AutomatedTests

function TestAssertException (message) {
    this.name = "TestAssertException";
    this.message = message;
    this.stack = (new Error()).stack;
}

TestAssertException.prototype = new Error; // should be instanceof Error now

function TestLog(message, style) {
    if (!style) {
        style = "background: black; color: white; padding: 10px;";
    }

    const resetStyle = "background: transparent; color: black;";
    console.log(`%c${message}%c`, style, resetStyle);
}

class Test {
    describe(description, foo) {
        self = this;
        console.log(description.charAt(0).toUpperCase() + description.slice(1));
        foo(self);
    }

    it(description, foo) {
        this.describe(description, foo);
    }

    expect (expected) {
        return {
            toBe: function (assertion) {
                if (expected === assertion) {
                    TestLog("Teste [OK]", "background: palegreen; color: black; padding: 5px;");
                } else {
                    TestLog("Teste [NOK]", "background: lightcoral; color: white; padding: 5px;");
                    throw new TestAssertException();
                }
            }
        }
    }
}

class UnitTests extends Test {
    retornar2 () {
        this.it("deveria retornar 2", function (test) {
            test.expect(2).toBe(2);
        })
    }
}

class TestRunner {
    iniRun = 0;
    endRun = 0;
    excCount = 0;

    runAll () {
        var unitTests = new UnitTests();
        var methods = Reflect.ownKeys(Reflect.getPrototypeOf(unitTests)).filter(methodName => methodName != "constructor");
        for (var k in methods) {
            try {
                var method = methods[k];
                TestLog("Rodando teste [" + method + "]");
                this.iniRun++;
                unitTests[method]();
                this.endRun++;
            } catch (e) {
                this.excCount++;
            }
        }

        TestLog(`${this.endRun} testes passaram`, "background: seagreen; color: white; padding: 5px;");
        TestLog(`${this.excCount} testes falharam`, "background: red; color: white; padding: 5px;");
    }
}

var testRunner = new TestRunner();
testRunner.runAll();