Officedown: `rpptx_document` produces an unopenable pptx file

[CLRafaelR]

@davidgohel

When I knit an Rmd file with officedown::rpptx_document, the function produces an unopenable pptx file with the following error message:

PowerPoint found a problem with content in xxxx.pptx.
PowerPoint can attempt to repair the presentation.

I confirmed that the contents of the Rmd are knittable with, for eaxample, bookdown::powerpoint_presentation2. Therefore, I suspect some bugs might lie in officedown::rpptx_document.

MWE

---
title: "Untitled"
author: "CLRR"
date: "2020/6/20"
output: 
  officedown::rpptx_document:
    keep_md: TRUE
  bookdown::powerpoint_presentation2:
    keep_md: TRUE
  ---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = FALSE)
```

## R Markdown

This is an R Markdown presentation. Markdown is a simple formatting syntax for     authoring HTML, PDF, and MS Word documents. For more details on using R Markdown see     <http://rmarkdown.rstudio.com>.

When you click the **Knit** button a document will be generated that includes both     content as well as the output of any embedded R code chunks within the document.

## Slide with Bullets

- Bullet 1
- Bullet 2
- Bullet 3

## Slide with R Output

```{r cars, echo = TRUE}
summary(cars)
```

## Slide with Plot

```{r pressure}
plot(pressure)
```

Session Info

rmarkdown::pandoc_version()
[1] ‘2.9.2.1’

R version 4.0.0 (2020-04-24)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 10 x64 (build 18362)

Matrix products: default

locale:
[1] LC_COLLATE=Japanese_Japan.932  LC_CTYPE=Japanese_Japan.932        LC_MONETARY=Japanese_Japan.932 LC_NUMERIC=C                   LC_TIME=Japanese_Japan.    932    

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

loaded via a namespace (and not attached):
Rcpp_1.0.4.6      
packrat_0.5.0     
digest_0.6.25     
R6_2.4.1          
magrittr_1.5      
officedown_0.1.0  
evaluate_0.14     
zip_2.0.4         
gdtools_0.2.2     
rlang_0.4.6       
uuid_0.1-4        
xml2_1.3.2        
rmarkdown_2.2    
tools_4.0.0       
officer_0.3.11    
xfun_0.14         
yaml_2.2.1        
compiler_4.0.0    
systemfonts_0.2.3 r
vg_0.2.4         
memoise_1.1.0     
htmltools_0.4.0   
knitr_1.28

[davidgohel]

Thanks for reporting that.

It seems it only happens with R for Windows. I don't know yet where is the issue.

[mtkerbeR]

First of all:
Thanks for the awesome package - really great! A pleasure to work with/use it - especially in connection with flextable.

From my point of view, the problem on windows might be caused by the value of reference_doc.
While using the pptx-template in officer does not seem to work on windows (see below), the code works using the pandoc reference template:

---
title: "Untitled"
author: "CLRR"
date: "2020/6/20"

output: 
   officedown::rpptx_document:
     # not working:
     # reference_doc: C:/R/lib/officer/template/template.pptx
     # set reference_doc to standard pandoc layout:
     # system2(rmarkdown::pandoc_exec(), args = c("--print-default-data-file", "reference.pptx"), stdout = "C:/R/pandoc_layout.pptx")
     reference_doc: C:/R/pandoc_layout.pptx
     keep_md: TRUE

---


## R Markdown

Test

The choice of the template - using the officer-internal template instead of pandocs reference doc - might be triggered within the function officedown:::get_default_pandoc_data_file
see Enable usage of Pandoc-pptx-reference doc.

[CLRafaelR]

@mtkerbeR

The following command on R console which you suggested doesn't work:

> system2(rmarkdown::pandoc_exec(), args = c("--print-default-data-file", "reference.pptx"), stdout = "C:/R/pandoc_layout.pptx")
pandoc.exe: <stdout>: hPutBuf: invalid argument (Bad file descriptor)

Where should pandoc_layout.pptx exit innately? Or should I create a pptx file by myself instead? I don't have R directory under my C directory, i.e. there is no C:/R/. I have C:\Program Files\R, C:\Program Files\RStudio, C:\Users\my-user-name\AppData\Local\RStudio, C:\Users\my-user-name\AppData\Local\RStudio.

[CLRafaelR]

@davidgohel and @mtkerbeR

Now I succeeded to get a pptx file!

(1) I created pandoc_layout.pptx in a certain directory (C:/Users/my-user-name/Documents/R at this time) and

(2) ran the following code as @mtkerbeR suggested:

system2(rmarkdown::pandoc_exec(), args = c("--print-default-data-file", "reference.pptx"), stdout = "C:/Users/my-user-name/Documents/R/pandoc_layout.pptx")

(3) then I knitted a Rmd file with the option reference_doc: C:/Users/my-user-name/Documents/R/pandoc_layout.pptx in YAML.

[davidgohel]

Thanks

This is now fixed in the github version.

There were two issues, one with the windows missing .exe and another one about temporary file used as reference_doc. Thanks to @mtkerbeR for the help

[CLRafaelR]

I confirmed the github version's officedown::rpptx_document produces an openable file. This is brilliant!! I appreciate @davidgohel for the bug fix and @mtkerbeR for helpfull contributions!