Some parameter names are converted to TRUE or FALSE

[PuzzledFace]

Consider the YAML header

---
params:
  x: NA
  y: NA
  n: NA
  t: NA
  f: NA
---

This header passes validation at https://www.yamllint.com/, but when reading it with rmarkdown::yaml_front_matter() some parameter names are not handled correctly:

ymlthis::draw_yml_tree(
  rmarkdown::yaml_front_matter(
    textConnection("---\nparams:\n  x: NA\n  y: NA\n  n: NA\n  t: NA\n  f: NA\n---")
  )
)
└── params:
    ├── x: NA
    ├── 'TRUE': NA
    ├── 'FALSE': NA
    ├── t: NA
    └── f: NA

The problem occurs for other parameter names such as Yes and yes but, interestingly, not with T or t. The root cause lies in yaml::yaml.load because the underlying parser supports YAML 1.1 rather than YAML 1.2. The fix is to quote the problematic parameter names:

ymlthis::draw_yml_tree(
  rmarkdown::yaml_front_matter(
    textConnection("---\nparams:\n  x: NA\n  'y': NA\n  'n': NA\n  t: NA\n  f: NA\n---")
  )
)
└── params:
    ├── x: NA
    ├── 'y': NA
    ├── 'n': NA
    ├── t: NA
    └── f: NA

autoquarto attempts to handle the problem by converting any parameter names that appear as TRUE to y and any that appear as FALSE to n, but this obviously is not robust as more than one correct parameter name is mapped to each incorrect one.

Also relevant:

• https://stackoverflow.com/questions/75595253/rmarkdownyaml-front-matter-converts-some-parameter-names-to-true
• Key n is mapped to FALSE in simple example vubiostat/r-yaml#122