This is to avoid partial matching with option like code_folding = FALSE
Found in distill while it was warning for non empty chunk content while using
```{r, child="mychild.Rmd"}
Try this without this PR to get the warning
````markdown
---
title: "reprex"
---
```{r}
knitr::opts_chunk$set(code_folding = FALSE)
Warning message:
In call_block(block) :
The chunk 'unnamed-chunk-2' has the 'child' option, and this code chunk must be empty. Its code will be ignored.
This PR makes sure that `params[['code']]` does not do partial matching with `params$code`
it creates an issue with distill because `code_fold = FALSE` is an option used in the distill format,.
This is to avoid partial matching with option like
code_folding = FALSEFound in distill while it was warning for non empty chunk content while using
Warning message: In call_block(block) : The chunk 'unnamed-chunk-2' has the 'child' option, and this code chunk must be empty. Its code will be ignored.