Importing code chunks from an external R script

[arnaudgallou]

Is there a way to import chunks of a R script in a .qmd document? I have tried using knitr::read_chunk() (see example below or here) but I didn't manage to make it work in Quarto.

read_chunk.R:

x <- "blah"

# ---- foo ----

ggplot() +
  geom_segment(aes(x = 0, xend = 1, y = 0, yend = 1)) +
  lims(x = c(0, 1), y = c(0, 1)) +
  theme(
    text = element_text(size = 20),
    axis.ticks = element_blank(),
    axis.text = element_blank()
  ) +
  ggtitle("foo")

# ---- bar ----

ggplot() +
  geom_segment(aes(x = 1, xend = 0, y = 1, yend = 0)) +
  lims(x = c(0, 1), y = c(0, 1)) +
  theme(
    text = element_text(size = 20),
    axis.ticks = element_blank(),
    axis.text = element_blank()
  ) +
  ggtitle("bar")

read_chunk.qmd:

---
title: Importing code chunk using `knitr::read_chunk()`
editor_options:
  markdown: 
    wrap: sentence
execute:
  echo: false
  warning: false
---

```{r}
library(ggplot2)
knitr::read_chunk("read_chunk.R")
```

```{r foo}
```

Did I do something wrong in my example? If not, is there a similar tool or feature available in Quarto to do that?

Please note that converting the .qmd to .Rmd will correctly import and render the foo chunk.

[jjallaire]

@yihui I've confirmed that the call to read_chunk() doesn't seem to work in quarto. Could this be due to some of our hooks? Perhaps there is a line or two of code we need to add in order to respect cells populated via labels from read_chunk() ?

[yihui]

I don't know and don't have time to debug it until I come back from vacation. You can check if knitr::knit_code$get() contains the code after calling read_chunk(). Then figure out why the code is not applied to the chunk.

[jjallaire]

I spent some time trying to figure out what was going on -- it seems like perhaps in the case of quarto the code option is explicitly set somehow (although I couldn't see where this might be happening in either quarto or knitr::parse_block). If code is in fact set then this will override any code read via read_chunk()

[arnaudgallou]

Thank you for looking into the problem. I will use a different approach for now. I hope a solution that works will be implemented in the future.

[jjallaire]

Thanks again for reporting this, should be fixed here: a120c2a

[arnaudgallou]

Works like a charm. Thank you.

[cderv]

This was related to other issue (#1034) and now fixed in Quarto v0.9.499 and above, as mentioned above