Simplify how I handle groups

[etiennebacher]

It is much easier to simply give a few attributes to the data when I run group_by(), then check these attributes in each function and use $groupby() + $agg() or $over() as I want. Then, just a custom print method to show groups and maintain_order argument.

TODO:

• check that everything is good with tidyverse namespaces
• check that all functions that can be applied per group work correctly (see commit 704f2bf)
• fix the lazy tests (see "exceptions" in tinytest/setup.R)

[etiennebacher]

Thanks for the investigation. I didn't understand whether you asked what the issue was here, but here's an example:

library(polars)

fake_group_by <- function(data, vars) {
  attr(data, "pl_grps") <- vars
  data
}

dat <- pl$DataFrame(iris)

# normal
attributes(fake_group_by(dat, "Species"))
#> $class
#> [1] "DataFrame"
#> 
#> $pl_grps
#> [1] "Species"

# there shouldn't be an attribute "pl_grps" here, hence the need to clone the
# data first
attributes(dat)
#> $class
#> [1] "DataFrame"
#> 
#> $pl_grps
#> [1] "Species"

Anyway, I'm just hiding the comments to save some space, thanks again ;)

[sorhawell]

but here's an example: ...

oh yes exactly 👍