output file name conflict when two formats targets same extension (like html and revealjs)

[royfrancis]

Bug description

When defining both html and revealjs formats in the config (_quarto.yml), if format is not defined in individual qmd files, it gives this error:

ERROR: NotFound: No such file or directory (os error 2), rename '/home/user/Desktop/test/report.html' -> '/home/user/Desktop/test/_site/report.html'

To reproduce, create three files:

_quarto.yml

project:
  type: website

website:
  title: "Test"

format:
  html:
    theme: "flatly"
  revealjs:
    theme: "beige"

presentation.qmd

---
title: "Presentation"
format: revealjs
---

## Slide 1

This is a presentation

## Slide 2

More contents here

report.qmd

---
title: "Report"
---

## Heading 1

This is a report

Then run quarto render. Adding format: html to report.qmd fixes this issue.

It took me a while to troubleshoot as the error message was not helpful.

🢒  quarto --version
1.2.1

🢒  lsb_release -a
No LSB modules are available.
Distributor ID:	Zorin
Description:	Zorin OS 16.2
Release:	16
Codename:	focal

Checklist

• Please include a minimal, fully reproducible example in a single .qmd file? Please provide the whole file rather than the snippet you believe is causing the issue.
• Please format your issue so it is easier for us to read the bug report.
• Please document the RStudio IDE version you're running (if applicable), by providing the value displayed in the "About RStudio" main menu dialog?
• Please document the operating system you're running. If on Linux, please provide the specific distribution.

[cscheid]

It would be ideal for quarto to issue a warning in this sort of scenario. But what's happening here is that both of your html and revealjs formats are rendering to the same output file. When you write in your _quarto.yml

format:
  html:
    theme: "flatly"
  revealjs:
    theme: "beige"

you're effectively telling quarto: "render these two formats when I don't specify otherwise". So quarto will attempt to render a revealjs presentation and a webpage for every .qmd file. This confuses quarto, because they both generate .html files.

Things work when you specify a single format (like format: html or format: revealjs) because we take those to mean "render only this specific format".

As a result, when you're using this particular style in _quarto.yml, you really do need to specify a particular format at every .qmd file. We'd like to do better here and warn that multiple outputs are being generated (and so quarto will step on its own toes along the way), but it's a generally hard problem because we don't control all possible filenames.

In the end, I agree this is a bug, but it'll be very hard for us to fix it in a short to medium timeframe.

[chaz-clark]

I get this error when rendering a qmd file.

Mac Terminal out of error:

Preview service running (5981)
ERROR: NotFound: No such file or directory (os error 2)

Stack trace:
    at opRun (ext:runtime/40_process.js:46:14)
    at Object.run (ext:runtime/40_process.js:132:15)
    at externalPreviewServer (file:///Applications/quarto/bin/quarto.js:96055:26)
    at serveProject (file:///Applications/quarto/bin/quarto.js:95998:240)
    at eventLoopTick (ext:core/01_core.js:181:11)
    at async Command.fn (file:///Applications/quarto/bin/quarto.js:96565:9)
    at async Command.execute (file:///Applications/quarto/bin/quarto.js:8111:13)
    at async quarto (file:///Applications/quarto/bin/quarto.js:111534:5)
    at async file:///Applications/quarto/bin/quarto.js:111552:9

Yamal code at top of qmd file:

format:
  html:
    self-contained: true
    page-layout: full
    title-block-banner: true
    toc: true
    toc-depth: 3
    toc-location: body
    number-sections: false
    html-math-method: katex
    code-copy: true
    code-fold: true
    code-line-numbers: true
    code-summary: "Show the code"
    code-overflow: wrap
    code-tools:
        source: false
        toggle: true
        caption: See code
---

Note: HTML file still produces and seems accurate. I tested both the current and the pre-release quarto 1.4.3 and i get the issue in both

Quarto Check output

M2 Mac Book Pro
Quarto 1.4.386
[✓] Checking versions of quarto binary dependencies...
      Pandoc version 3.1.8: OK
      Dart Sass version 1.55.0: OK
      Deno version 1.33.4: OK
[✓] Checking versions of quarto dependencies......OK
[✓] Checking Quarto installation......OK
      Version: 1.4.386
      Path: /Applications/quarto/bin

[✓] Checking tools....................OK
      TinyTeX: (not installed)
      Chromium: (not installed)

[✓] Checking LaTeX....................OK
      Tex:  (not detected)

[✓] Checking basic markdown render....OK

[✓] Checking Python 3 installation....OK
      Version: 3.11.5
      Path: /usr/local/bin/python3
      Jupyter: 5.3.1
      Kernels: python3

(/) Checking Jupyter engine render....0.00s - Debugger warning: It seems that frozen modules are being used, which may
0.00s - make the debugger miss breakpoints. Please pass -Xfrozen_modules=off
0.00s - to python to disable frozen modules.
0.00s - Note: Debugging will proceed. Set PYDEVD_DISABLE_FILE_VALIDATION=1 to disable this validation.
(/) Checking Jupyter engine render....0.00s - Debugger warning: It seems that frozen modules are being used, which may
0.00s - make the debugger miss breakpoints. Please pass -Xfrozen_modules=off
0.00s - to python to disable frozen modules.
0.00s - Note: Debugging will proceed. Set PYDEVD_DISABLE_FILE_VALIDATION=1 to disable this validation.
[✓] Checking Jupyter engine render....OK

[✓] Checking R installation...........OK
      Version: 4.3.1
      Path: /Library/Frameworks/R.framework/Resources
      LibPaths:
        - /Library/Frameworks/R.framework/Versions/4.3-arm64/Resources/library
      knitr: 1.43
      rmarkdown: (None)

      The rmarkdown package is not available in this R installation.
      Install with install.packages("rmarkdown")

[mcanouil]

@chaz-clark please format your post properly for it to be legible, i.e., use code blocks for code and outputs and use more backticks to enclose a code with code blocks.

You can share a Quarto document using the following syntax, i.e., using more backticks than you have in your document (usually four ````).

````qmd
---
title: "Reproducible Quarto Document"
format: html
---

This is a reproducible Quarto document using `format: html`.
It is written in Markdown and contains embedded R code.
When you run the code, it will produce a plot.

```{r}
plot(cars)
```

The end.
````