get_modelmatrix for nlme doesn't fully incorporate all info

[mattansb]

Related to easystats/parameters#706

library(nlme)
library(effectsize)

data("mtcars")
mtcars$cyl <- factor(mtcars$cyl)

fm1 <- lme(mpg ~ cyl, mtcars, random = ~ 1| gear, 
           contrasts = list("cyl" = contr.sum))
insight::get_modelmatrix(fm1)
#>                     (Intercept) cyl6 cyl8
#> Mazda RX4                     1    1    0
#> Mazda RX4 Wag                 1    1    0
#> Datsun 710                    1    0    0
#> Hornet 4 Drive                1    1    0
#> Hornet Sportabout             1    0    1
#> Valiant                       1    1    0
#> Duster 360                    1    0    1
#> Merc 240D                     1    0    0
#> Merc 230                      1    0    0
#> Merc 280                      1    1    0
#> Merc 280C                     1    1    0
#> Merc 450SE                    1    0    1
#> Merc 450SL                    1    0    1
#> Merc 450SLC                   1    0    1
#> Cadillac Fleetwood            1    0    1
#> Lincoln Continental           1    0    1
#> Chrysler Imperial             1    0    1
#> Fiat 128                      1    0    0
#> Honda Civic                   1    0    0
#> Toyota Corolla                1    0    0
#> Toyota Corona                 1    0    0
#> Dodge Challenger              1    0    1
#> AMC Javelin                   1    0    1
#> Camaro Z28                    1    0    1
#> Pontiac Firebird              1    0    1
#> Fiat X1-9                     1    0    0
#> Porsche 914-2                 1    0    0
#> Lotus Europa                  1    0    0
#> Ford Pantera L                1    0    1
#> Ferrari Dino                  1    1    0
#> Maserati Bora                 1    0    1
#> Volvo 142E                    1    0    0
#> attr(,"assign")
#> [1] 0 1 1
#> attr(,"contrasts")
#> attr(,"contrasts")$cyl
#> [1] "contr.treatment"

expected behavior:

fm2 <- lm(mpg ~ cyl, mtcars,
          contrasts = list("cyl" = contr.sum))
insight::get_modelmatrix(fm2)
#>                     (Intercept) cyl1 cyl2
#> Mazda RX4                     1    0    1
#> Mazda RX4 Wag                 1    0    1
#> Datsun 710                    1    1    0
#> Hornet 4 Drive                1    0    1
#> Hornet Sportabout             1   -1   -1
#> Valiant                       1    0    1
#> Duster 360                    1   -1   -1
#> Merc 240D                     1    1    0
#> Merc 230                      1    1    0
#> Merc 280                      1    0    1
#> Merc 280C                     1    0    1
#> Merc 450SE                    1   -1   -1
#> Merc 450SL                    1   -1   -1
#> Merc 450SLC                   1   -1   -1
#> Cadillac Fleetwood            1   -1   -1
#> Lincoln Continental           1   -1   -1
#> Chrysler Imperial             1   -1   -1
#> Fiat 128                      1    1    0
#> Honda Civic                   1    1    0
#> Toyota Corolla                1    1    0
#> Toyota Corona                 1    1    0
#> Dodge Challenger              1   -1   -1
#> AMC Javelin                   1   -1   -1
#> Camaro Z28                    1   -1   -1
#> Pontiac Firebird              1   -1   -1
#> Fiat X1-9                     1    1    0
#> Porsche 914-2                 1    1    0
#> Lotus Europa                  1    1    0
#> Ford Pantera L                1   -1   -1
#> Ferrari Dino                  1    0    1
#> Maserati Bora                 1   -1   -1
#> Volvo 142E                    1    1    0
#> attr(,"assign")
#> [1] 0 1 1
#> attr(,"contrasts")
#> attr(,"contrasts")$cyl
#>   [,1] [,2]
#> 4    1    0
#> 6    0    1
#> 8   -1   -1

^{Created on 2022-01-07 by the reprex package (v2.0.1)}