R: Expect that a condition holds.

expect_that {testthat}

R Documentation

Expect that a condition holds.

Description

An expectation checks whether a single condition holds true. testthat currently provides the following expectations. See their documentation for more details

Usage

  expect_that(object, condition, info = NULL, label = NULL)

Arguments

`object`	object to test
`condition,`	a function that returns whether or not the condition is met, and if not, an error message to display.
`label`	object label. When `NULL`, computed from deparsed object.
`info`	extra information to be included in the message (useful when writing tests in loops).

Details

is_true: truth
is_false: falsehood
is_a: inheritance
equals: equality with numerical tolerance
is_equivalent_to: equality ignoring attributes
is_identical_to: exact identity
matches: string matching
prints_text: output matching
throws_error: error matching
gives_warning: warning matching
shows_message: message matching
takes_less_than: performance

Expectations are arranged into tests with test_that and tests are arranged into contexts with context.

Examples

expect_that(5 * 2, equals(10))
expect_that(sqrt(2) ^ 2, equals(2))
## Not run: 
expect_that(sqrt(2) ^ 2, is_identical_to(2))

## End(Not run)

[Package testthat version 0.6 Index]