Single line plugin

[vimtor]

Hi there! I've make this little plugin for limiting the editor to only have one line:

import { Transforms } from 'slate';

export const createSingleLinePlugin = () => ({
  onKeyDown: () => event => {
    if (event.key === 'Enter') {
      event.preventDefault();
    }
  },
  withOverrides: editor => {
    const { normalizeNode } = editor;

    editor.insertBreak = () => null;

    editor.normalizeNode = entry => {
      if (editor.children.length > 1) {
        Transforms.removeNodes(editor, {
          at: [],
          mode: 'highest',
          match: (node, path) => path[0] > 0,
        });
      }
      normalizeNode(entry);
    };

    return editor;
  },
});

It's an improved version of ianstormtaylor/slate#419 (comment) since it was giving me problems, specially on copy/paste.

If you want @zbeyens I can open a pull request adding it 😄

[zbeyens]

Super! It would fit well in the break package. PR is welcome! I gave you write access.

Another variation (withSingleBlock) would allow line breaks on insertBreak, a bit like social media posts/comments.

[vimtor]

Awesome! Love the name