expect

Small assertion module.

|Function|Description| |:---|:---| |expect(a).toBe(b)|Asserts that a and b are the same (===).| |expect(a).toBeInstanceOf(b)|Asserts that a is an instance of b| |expect(a).toEqual(b)|If b is a primitive then:a === bIf b is not a primitive:• Asserts same prototype• Asserts same properties• Asserts property value recursively with toEqual| |expect(a).toHaveProperty(b)|Asserts that object a has an enumerable/non-enumerable property called b.| |expect(a).toHaveSubString(b)|Asserts that string a contains the sub-string b.| |expect(fn).toThrowError()|Asserts that fn throws an error.| |expect(fn).toThrowError(message)|Asserts that fn throws an error with a message containing message.|

All assertions (except toThrowError) can be negated with .not:

expect(1).not.toBe(2)

Example usage:

const {createExpectationsContext} = require("expect")
const {expect, end} = createExpectationsContext()

expect(1).toBe(1)
end()