glue::single_quote does not handle NA

[colearendt]

glue::glue() has a .na parameter that allows you to control how NA is treated.

I would argue that glue::single_quote(NA) should be NA or should at least be controllable. Honestly, in the use cases I was trying (generating SQL), either single_quote(NA) = NA or single_quote(NA) = '' made the most sense to me. "NA" feels weird in that it is neither single quoted nor a value consistent with the nature of NA.

var <- NA
glue::single_quote(glue::glue("hello {NA}", .na = ""))
#> [1] "'hello '"
glue::single_quote(glue::glue("hello {var}", .na = ""))
#> [1] "'hello '"

# my confusion rests here
glue::single_quote(NA)
#> [1] "NA"

glue::single_quote(NULL)
#> character(0)

^{Created on 2019-04-24 by the reprex package (v0.2.1)}

[jimhester]

If you were generating SQL why were you not using glue_sql()?

But anyway I agree the behavior is not correct, will fix it so these all return a NA value.

[colearendt]

Awesome, thanks! I don't really remember, to be honest 😬 I think I had a FR for glue_sql, but this is all I recorded. Next time I work on this project, I will definitely let you know if there is something other than ignorance of functionality that kept me from using glue_sql 😄