Absolute Unit Test

A minimal unit testing library

Example

import { runTests, assert, assertEq, assertNeq, assertDeepEq, assertDeepNeq } from "absolute_unit_test";

class AbsoluteUnitTests {
    "assert should assert correctly"() {
        const isTrue = true;
        assert(isTrue, "isTrue should be true");
    }

    "assertEq should assert correctly"() {
        assertEq(10, 10);
        assertEq("10", "10");
        assertEq(true, true);
        assertEq(NaN, NaN);
        assertEq(0, 0);
        const sameSymbol = Symbol();
        assertEq(sameSymbol, sameSymbol);
    }

    "assertNeq should assert correctly"() {
        assertNeq(10, 12);
        assertNeq(10, "10");
        assertNeq(true, false);
        assertNeq(NaN, 1);
        assertNeq(+0, -0);
        assertNeq(Symbol(), Symbol());
    }

    "assertDeepEq should assert correctly"() {
        const shared = { something: 10 };
        const first = { inner: { shared } };
        const second = { inner: { shared } };
        assertDeepEq(first, second);

        first.inner.cycle = first;
        second.inner.cycle = second;
        assertDeepEq(first, second);
    }

    "assertDeepNeq should assert correctly"() {
        const shared = { something: 10 };
        const first = { inner: { shared, difference: 20 } };
        const second = { inner: { shared } };
        assertDeepNeq(first, second);

        shared.cycle = shared;
        assertDeepNeq(first, second);
    }
}

runTests(AbsoluteUnitTests);

Motivation

I was sick of huge bloated libraries for unit testing. Why do I need 3 or 4 different libraries just to test some code. To get started with almost all other unit testing frameworks you have to install the framework, a runner, an assertion library and probably some helpers/plugin libraries. I wanted something minimal and unassuming.

You will lose a bit of portability, I have only written this library to work in modern node and browser environments. It makes uses of Object.is, Promise, WeakSet, for .. of and Reflect.

Tests

1. Define a class
2. Add some methods
3. runTests(TestClass1, TestClass2, ...)
4. Profit

How to organise multiple test classes is left as an exercise for the reader.

Assertions

Anything that throws an exception can be used as an assert.

Before/After

Nothing built-in, if you want to run some code before a test, just call a function.

Equality

The default assertions use Object.is for equality testing, this is exactly the same as using === except that Object.is(NaN, NaN) is true and Object.is(+0, -0) is false.

The deep equality assertions do not use a recursive algorithm. They maintain an internal stack, they only process cycles once and they they skip shared references since they are always the same.