Implement relative line numbers

[sergeichestakov]

Implement relative line numbers

[nightwing]

@sergeichestakov this is quite easy to implement

import { lineNumbers } from '@codemirror/view';

function formatNumber() {
  return lineNumbers({
    formatNumber: (lineNo, state) => {
      if (lineNo > state.doc.lines) {
        return lineNo;
      }
      const cursorLine = state.doc.lineAt(state.selection.asSingle().ranges[0].to).number;
      if (lineNo === cursorLine) {
        return lineNo < 10 ? lineNo + "\xB7" : lineNo + "";
      } else {
        return Math.abs(cursorLine - lineNo).toString();
      }
    },
  });
}

We probably can use a compartment to include this in vim extension and make it configurable via set relativenumber

But i am not sure how to make this work for set number, as it is already part of basicSetup

[sergeichestakov]

awesome, nice! yeah as for the conflict I think we can try to give it a higher precedence then the line numbers gutter that ships with basicSetup. Otherwise, if that doesn't work, I think it's ok to assume that most users of this extension have more complex use cases that don't involve just using basicSetup and / or are able to filter out the relevant extension if need be. I think wrapping in the right Prec should do the trick though