vignette build fail: knitr unable to interprete Rmarkdown

Question

I have been building vignettes with knitr for several months but about 10 days ago, this message appeared after using R CMD build or devtools::build():

It seems you should call rmarkdown::render() instead of knitr::knit2html() because Release.Rmd appears to be an R Markdown v2 document.

I thought it would be linked to text inside the vignette so I reduced it to a minimal reproducible example:

title: "Release"
output:
  html_vignette
vignette: >
  %\VignetteIndexEntry{Release}
  %\VignetteEngine{knitr::knitr}
  %\VignetteEncoding{UTF-8}
---

Release 

Force evaluation

I tried to force the evaluation of the Rmarkdown adding:

params:
  force_v1: TRUE

Change vignette builder

I also tried to replace the VignetteEngine by rmarkdown::render and editing the VignetteBuilder in the Description file. This skips the vignette building as rmarkdowndoes not seem to be a known vignette builder.

Question:

Is there a way to solve this using knitr or alternatively by building vignettes with rmarkdown?

Additional information

I tried to build the package both on Windows and Centos, with different versions. Failing build information can also be found here

Answer 1

I use these settings, and they work:

output:  rmarkdown::html_vignette
vignette: >
  %\VignetteEngine{knitr::rmarkdown}
  %\VignetteIndexEntry{the title}