Code folding does not work for Python or R code cells

[jmcphers]

Positron Version:

2024.04.0 build 1570

Steps to reproduce the issue:

Add a Python code cell to a .py file:

# %%
msg = "Hello World"
print(msg)

And/or an R code cell to a .R file:

#+
msg <- "Hello World"
print(msg)

What did you expect to happen?

These code cells should be foldable.

We have a folding provider which detects them (implemented here: https://github.com/posit-dev/positron/blob/main/extensions/positron-code-cells/src/folding.ts), but it has been temporarily disabled because enabling it turns off all other code folding in these scripts. Details here:

#2902

The best fix for this issue would be for the R and Python language packs to contribute their own folding providers (e.g. #18). The editor is smart enough to combine folding ranges from multiple providers.

Alternately, we could patch the editor so that it is able to merge built-in indentation based folding ranges with ranges supplied by an extension.

[kv9898]

I'm trying to include a fix to this in my PR: posit-dev/ark#615, in addition to foldable nested comment sections.

However, I'm not quite sure how the code cell should end?

[lionel-]

@kv9898 The code cells extend up to the next cell fence. See https://code.visualstudio.com/docs/python/jupyter-support-py

#+ cell a
"this"

"is"

"cell a"

#+ cell b
"now starts cell b until the end of the doc or next cell"

[kv9898]

@kv9898 The code cells extend up to the next cell fence. See https://code.visualstudio.com/docs/python/jupyter-support-py

#+ cell a
"this"

"is"

"cell a"

#+ cell b
"now starts cell b until the end of the doc or next cell"

Thank you @lionel- ! I have added support for R code cells in ark in posit-dev/ark#615.