ShouldlyAsserting, the way it should be

Uri Goldstein (github/twitter: @urig)

Unit Tests

1. Arrange

2. Act

3. Assert

Starting Point

//Arrangevar target = new Calculator();

//Actvar actual = target.Sqrt(9.0);

//AssertAssert.AreEqual(actual, 3.0);

Shouldly

//Arrangevar target = new Calculator();

//Actvar actual= target.Sqrt(9.0);

//Assertactual.ShouldBe(3.0);

Shouldly + Readability

//Arrangevar calculator = new Calculator();

//Actvar sqrt_of_nine = calculator.Sqrt(9.0);

//Assertsqrt_of_nine.ShouldBe(3.0);

Shouldly + Readability = Win!

Assert.AreEqual(actual, 3.0);

sqrt_of_nine.ShouldBe(3.0);

Assert.AreEqual failed. Expected:<3>. Actual:<4>.

sqrt_of_nine should be 3 but was 4

ReallyAssert.That(names.IndexOfValue("Uri"), Is.EqualTo(2));

names.IndexOfValue("Uri").ShouldBe(2);

Expected 2 but was 1

names.IndexOfValue("Uri")should be 2

but was 1

Really ReallyAssert.AreEqual(new[] { 1, 2, 3 }, new[] { 1, 2, 4 });

(new[] { 1, 2, 3 }).ShouldBe(new[] { 1, 2, 4 });

Expected:<System.Int32[]>. Actual:<System.Int32[]>.

new[] { 1, 2, 3 }) should be [1, 2, 4] but was [1, 2, 3] difference [1, 2, *3*]

Syntactic SugarShouldBeShouldNotBeShouldBeOneOfShouldNotBeOneOfShouldBeGreaterThanShouldBeLessThanShouldBeOfTypeShouldBeAssignableToShouldBeInRangeShouldNotBeInRangeShouldAllBeShouldContainShouldNotContainShouldBeEmptyShouldNotBeEmpty

ShouldBeOneOfShouldBeSubsetOfShouldContainKeyShouldNotStartWithShouldEndWithShouldNotEndWithShouldMatchShouldBeNullOrEmptyShouldNotBeNullOrEmptyShouldContainShouldNotContainShouldContainWithoutWhitespaceShouldThrowShouldHavePropertyCompleteIn…

Example 1/3 - ShouldBeOneOfvar apu = new Person() { Name = "Apu" };var homer = new Person() { Name = "Homer" };var skinner = new Person() { Name = "Skinner" };var barney = new Person() { Name = "Barney" };var theBeSharps = new List<Person>() { homer, skinner, barney };

apu.ShouldBeOneOf(theBeSharps.ToArray());

Apu should be one of [Homer, Skinner, Barney] but was Apu

Source: http://docs.shouldly-lib.net/v2.4.0/docs/shouldbeoneof

Example 2/3 - ShouldSatisfyAllConditionsvar millionaire = new Person() { Name = "Homer", Salary = 30000 };

millionaire.ShouldSatisfyAllConditions(

() => millionaire.Name.ShouldBe("Mr.Burns"),() => millionaire.Salary.ShouldBeGreaterThan(1000000)

);millionaire should satisfy all the conditions specified, but does not. The following errors were found ...--------------- Error 1 ---------------

millionaire.Name should be "Mr.Burns" but was "Homer"--------------- Error 2 ---------------

millionaire.Salary should be greater than 1000000 but was 30000-----------------------------------------

Source: http://docs.shouldly-lib.net/v2.4.0/docs/shouldsatisfyallconditions

Example 3/3 - ShouldThrow (Async)Should.Throw<DivideByZeroException>(() => { return Task.Factory.StartNew(() => { var y = homer.Salary/denominator; }); return task; });

Should throw System.DivideByZeroException but does not

http://docs.shouldly-lib.net/v2.4.0/docs/shouldthrow-2

Shouldly

• Make your tests more readable.• Fail faster with excellent error messages.• Bonus: Async, Multi-conditions.

• Free Open Source Software.

http://up-for-grabs.net/

Just Jump In

Thank you!

Shouldly:

github.com/shouldly/shouldlynuget:

Let’s keep in touch:

twitter.com/urig