Simplify the Enter behavior in Markdown lists to only support “tight” lists

[yurivish]

(Not sure if this is the right place to report this issue since it's about the Desktop code editor, lmk if there's a better place and I'll move it!)

When it comes to lists, Observable's Markdown code editor has a few behaviors that I found surprising:

1. Pressing enter twice past the end of a list results in an (imo) incorrect state with a newline after the list followed by an extra -:

2. It will delete a list item if you press enter in a line containing - :

There's a wide range of preferences when it comes to editing so I'm not sure if these are bugs.

I sometimes use a markdown cell as a scratch space to maintain ideas and to-do items inside a notebook and would appreciate it if there was a way to tweak this behavior slightly. For 1., I would like pressing Enter twice to not insert any additional content beyond the newlines, and for 2., it would be nice if it did not delete the empty list item.

[mbostock]

Thanks for the feedback! I’m pretty sure this is the default behavior of CodeMirror’s Markdown extension (and likely the same behavior as in the Notebooks 1.0 web editor), but I can investigate to see how easy it is to change. I agree with your suggestions.

[yurivish]

That's great! 🙏

Btw I've been playing around with Desktop over the past week and it's fantastic – having the Observable editor experience on top of a standalone local file in open format is really great.

[mbostock]

I took a look at the source: https://github.com/codemirror/lang-markdown/blob/main/src/commands.ts

This behavior seems intentional. In the first case, it is to turn a “tight” (single-spaced) list into a “loose” (double-spaced) list where each item is a paragraph. Hitting enter a third time will clear the list markup to return you to a normal paragraph. And I believe that latter part explains the second case, albeit in the degenerate case of an empty list.

Maybe it’s a little unexpected, but it does make it easier to create double-spaced lists. Do you think you can learn this behavior or would you still want it changed? I’m not sure what alternative would maintain the intended behavior from CodeMirror’s side.

[yurivish]

Looking at the Markdown editing behavior in Notion and Bear and iA Writer, all three have the second behavior of the "disappearing list item" (which struck me as odd but I don't actually mind), while none have the first behavior (which I've run into hundreds of times in the Observable editor and has felt like a papercut every time).

I've never intentionally made a "loose" list and based on circumstantial evidence think it is possible that many people are not aware of the difference and wouldn’t mind if were a litttle harder to make loose lists.

If it were up to me I'd probably change the default to match Notion/Bear/iA Writer for both of these cases, ie. keep the current behavior for the second case, and change the behavior in the first to not introduce a new - if the user presses Return twice, ie. terminate the list.