things to refactor

[erblast]

• [ ] leaner functions with reduced but preciseroxygen documentation
• [ ] use rlang::.data fo non standard eval https://resources.rstudio.com/rstudio-developed/tidyeval-2
• [ ] use stopifnot() to check var types of all functions
• [ ] use @inheritParam roxygen tag
• [ ] in a test file make smaller test_that() functions and execute code used by many tests outside of the test_that() functions