library(testit)

rm(list = ls())
z = 5
assert('a list can be used as the parent frame for knit()', {
  # evaluate in a new environment; should create an object in current envir
  (!has_error(with(list(y = 4:8), knit('knit-envir.Rmd', quiet = TRUE))))
})

env = new.env()
env$y = 1:3
knit('knit-envir.Rmd', envir = env, quiet = TRUE)
assert('knit() creates objects in its envir argument', {
  (!exists('asdfqwerzxcv'))
  (exists('asdfqwerzxcv', envir = env))
})

assert('undefined external objects should cause errors', {
  (suppressMessages(has_error(knit('knit-envir.Rmd', quiet = TRUE))))  # y is not found
  (!has_error(with(list(y = letters), knit('knit-envir.Rmd', quiet = TRUE))))
})

file.remove('knit-envir.md')