Smart custom knit doesn't work when --- separator exists in Rmd #855
Description
When --- separator exists in Rmd file, the smart custom knit doesn't work; instead, it falls back to rmarkdown::render() default.
However, when --- is taken out, the custom knit works again.
This is critical because the --- separator is often used in presentation output.
Reproducible Examples
Example 1: With --- separator.
---
output: bookdown::gitbook
knit: bookdown::render_book
---
# Test
Para.
---
# Next
Example 2: Without --- separator.
---
output: bookdown::gitbook
knit: bookdown::render_book
---
# Test
Para.
# Next