Add info about figures in article about precomputing vignettes

[Aariq]

The article about precomputing vignettes has a caveat that if your vignette includes figures, you must take care to save them to the vignettes/folder. It would be nice to have an example of how to do that. I was thinking this might do the trick:

knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>",
  fig.path = "vignettes/"
)

But the figure generated in the pre-compute step doesn't get moved to doc/ by build_vignettes() or to docs/articles/ by pkgdown::build_site() and the images don't show up in the rendered HTML. Do I need to just manually (or with a script) move the figures to the correct spot(s)?

[Aariq]

Ah, I think I figured out that the figures need to be in vignettes/figure/ for this to work. A precompile.R script like so does the trick:

knitr::knit("vignettes/fluxnet.Rmd.source", output = "vignettes/fluxnet.Rmd")
# Move generated figures to the correct place
fs::dir_copy(path = "figure", new_path = "vignettes/figure")
fs::dir_delete("figure")

[maelle]

Oh I see the example (the eia package) itself changed!
Would you like to make a PR to link (permalink) to your package instead?
The original script actually indicated a manual step https://github.com/ropensci/eia/blob/95cd1e10ebda4143fd4fe24cf5836b10fa757a31/vignettes/precompile.R#L2

[Aariq]

Can do!

[maelle]

Thanks a ton!