r-package-development

# R package development ## Key commands ``` # Run code in the package Rscript -e "devtools::load_all(); code" # Run all tests Rscript -e "devtools::test()" # Run all tests for files starting with {name} Rscript -e "devtools::test(filter = '^{name}')" # Run all tests for R/{name}.R Rscript -e "devtools::test_active_file('R/{name}.R')" # Run a single test "blah" for R/{name}.R Rscript -e "devtools::test_active_file('R/{name}.R', desc = 'blah')" # Redocument the package Rscript -e "devtools::document()" # Check pkgdown documentation Rscript -e "pkgdown::check_pkgdown()" # Check the package with R CMD check Rscript -e "devtools::check()" # Format code air format . ``` ## Coding * Always run `air format .` after generating code. * Use the base pipe operator (`|>`) not the magrittr pipe (`%>%`). * Use `\() ...` for single-line anonymous functions. For all other cases, use `function() {...}`. ## Testing - Tests for `R/{name}.R` go in `tests/testthat/test-{name}.R`. - All new code should have an accompanying test. - If there are existing tests, place new tests next to similar existing tests. - Strive to keep tests minimal with few comments. - Avoid `expect_true()` and `expect_false()` in favour of a specific expectation which will give a better failure message. - When testing errors and warnings, don't use `expect_error()` or `expect_warning()`. Instead, use `expect_snapshot(error = TRUE)` for errors and `expect_snapshot()` for warnings because these allow the user to r...