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## ----include = FALSE----------------------------------------------------------
knitr::opts_chunk$set(
collapse = TRUE,
comment = "#>"
)
## -----------------------------------------------------------------------------
library(testthat)
## ----include = FALSE----------------------------------------------------------
op <- options()
## -----------------------------------------------------------------------------
sloppy <- function(x, sig_digits) {
options(digits = sig_digits)
print(x)
}
pi
sloppy(pi, 2)
pi
## ----include = FALSE----------------------------------------------------------
options(op)
## -----------------------------------------------------------------------------
neat <- function(x, sig_digits) {
op <- options(digits = sig_digits)
on.exit(options(op), add = TRUE, after = FALSE)
print(x)
}
pi
neat(pi, 2)
pi
## -----------------------------------------------------------------------------
test_that("can print one digit of pi", {
op <- options(digits = 1)
on.exit(options(op), add = TRUE, after = FALSE)
expect_output(print(pi), "3")
})
pi
## ----eval = FALSE-------------------------------------------------------------
# op <- options(digits = 1)
# on.exit(options(op), add = TRUE, after = FALSE)
## -----------------------------------------------------------------------------
neat <- function(x, sig_digits) {
op <- options(digits = sig_digits)
withr::defer(options(op))
print(x)
}
## ----eval = FALSE-------------------------------------------------------------
# withr::defer(print("hi"))
# #> Setting deferred event(s) on global environment.
# #> * Execute (and clear) with `deferred_run()`.
# #> * Clear (without executing) with `deferred_clear()`.
#
# withr::deferred_run()
# #> [1] "hi"
## -----------------------------------------------------------------------------
local_digits <- function(sig_digits) {
op <- options(digits = sig_digits)
on.exit(options(op), add = TRUE, after = FALSE)
}
neater <- function(x, sig_digits) {
local_digits(1)
print(x)
}
neater(pi)
## -----------------------------------------------------------------------------
local_digits <- function(sig_digits, env = parent.frame()) {
op <- options(digits = sig_digits)
withr::defer(options(op), env)
}
neater(pi)
## -----------------------------------------------------------------------------
test_that("withr lets us write custom helpers for local state manipulation", {
local_digits(1)
expect_output(print(exp(1)), "3")
local_digits(3)
expect_output(print(exp(1)), "2.72")
})
print(exp(1))
## -----------------------------------------------------------------------------
neatest <- function(x, sig_digits) {
withr::local_options(list(digits = sig_digits))
print(x)
}
neatest(pi, 3)
## -----------------------------------------------------------------------------
message2 <- function(...) {
if (!isTRUE(getOption("verbose"))) {
return()
}
message(...)
}
## -----------------------------------------------------------------------------
message3 <- function(..., verbose = getOption("verbose")) {
if (!isTRUE(verbose)) {
return()
}
message(...)
}
## -----------------------------------------------------------------------------
test_that("message2() output depends on verbose option", {
withr::local_options(verbose = TRUE)
expect_message(message2("Hi!"))
withr::local_options(verbose = FALSE)
expect_message(message2("Hi!"), NA)
})
## ----eval = FALSE-------------------------------------------------------------
# local_create_package <- function(dir = file_temp(), env = parent.frame()) {
# old_project <- proj_get_()
#
# # create new folder and package
# create_package(dir, open = FALSE) # A
# withr::defer(fs::dir_delete(dir), envir = env) # -A
#
# # change working directory
# setwd(dir) # B
# withr::defer(setwd(old_project), envir = env) # -B
#
# # switch to new usethis project
# proj_set(dir) # C
# withr::defer(proj_set(old_project, force = TRUE), envir = env) # -C
#
# dir
# }
## ----eval = FALSE-------------------------------------------------------------
# test_that("use_roxygen_md() adds DESCRIPTION fields", {
# pkg <- local_create_package()
# use_roxygen_md()
#
# expect_true(uses_roxygen_md())
# expect_equal(desc::desc_get("Roxygen", pkg)[[1]], "list(markdown = TRUE)"))
# expect_true(desc::desc_has_fields("RoxygenNote", pkg))
# })
## ----eval = FALSE-------------------------------------------------------------
# # Run before any test
# write.csv("mtcars.csv", mtcars)
#
# # Run after all tests
# withr::defer(unlink("mtcars.csv"), teardown_env())
|
