Running an R code cell causes the constant generation of new .vdoc._____.r files, which each start their own language server instance

[JackF774]

Bug description

When I run an R code cell in a Quarto file in VS studio, with R attached, a .vdoc..r is generated (whitespace varies each time, I think its a fingerprint of some kind), and the language server is started for the respective vdoc. However, once the R process is connected, a new .vdoc..r is generated in the same tmp-____ directory, and a new language server instance is opened for this vdoc, this process continues until I either use q() to close the connection to R, or the amount of open language severs / R for Windows terminal front-end processes uses up all memory on my device causing some process to fail and resulting in the process stopping. Although only after a large amount of R process error: read ECONNRESET messages.

Steps to reproduce

For me, starting from a new empty directory under my ~ directory, I create the folder in VS studio, then I make a .qmd file, I write a simple R code cell, containing either nothing or just a simple print process. Then if R isn't already attached, it attaches and doesn't run the code. After that, either on second run or first, or seemingly just after some time, constant new vdocs are generated and language servers are opened for them.
I have a recording from VS studio developer tools if needed.

Actual behavior

Code in R cell may or may not successfully run, and new language server instances are constantly generated until a crash or manual detachment of R. Also some temporary files from the process remain in the Temp directory.

Expected behavior

Only one instance of language server is opened, or existing one is used, instead of new ones being opened, presumably existing .vdoc is used as well?

Your environment

IDE: VS code
Version: 1.111.0 (user setup)
Commit: ce099c1ed25d9eb3076c11e4a280f3eb52b4fbeb
Date: 2026-03-06T23:06:10Z
Electron: 39.6.0
ElectronBuildId: 13330601
Chromium: 142.0.7444.265
Node.js: 22.22.0
V8: 14.2.231.22-electron.0
OS: Windows_NT x64 10.0.26200 (Windows 11)

Quarto v1.9.35

Quarto VScode extension v1.130.0

ReditorSupport (R extension for VS code) v2.8.7

R v4.5.2 (RStudio 2025.09.2+418 "Cucumberleaf Sunflower" Release (12f6d5e22720bd78dbd926bb344efe12d0dce83d, 2025-10-20) for windows
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) RStudio/2025.09.2+418 Chrome/138.0.7204.251 Electron/37.6.1 Safari/537.36, Quarto 1.9.35 (C:/Users/[user_name]/AppData/Local/Programs/Quarto/bin/quarto.exe))

Languageserver v0.3.17

[juliasilge]

Thank you for this report! Can you install v1.129.0 of the extension and see if you observe the same problem?

cc @DavisVaughan for visibility (we may need to change our per-cell virtual doc handling to account for this behavior in VS Code)

[JackF774]

I believe I have down graded quarto to 1.129.0, and the glitch still seems to occur. It seemed to briefly stop after end tasking about 10 or so R terminal for Windows, but then after about half a minute or so the glitch reoccurred.

[JackF774]

I also want to mention that this glitch doesn't happen if I dock R and then run the same code through the R interactive terminal, this glitch only occurs with running R code cells in qmd files.

[DavisVaughan]

Can you please provide your video you mentioned?

[JackF774]

The recording was using the VS studio developer tools recorder, so the file is in .js format, for lighthouse.
The exporting process wasn't working so I manually pasted this in. So the recording may not work.

Recording 3_17_2026 at 6_42_03 PM.js

[juliasilge]

If it's not new to v1.130.0 then likely it's not about the change we made that increased the number of vdoc files, which is like a good news / bad news kind of situation!

I'll give a bit more background here. The virtual doc files with the filenames you are observe are what powers Quarto's ability to give you language-specific features in your code cells, even though the file itself isn't an .R file. There are little temporary .R files that get created when you need to do something that requires language smarts. This is by design.

Quarto and the Quarto extension do not control the R LSP very much when you're using the ReditorSupport extension, except to request things from the LSP. I think you might have better luck asking this question on one of these two repos:

• https://github.com/REditorSupport/vscode-R
• https://github.com/REditorSupport/languageserver

We are very happy to consider changes here in the Quarto extension, but nothing here controls details of the R language server in this situation.

[JackF774]

Okay, thank you very much for all the help!
I've found that Positron doesn't encounter this issue in the event that anyone else has this problem.

[bfrank5]

Hey @JackF774

I ran into a similar problem with language servers spawning whenever I hovered over a quarto code block. It seems rolling back to vscode-R 2.8.6 worked for me per:

REditorSupport/vscode-R#1107 (comment)