testthat (version 0.2)

expect_that: Expect that a condition holds.

Description

Expect that a condition holds.

Usage

expect_that(object, condition, info)

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)

Details

An expectation checks whether a single condition holds true. testthat currently provides the following expectations. See their documentation for more 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
• 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))
expect_that(sqrt(2) ^ 2, is_identical_to(2))