compose_trans does not work where "reverse" is last

[davidhodge931]

library(scales)
#> Warning: package 'scales' was built under R version 4.3.1
demo_continuous(10^c(-2:4), trans = c("reverse", "log10"))
#> scale_x_continuous(trans = c("reverse", "log10"))
#> Error in `compose_trans()`:
#> ! Sequence of transformations yields invalid domain
#> Backtrace:
#>     ▆
#>  1. └─scales::demo_continuous(10^c(-2:4), trans = c("reverse", "log10"))
#>  2.   └─scales:::demo_ggplot(x, "scale_x_continuous", ...)
#>  3.     └─ggplot2 (local) scale(NULL, ...)
#>  4.       └─ggplot2::continuous_scale(...)
#>  5.         └─scales::as.trans(trans)
#>  6.           └─scales::compose_trans(!!!x)
#>  7.             └─rlang::abort("Sequence of transformations yields invalid domain")

^{Created on 2023-07-22 with reprex v2.0.2}

[teunbrand]

This behaviour makes sense because the reverse operation transforms the data by multiplying by -1 and you cannot take the log of negative numbers. The error that the domain has become invalid is appropriate I think.

[davidhodge931]

Maybe a sentence in help to tell people?

I'd guess most people would have no idea that the data is transformed by -1 when the scale is reversed