Quarto vignette rendering fails on Windows due to invalid path concatenation (mixed drive paths)

[kv9898]

Description

When building a pkgdown site with Quarto vignettes on Windows, pkgdown::build_articles() fails due to an invalid path being passed to the Quarto CLI.

The error appears to be caused by incorrect concatenation of an absolute temporary path with a project-relative path, resulting in a malformed path like:

> pkgdown::build_articles(quiet = FALSE)
── Building articles ─────────────────────────────────────────────────────────────────────────────────────────
Reading vignettes/test.qmd
Running `quarto render`
ERROR: 文件名、目录名或卷标语法不正确。 (os error 123): stat 'E:\resultcheck\vignettes\C:\Users\Dianyi\AppData\Local\Temp\RtmpIbtb3w\pkgdown-quarto-acd4bda5188'

Stack trace:
    at Object.statSync (ext:deno_fs/30_fs.js:415:3)
    at ensureDirSync (file:///E:/quarto/bin/quarto.js:2466:27)
    at renderProject (file:///E:/quarto/bin/quarto.js:130462:5)
    at async _Command.actionHandler (file:///E:/quarto/bin/quarto.js:135810:24)
    at async _Command.execute (file:///E:/quarto/bin/quarto.js:95902:7)
    at async _Command.parseCommand (file:///E:/quarto/bin/quarto.js:95779:14)
    at async quarto4 (file:///E:/quarto/bin/quarto.js:183810:5)
    at async file:///E:/quarto/bin/quarto.js:183838:5
    at async file:///E:/quarto/bin/quarto.js:183693:14
    at async mainRunner (file:///E:/quarto/bin/quarto.js:183695:5)

Error in `quarto::quarto_render()`:
! Error running quarto CLI from R.
Caused by error in `quarto::quarto_render()`:
✖ Error returned by quarto CLI.
  -----------------------------
  ERROR: 文件名、目录名或卷标语法不正确。 (os error 123): stat
  'E:\resultcheck\vignettes\C:\Users\Dianyi\AppData\Local\Temp\RtmpIbtb3w\pkgdown-quarto-acd4bda5188'
  
  Stack trace:
  at Object.statSync (ext:deno_fs/30_fs.js:415:3)
  at ensureDirSync (file:///E:/quarto/bin/quarto.js:2466:27)
  at renderProject (file:///E:/quarto/bin/quarto.js:130462:5)
  at async _Command.actionHandler (file:///E:/quarto/bin/quarto.js:135810:24)
  at async _Command.execute (file:///E:/quarto/bin/quarto.js:95902:7)
  at async _Command.parseCommand (file:///E:/quarto/bin/quarto.js:95779:14)
  at async quarto4 (file:///E:/quarto/bin/quarto.js:183810:5)
  at async file:///E:/quarto/bin/quarto.js:183838:5
  at async file:///E:/quarto/bin/quarto.js:183693:14
  at async mainRunner (file:///E:/quarto/bin/quarto.js:183695:5)
  
Caused by error:
! System command 'quarto.exe' failed

The same vignette renders correctly with:

quarto::quarto_render("vignettes/test.qmd")

[roliveros-ramos]

I can confirm I was hitting the same issue on Windows when running pkgdown::build_site() with Quarto articles.

In my case, the failure involved a malformed path where the package/vignettes path was being concatenated with an absolute temporary directory path, leading to an invalid path of the form:

R:\...\vignettes\C:\Users\...\Temp\...

My setup includes a mixed vignettes/articles directory with both .Rmd and .qmd files, plus a _quarto.yml restricting Quarto rendering to *.qmd, following the documented pkgdown configuration.

After installing pkgdown from the PR commit proposed in #2983, the problem was resolved and pkgdown::build_site() completed successfully.

So this PR fixes the issue for me, and I support getting a solution for this into pkgdown.