test_file helper #1755
Description
It would be very useful to have a function that helps you test a single file, allowing you to iterate more rapidly when working on a single a file. The function should take a file path as an argument - it should be a path to a file in R/ or tests/testthat. If omitted, it should default to using the RStudio active file.
It will need to:
- Save all open files
- Re-load the code
- Execute the single test file
Ideally it would be paired with a test_coverage() helper.