Indexing error with unnamed two-sided formula

[statisfactions]

specify() with a single formula provides a huge variety of mysterious output:

suppressPackageStartupMessages(library(simpr))
specify(y ~ 1 + 2)
#> Formula specification for 'x' detected. Assuming 'x' is the first formula.
#> 
#> To hide this message, or to avoid moving this formula first, use a different variable name.
#> Error in `purrr::pmap()`:
#> ℹ In index: 1.
#> ℹ With name: x.
#> Caused by error in `x[[2]][-1]`:
#> ! object of type 'symbol' is not subsettable
#> Backtrace:
#>      ▆
#>   1. ├─generics::specify(y ~ 1 + 2)
#>   2. ├─simpr:::specify.formula(y ~ 1 + 2)
#>   3. │ └─simpr:::add_specification(...)
#>   4. │   └─purrr::pmap(...)
#>   5. │     └─purrr:::pmap_("list", .l, .f, ..., .progress = .progress)
#>   6. │       ├─purrr:::with_indexed_errors(...)
#>   7. │       │ └─base::withCallingHandlers(...)
#>   8. │       ├─purrr:::call_with_cleanup(...)
#>   9. │       └─simpr (local) .f(.l[[1L]][[i]], .l[[2L]][[i]], .l[[3L]][[i]], ...)
#>  10. │         └─x[[2]][-1] %>% as.list() %>% purrr::map_chr(deparse)
#>  11. ├─purrr::map_chr(., deparse)
#>  12. │ └─purrr:::map_("character", .x, .f, ..., .progress = .progress)
#>  13. │   └─purrr:::vctrs_vec_compat(.x, .purrr_user_env)
#>  14. ├─base::as.list(.)
#>  15. └─purrr (local) `<fn>`(`<ntSbsttE>`)
#>  16.   └─cli::cli_abort(...)
#>  17.     └─rlang::abort(...)

^{Created on 2024-07-14 with reprex v2.0.2}

There's both the confusion about the default option of specify() as well as the baffling indexing error which looks to be based on some internals that need some refactoring.

[statisfactions]

Leaving open but will not fix for 0.2.0