unfortunately read and overwrite the weak map entries created by one another. This can result in crashes in some cases (as you've seen), but also more subtle bugs that are very difficult to reproduce and debug.

The best workaround is to deeply clone your Slate value before using it in either editor.

If you want to try fixing this, you could try making Slate's weak maps editor-specific, so instead of a WeakMap<Node, DOMElement>, for example, you would have a WeakMap<Editor, WeakMap<Node, DOMElement>>.

[grose-dg]

The change that broke our usage is in the slate-dom -> dom-editor.ts -> findPath function :

slate/packages/slate-dom/src/plugin/dom-editor.ts

Line 390 in 591f8d6

findPath: (editor, node) => {

The check if (Editor.isEditor(child)) was replaced by if (child === editor) resulting in not returning the path in our use case.

We did not notice any bugs (even subtle, but that's the issue with subtle bugs) when using it before this version but we acknowledge that our usage is not aligned with what Slate offers.

Thank you for your answer, we will update our usage 👍