Folding closed R code blocks from *bottom* of block fails in quarto documents

[JohnnyZoomis]

System details

RStudio Edition  : Desktop
RStudio Version : 2024.04.0+735
OS Version         : MacOS 14.4.1
R Version            : 4.4.0

Steps to reproduce the problem

1. Open a quarto document containing unfolded (open) R code blocks in the RStudio source pane. Here I used the File -> New File -> Quarto Document... menu commands to create the pristine quarto new document template.

2. Attempt to fold closed an unfolded (open) R code block by clicking on the flippy triangle at the bottom of the code block. In the two images, this was at line 16.

Describe the problem in detail

The text between the bottom of the current block and either the i) header of the next code block, or ii) the end of the file, is folded closed. See line 16 of second image. In this case, the folded text went to the header of the next code block (line 20).

Describe the behavior you expected

The current code block (between lines 14 to 16 inclusive) is folded closed.

This report is in response to this discussion

• I have read the guide for submitting good bug reports.
• I have installed the latest version of RStudio, and confirmed that the issue still persists.
• [] If I am reporting an RStudio crash, I have included a diagnostics report.
• I have done my best to include a minimal, self-contained set of instructions for consistently reproducing the issue.

[ronblum]

@JohnnyZoomis Thank you for bringing this over from the Community post!

Ref: #14640 and #14652.

[gtritchie]

I narrowed down when this bug was introduced. It was working correctly in build 2024.04.0-396, with commit 78087e9 from Feb 3, 2024, and broken in build 2024.04.0-426 with commit 15196de on Feb 8, 2024.

Unfortunately there were no successful builds between those two so there's a list of commits to consider.

The most likely candidate for this issue is the Ace upgrade: #14227