Formula expansion using interaction terms fails to include both raw interaction term and it crossed against exposure

[shah-in-boots]

As we can see below, there should be an formula level that looks like... hp ~ wt + am + wt:am instead, however, it splits the interaction terms.

library(vlndr)
#> Loading required package: vctrs
#> Loading required package: tibble
#> 
#> Attaching package: 'tibble'
#> The following object is masked from 'package:vctrs':
#> 
#>     data_frame
fmls(hp ~ .x(wt) + .i(am), pattern = "parallel")
#> Interaction term `am` was applied to exposure term `wt`
#> hp ~ wt + am
#> hp ~ wt + wt:am

^{Created on 2024-01-25 with reprex v2.1.0}

As exploring this issue, here are trouble spots that have been found:

• [ ] When explicitly giving an interaction term, y ~ x + i + x:i, grouping does not occur at the tm() level
• [ ] Parallel term/formula expansion pattern fails to account for multiple variables (e.g. grouped variables)

[shah-in-boots]

Fixed in most recent commit