unevaluated chunks with labelled tables crash a lua filter

[aghaynes]

Description

When chunks are run dynamically and depend on some condition earlier in the code, it might be necessary to evaluate a chunk or not. In testing I noticed that labelled chunks seem to cause problems with a lua filter...

---
title: "Untitled"
format: html
execute:
  echo: false
---

```{r}
#| eval: true
#| label: tbl-t1
#| tbl-cap: dgdfgh
mtcars |> head() |> knitr::kable()
```

```{r}
#| eval: false
#| label: tbl-t2
#| tbl-cap: hggfh
mtcars |> head() |> knitr::kable()
```

```{r}
#| eval: true
#| label: tbl-t3
#| tbl-cap: fghfgj
mtcars |> head() |> knitr::kable()
```

Error running filter C:/PROGRA~1/Quarto/share/filters/main.lua:
C:/PROGRA~1/Quarto/share/filters/main.lua:17510: attempt to index a nil value (field 'content')
stack traceback:
	C:/PROGRA~1/Quarto/share/filters/main.lua:2925: in local 'filter_fn'
	C:/PROGRA~1/Quarto/share/filters/main.lua:613: in function <C:/PROGRA~1/Quarto/share/filters/main.lua:603>
	(...tail calls...)
	[C]: in ?
	[C]: in method 'walk'
	C:/PROGRA~1/Quarto/share/filters/main.lua:535: in function <C:/PROGRA~1/Quarto/share/filters/main.lua:524>
	(...tail calls...)
	C:/PROGRA~1/Quarto/share/filters/main.lua:1312: in local 'callback'
	C:/PROGRA~1/Quarto/share/filters/main.lua:1330: in upvalue 'run_emulated_filter_chain'
	C:/PROGRA~1/Quarto/share/filters/main.lua:1366: in function <C:/PROGRA~1/Quarto/share/filters/main.lua:1363>
stack traceback:
	C:/PROGRA~1/Quarto/share/filters/main.lua:535: in function <C:/PROGRA~1/Quarto/share/filters/main.lua:524>
	(...tail calls...)
	C:/PROGRA~1/Quarto/share/filters/main.lua:1312: in local 'callback'
	C:/PROGRA~1/Quarto/share/filters/main.lua:1330: in upvalue 'run_emulated_filter_chain'
	C:/PROGRA~1/Quarto/share/filters/main.lua:1366: in function <C:/PROGRA~1/Quarto/share/filters/main.lua:1363>

[aghaynes]

update: this only seems to happen with captions...

[cscheid]

Specifically, this happens when the cell includes indicators of a crossreferenceable element (label: tbl-* and tbl-cap: ...), but eval: false causes the cell to not produce output.

It's a bug.

[mcanouil]

Thanks for the report being tracked in:

• unevaluated chunks with labelled tables crash a lua filter #9863

(FYI, it's also in the "Events" log on the right of this discussion on a "desktop" view)