testthat (version 0.9.1)

expect_that: 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.

info

extra information to be included in the message (useful when writing tests in loops).

label

object label. When NULL, computed from deparsed object.

Value

• the (internal) expectation result as an invisible list

Details

• is_true: truth
• is_false: falsehood
• is_a: inheritance
• equals: equality with numerical tolerance
• equals_reference: equality relative to a reference
• 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.

See Also

fail for an expectation that always fails.

Examples

expect_that(5 * 2, equals(10))
expect_that(sqrt(2) ^ 2, equals(2))
expect_that(sqrt(2) ^ 2, is_identical_to(2))