Fix - withReact type signature

[e1himself]

Description
withReact() plugin type signature is inaccurate.

In reality, it accepts any editor instance implementing BaseEditor and extends it with additional ReactEditor API.

But the type definitions require to pass an instance that is already a ReactEditor.

The typical workaround is either to cast the instance with as ReactEditor or define the Editor custom type in the project. However, both are band-aid solutions to the real problem: invalid type spec of the withReact() function.

Issue
Fixes: #4144

Example

Before the fix:

After the fix:

Context

n/a

Checks

• The new code matches the existing patterns and styles.
• The tests pass with yarn test.
• The linter passes with yarn lint. (Fix errors with yarn fix.)
• The relevant examples still work. (Run examples with yarn start.)
• You've added a changeset if changing functionality. (Add one with yarn changeset add.)

[changeset-bot]

🦋 Changeset detected

Latest commit: 002e738

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
slate-react	Patch

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[dylans]

So this looks fine to me. I do believe there was a deliberate reason why they deliberately kept ReactEditor in BaseEditor but I'm not remembering what that was. Leaving this open for a couple of days in case anyone remembers why.

[e1himself]

I do believe there was a deliberate reason why they deliberately kept ReactEditor in BaseEditor but I'm not remembering what that was.

I am not sure if there was a reason.

If you look at the code before the patch:

slate/packages/slate-react/src/plugin/with-react.ts

Lines 38 to 39 in e927336

	export const withReact = <T extends Editor>(editor: T) => {
	const e = editor as T & ReactEditor

it's completely not obvious (or even unexpected) that it will result in this Typescript definition:

export declare const withReact: <T extends ReactEditor>(editor: T) => T & ReactEditor;

Note how <T extends Editor> became <T extends ReactEditor>.

[e1himself]

Leaving this open for a couple of days in case anyone remembers why.

👍

Thanks.