raw_attribute in header-includes

[rstub]

With rmarkdown version 1.18 the one can no longer use the raw_attribute extension when specifying a header-includes:

---
output: 
  pdf_document:
    keep_tex: yes
header-includes:
- |
  ```{=latex}
  \newcommand{\foobar}[1]{Foo#1Bar}
  ```    
---

```{=latex}
\foobar{Baz}
```

The ccontent of header-includes is copied verbatim to the TeX file which leads to a

! LaTeX Error: Missing \begin{document}.

It works when one uses the more conventional

header-includes:
- \newcommand{\foobar}[1]{Foo#1Bar}

However, the pandoc manual actually advertises the use of raw-headers in the meta data block.

Note: This is motivated by trying to answer https://stackoverflow.com/questions/59245638/latex-error-environment-threeparttable-undefined. It seems the papaja package uses raw-headers.

xfun::session_info('rmarkdown')
#> R version 3.6.1 (2019-07-05)
#> Platform: x86_64-pc-linux-gnu (64-bit)
#> Running under: Debian GNU/Linux bullseye/sid
#> 
#> Locale:
#>   LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C              
#>   LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8    
#>   LC_MONETARY=en_US.UTF-8    LC_MESSAGES=en_US.UTF-8   
#>   LC_PAPER=en_US.UTF-8       LC_NAME=C                 
#>   LC_ADDRESS=C               LC_TELEPHONE=C            
#>   LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C       
#> 
#> Package version:
#>   base64enc_0.1.3  digest_0.6.23    evaluate_0.14    glue_1.3.1      
#>   graphics_3.6.1   grDevices_3.6.1  highr_0.8        htmltools_0.4.0 
#>   jsonlite_1.6     knitr_1.26       magrittr_1.5     markdown_1.1    
#>   methods_3.6.1    mime_0.7         Rcpp_1.0.3       rlang_0.4.2     
#>   rmarkdown_1.18.5 stats_3.6.1      stringi_1.4.3    stringr_1.4.0   
#>   tinytex_0.17     tools_3.6.1      utils_3.6.1      xfun_0.11       
#>   yaml_2.2.0      
#> 
#> Pandoc version: 2.5

^{Created on 2019-12-09 by the reprex package (v0.3.0)}

---

By filing an issue to this repo, I promise that

• I have fully read the issue guide at https://yihui.org/issue/.
• I have provided the necessary information about my issue.
  • If I'm asking a question, I have already asked it on Stack Overflow or RStudio Community, waited for at least 24 hours, and included a link to my question there.
  • If I'm filing a bug report, I have included a minimal, self-contained, and reproducible example, and have also included xfun::session_info('rmarkdown'). I have upgraded all my packages to their latest versions (e.g., R, RStudio, and R packages), and also tried the development version: remotes::install_github('rstudio/rmarkdown').
  • If I have posted the same issue elsewhere, I have also mentioned it in this issue.
• I have learned the Github Markdown syntax, and formatted my issue correctly.

I understand that my issue may be closed if I don't fulfill my promises.

[cderv]

I think this relates to the change in 5499ec6 to fix #1359 regarding how header-includes is processed.
it seems with this change, we loose the raw-attribute feature for header-includes...
Indeed papaja is using raw attributes in headers
https://github.com/crsh/papaja/blob/29e6cb0437f96d571943bdd27df2eb18b6a50e47/R/apa6_formats.R#L506

papaja could also adapt to the new rmarkdown header processing as header-includes is now processed as verbatim by rmarkdown but I am not sure it is a good idea to override pandoc feature through rmarkdown. here header-includes yaml field is no longer processed by pandoc, but process by rmarkdown to be included as command line argument instead.

not sure what is the best choices here... 🤔

If I may @crsh, I add you to this discussion as you are the author of papaja and also the one who opend issue #1359 in the first place.

[yihui]

I became aware of this problem while working on another issue (rstudio/rticles#257) last week. I think I'm in a dilemma now. Comparing this issue with #1359, I feel the latter is worse and harder to fix, so I tend to say that we'll have to drop the support for raw blocks in header-includes.

I'll think more about it. Thanks for the report!

[yihui]

I just pushed a fix for this problem (by removing ```{=latex} before writing the header content into a file). Thanks for the report!

[github-actions]

This old thread has been automatically locked. If you think you have found something related to this, please open a new issue by following the issue guide (https://yihui.org/issue/), and link to this old issue if necessary.