Remark: Nested list item becomes single paragraph when indenting >=4 spaces

Created on 19 Aug 2020 · 5Comments · Source: remarkjs/remark

Subject of the issue

It seems like if the 4-space indented list item is followed by an unindented text block, the parser would recognize all 3 lines into a single paragraph within the first list item. This doesn't seem to happen without an unindented text block after, nor with 2 or 3 spaces of indentation. With CommonMark, it seems that this behavior only happens when indenting >=6 spaces.

Your environment

OS: Windows 10
Packages: remark-parse 8.0.3
Env: Chrome 84.0.4147.125

Steps to reproduce

Sample: (notice there are exactly 4 spaces in the second list item, the same happens with a tab character)

- Test
    - Test
Test

remark

CommonMark dingus

Observation

Interestingly, when the indentation is done with 2 or 3 spaces, the parser correctly recognize the list item. Only when 4 or more spaces does remark fail to parse the indented list item.

With CommonMark, it seems like the required number of spaces to produce a similar result is 6 spaces instead of 4.

Debugging

I've put in a few hours stepping through the code. It's a bit tedious and difficult to understand, but it would seem that the normalListItem function eats up the - at the beginning of the first line, causing the difference in indentation to be 2 characters greater, which may be causing the symptom observed.

Unfortunately, with my limited experience, I am unsure how to continue with debugging or coming up with a fix.

Additional Information

This behavior is similar to https://github.com/remarkjs/remark/issues/315 so they might be related.

remark-parse ⛵️ statureleased 🐛 typbug

Source

lishid

All 5 comments

Heya, just wanted to give an update about micromark, it’s sort-of a new motor that we’ll soon use in remark to parse markdown. It’s not yet 100% ready but will be relatively soon. The good news is, it fixes this issue! (P.S. see this twitter thread for some more info!)