Add support for manual resizing

Sorry if this is a duplicate, but a quick search of the issue list found nothing that seemed related.

I was wondering if CodeMirror could be made to support the CSS resize attribute. So that I could write something like this:

.CodeMirror-scroll
{
    resize: vertical;
}

In the current release (2.34), this actually renders a resize handle, but I can’t move it. Or am I just doing it wrong?

[JoseTadeuMarques]

@Sphinxxxx use cm-resize 😃

[lunakid]

Guys, it’s a bit too early for the celebration just yet. 😉

@JoseTadeuMarques, unfortunately, what you see is not what you think: the CM instance is not actually resizing just by setting the CSS. What you describe and what you saw is only a HTML DIV resizing (which is quite unsurprising, adding a CSS rule for just that).

To understand what CM resizing really means, i.e. resizing the actual CM Javascript object (with all its geometry-related internal state), rather than just resizing a HTML box on the screen, see e.g. my demo at CodePen, where e.g. the line numbers + line wrapping clearly evidences how the editor properly recalculates its state with that method – which was necessary exactly because just setting CSS resize does not cut it. (I.e. it will not pass resize events to the CM instance to get it recalculate its state!)

(For those who want to understand the mechanics, please see the details in my original comment above.)