Keyboard shortcuts for R assignment operators and pipe do not always work in reticulate `.qmd`

[ntluong95]

System details:

Positron and OS details:

Positron Version: 2025.04.0 (system setup) build 173
Code - OSS Version: 1.97.0
Commit: a66eb31
Date: 2025-03-24T02:57:55.373Z
Electron: 32.2.7
Chromium: 128.0.6613.186
Node.js: 20.18.1
V8: 12.8.374.38-electron.0
OS: Windows_NT x64 10.0.26120

Interpreter details:

Describe the issue:

The keyboard shortcuts Alt + - and Ctrl + Shift + M does not work in R cell if there are 3 python cells above

Steps to reproduce the issue:

1. Create a blank .qmd file
2. Add 3 python code chunks then a R code chunk. Try to use keyboard shortcut here

```{python}
a = 1
```

```{python}
b = 2
```

```{python}
c = 3
```

```{r}
x
```

Expected or desired behavior:

Work normally

Were there any error messages in the UI, Output panel, or Developer Tools console?

N/A

[timtmok]

Thanks for flagging this! We appreciate your help improving Positron!

I think this may be something the Quarto extension needs to support. The shortcut is enabled by asking it the document's language. I think it will need to provide a way to check the language of the current code cell. Let me check with the Quarto team on how to proceed with this.

[juliasilge]

This is a known limitation right now of our approach for identifying the language of a Quarto document. I worked on that in quarto-dev/quarto#608, and the approach leans on how the Quarto extension identifies the quarto.document.languageId for a document using the mainLanguage for the virtual documents it generates.

This request is related to #6684, which also requires something more like a quarto.cell.languageId (but kind of for the opposite reason, to not provide the keyboard shortcuts when we shouldn't).