Can't compile a Quarto document in Positron

[Cidre-Gesplan]

Hello! I am experiencing an error when I try to compile a Quarto document in Positron.

Error in R:

---
title: "My test"
---

Testing Quarto with R.


```{r}
3 + 4
```

PS C:\Users\User\Downloads\test-quarto> quarto preview c:/Users/User/Downloads/test-quarto/testing.qmd --no-browser --no-watch-inputs
Error in dir.exists(x) : file name conversion problem -- name too long?
Calls: ... lapply -> FUN -> dir_exists -> -> dir.exists
Execution halted
PS C:\Users\User\Downloads\test-quarto>

Error in Python:

---
title: "My test"
jupyter: python3
---

Testing Quarto with Python.


```{python}
3 + 4
```

PS C:\Users\User\Downloads\test-quarto> quarto preview c:/Users/User/Downloads/test-quarto/testing.qmd --no-browser --no-watch-inputs
ERROR: El sistema no tiene acceso al archivo. (os error 1920): stat 'C:\Users\User\AppData\Local\Microsoft\WindowsApps\python.exe'

Stack trace:
at Object.statSync (ext:deno_fs/30_fs.js:425:3)
at existsSync (file:///C:/Users/User/AppData/Local/Programs/Quarto/bin/quarto.js:1988:27)
at getQuartoJupyterCapabilities (file:///C:/Users/User/AppData/Local/Programs/Quarto/bin/quarto.js:30756:13)
at eventLoopTick (ext:core/01_core.js:175:7)
at async jupyterCapabilities (file:///C:/Users/User/AppData/Local/Programs/Quarto/bin/quarto.js:30671:28)
at async pythonExec (file:///C:/Users/User/AppData/Local/Programs/Quarto/bin/quarto.js:30853:18)
at async Object.execute (file:///C:/Users/User/AppData/Local/Programs/Quarto/bin/quarto.js:40231:29)
at async renderExecute (file:///C:/Users/User/AppData/Local/Programs/Quarto/bin/quarto.js:85568:27)
at async renderFileInternal (file:///C:/Users/User/AppData/Local/Programs/Quarto/bin/quarto.js:85736:43)
at async renderFiles (file:///C:/Users/User/AppData/Local/Programs/Quarto/bin/quarto.js:85604:17)
PS C:\Users\User\Downloads\test-quarto>

I am using latest Positron release (but it also happened with the previous one):

Positron: 2025.03.0 build 116
Positron SHA: 7f0f938
Code OSS: 1.96.0
Arch: x64

And Quarto v1.6.42, although I happened also with v1.6.40.

However, when I render the document in RStudio it works perfectly. Does anyone have any idea why is this happening?

[juliasilge]

What happens if you try to render one of these files from the command line? For example, from your regular (not in Positron) shell in the same directory with the file:

quarto render testing.qmd

What happens if you try the same thing in the Positron terminal pane?

[Cidre-Gesplan]

Hello @juliasilge.

I update the errors after installing python 3, which wasn't installed in the machine where I got the errors.

When I use Positron preview button:

R:

It doesn't work.

PS C:\Users\User\Downloads\test-quarto> quarto preview c:/Users/User/Downloads/test-quarto/test-r.qmd --no-browser --no-watch-inputs
Error in dir.exists(x) : file name conversion problem -- name too long?
Calls: <Anonymous> ... lapply -> FUN -> dir_exists -> <Anonymous> -> dir.exists
Execution halted

Python:

It doesn't work.

PS C:\Users\User\Downloads\test-quarto> quarto preview c:/Users/User/Downloads/test-quarto/test-py.qmd --no-browser --no-watch-inputs

Starting python3 kernel...Done

Executing 'test-py.quarto_ipynb'
  Cell 1/1: ''...Done

pandoc 
  to: html
  output-file: test-py.html
  standalone: true
  section-divs: true
  html-math-method: mathjax
  wrap: none
  default-image-extension: png
  
metadata
  document-css: false
  link-citations: true
  date-format: long
  lang: en
  title: My test
  jupyter: python3
  
Output created: _site\test-py.html

Preparing to preview
[1/1] test-r.qmd
Error in dir.exists(x) : file name conversion problem -- name too long?
Calls: <Anonymous> ... lapply -> FUN -> dir_exists -> <Anonymous> -> dir.exists
Execution halted

When I use the command line:

R:

It doesn't work.

(base) C:\Users\User\Downloads\test-quarto>quarto render test-r.qmd
Error en dir.exists(x):
  problema de conversión de nombre de archivo -- ¿nombre del archivo demasiado largo?
Calls: <Anonymous> ... lapply -> FUN -> dir_exists -> <Anonymous> -> dir.exists
Ejecución interrumpida

Python:

It works.

(base) C:\Users\User>cd C:\Users\User\Downloads\test-quarto
(base) C:\Users\User\Downloads\test-quarto>quarto render test-py.qmd

Starting python3 kernel...Done

Executing 'test-py.quarto_ipynb'
  Cell 1/1: ''...Done

pandoc
  to: html
  output-file: test-py.html
  standalone: true
  section-divs: true
  html-math-method: mathjax
  wrap: none
  default-image-extension: png

metadata
  document-css: false
  link-citations: true
  date-format: long
  lang: en
  title: My test
  jupyter: python3

Output created: _site\test-py.html

So now the error that I get is always the same one.

[juliasilge]

This looks very similar to the problems being reported in quarto-dev/quarto-cli#12248. Can you open a new Quarto discussion at https://github.com/quarto-dev/quarto-cli/discussions and link to that other discussion, to see what the Quarto team recommends? Since you see the same error with R both when using Positron and when rendering from the command line, it sounds like the problem is with Quarto and unlikely to be due to Positron.