Interaction between pkdown and `\AND` in JSS articles

[nbenn]

---

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---

When creating a package website using pkgdown for a package that contains a JSS vignette which has authors arranged using \AND, the following issue comes up:

First a minimal package where everything works as expected:

usethis::create_package("rticles398")
usethis::use_mit_license()
rmarkdown::draft("vignettes.Rmd", template = "jss", package = "rticles",
                 edit = FALSE)

rmd <- readLines("vignettes/vignettes.Rmd")
ind <- grep("---", rmd)[2L]
rmd <- c(
   rmd[seq_len(ind - 1L)],
   "pkgdown:",
   "  as_is: true",
   "  extension: pdf",
   "vignette: >",
   "  %\\VignetteIndexEntry{A Capitalized Title}",
   "  %\\VignetteEngine{knitr::rmarkdown}",
   "  %\\VignetteEncoding{UTF-8}",
   rmd[seq.int(ind, length(rmd))]
)
write(rmd, file = "vignettes/vignettes.Rmd")

usethis:::use_dependency("knitr", "Suggests")
usethis:::use_dependency("rmarkdown", "Suggests")
usethis:::use_dependency("rticles", "Suggests")
usethis:::use_description_field("VignetteBuilder", "knitr", overwrite = TRUE)
usethis:::use_git_ignore("inst/doc")

devtools::build_vignettes()
# --> all fine
pkgdown::build_site()
# --> all fine

If, however the affiliation containing the \AND also contains an address, as

rmd <- readLines("vignettes/vignettes.Rmd")
ind <- grep("\\AND", rmd)[1L]
rmd <- c(
   rmd[seq_len(ind + 1L)],
   "    address: |",
   "      | First line",
   "      | Second line",
   rmd[seq.int(ind + 2L, length(rmd))]
)
write(rmd, file = "vignettes/vignettes.Rmd")

devtools::build_vignettes()
# --> all fine
pkgdown::build_site()
#> Error : Failed to render RMarkdown
#> * ! Undefined control sequence.
#> * \@Address ...~\\ Second Author\\ Affiliation \AND
#> *                                                   \\ First line\\ Second lin...
#> * l.124 \end{document}
#> *
#> * Error : LaTeX failed to compile /some/dir/rticles398/docs/articles/vignettes.tex. See https://yihui.org/tinytex/r/#debugging for debugging tips. See vignettes.log for more info.

There is a fix for this: If an affilliation2 is added in addition to the offending affiliation, which does not contain the the \AND, the problem goes away.

1. Is this intentional?
2. If so, I feel adding a remark somewhere, outlining the fix above, would be helpful, as it took me quite some time to get there.

---

R version 4.0.4 (2021-02-15)
Platform: x86_64-apple-darwin17.0 (64-bit)
Running under: macOS Big Sur 10.16

Locale: en_US.UTF-8 / en_US.UTF-8 / en_US.UTF-8 / C / en_US.UTF-8 / en_US.UTF-8

Package version:
  digest_0.6.27   evaluate_0.14   glue_1.4.2      graphics_4.0.4
  grDevices_4.0.4 highr_0.9       htmltools_0.4.0 jsonlite_1.7.2
  knitr_1.33      magrittr_2.0.1  markdown_1.1    methods_4.0.4
  mime_0.10       Rcpp_1.0.6      rlang_0.4.11    rmarkdown_2.6
  rticles_0.19    stats_4.0.4     stringi_1.5.3   stringr_1.4.0
  tinytex_0.31    tools_4.0.4     utils_4.0.4     xfun_0.22
  yaml_2.2.1

[cderv]

Is this happening only with pkgdown or can you make a reproducible example with rmarkdown and rticles only with an Rmd file built using rmarkdown::render() ?

If so, that would be easier for me to understand and see the underlying issue.

Thanks.

[nbenn]

I'm sorry, but I don't see how to make the above reproducible example more reproducible. I do say that devtools::build_vignettes() succeeds where pkgdown::build_articles() fails, so the problem is not with rmarkdown::render() (which can be verified with the above example) but is somehow an interaction between pkgdown::build_articles() and specifics of this type of vignette. If you feel that this is more an issue with pkdgown than with rticles, I apologize and you can go ahead and close again.

[cderv]

Thanks for you precision. I missed the fact that this works fine with rmarkdown::render() but fail with the package bundling usage. It feels like this may be an issue with how pkgdown is rendering the vignette.

With an issue like this one, it requires digging and making the reproducible example a minimal reproducible example which is always difficult. For now, this could be in one of the layer involved. (pkgdown, rmarkdown, rticles, the LaTeX template inside rticles, ...)

As this works with rmarkdown::render() or devtools::build_vignettes() and fails only with pkgdown, I would say the issue is there but I don't have a clue why.

As I said, this requires digging but it does not feel like a rticles issue directly. If we need to make some adaptation for pkgdown to work, then we'll happily do it.

If not already, it could be interesting to have this reported in pkgdown also to have more help from them to solve this.

I'll leave that open, but we'll need some help looking into this.