Name: ChainingAssertion.Bin
Author: neuecc, J.Sakamoto

ChainingAssertion.Bin — nugetz

// "Is" extend on all object and has three overloads.

// This same as Assert.AreEqual(25, Math.Pow(5, 2))
Math.Pow(5, 2).Is(25);

// lambda predicate assertion.
// This same as Assert.IsTrue("foobar".StartsWith("foo") && "foobar".EndWith("bar"))
"foobar".Is(s => s.StartsWith("foo") && s.EndsWith("bar"));

// collection assert takes variable arguments
// This same as CollectionAssert.AreEqual(Enumerable.Range(1,5), new[]{1, 2, 3, 4, 5})
Enumerable.Range(1, 5).Is(1, 2, 3, 4, 5);

var array = new[] { 1, 3, 7, 8 };

array.Count().Is(4);
array.Contains(8).IsTrue(); // IsTrue() == Is(true)
array.All(i => i < 5).IsFalse(); // IsFalse() == Is(false)
array.Any().Is(true);
new int[] { }.Any().Is(false);   // IsEmpty
array.OrderBy(x => x).Is(array); // IsOrdered

// Null Assertions
Object obj = null;
obj.IsNull();             // Assert.IsNull(obj)
new Object().IsNotNull(); // Assert.IsNotNull(obj)

// Not Assertion
"foobar".IsNot("fooooooo"); // Assert.AreNotEqual
new[] { "a", "z", "x" }.IsNot("a", "x", "z"); /// CollectionAssert.AreNotEqual

// ReferenceEqual Assertion
var tuple = Tuple.Create("foo");
tuple.IsSameReferenceAs(tuple); // Assert.AreSame
tuple.IsNotSameReferenceAs(Tuple.Create("foo")); // Assert.AreNotSame

// Type Assertion
"foobar".IsInstanceOf<string>(); // Assert.IsInstanceOfType
(999).IsNotInstanceOf<double>(); // Assert.IsNotInstanceOfType

var lower = new[] { "a", "b", "c" };
var upper = new[] { "A", "B", "C" };

// Comparer CollectionAssert, use IEqualityComparer<T> or Func<T,T,bool> delegate
lower.Is(upper, StringComparer.InvariantCultureIgnoreCase);
lower.Is(upper, (x, y) => x.ToUpper() == y.ToUpper());

// or you can use Linq to Objects - SequenceEqual
lower.SequenceEqual(upper, StringComparer.InvariantCultureIgnoreCase).Is(true);

class MyClass
{
    public int IntProp { get; set; }
    public string StrField;
}

var mc1 = new MyClass() { IntProp = 10, StrField = "foo" };
var mc2 = new MyClass() { IntProp = 10, StrField = "foo" };

mc1.IsStructuralEqual(mc2); // deep recursive value equality compare

mc1.IntProp = 20;
mc1.IsNotStructuralEqual(mc2);

// a class and private field/property/method.
public class PrivateMock
{
    private string privateField = "homu";

    private string PrivateProperty
    {
        get { return privateField + privateField; }
        set { privateField = value; }
    }

    private string PrivateMethod(int count)
    {
        return string.Join("", Enumerable.Repeat(privateField, count));
    }
}

// call private property.
var actual = new PrivateMock().AsDynamic().PrivateProperty;
Assert.AreEqual("homuhomu", actual);

// dynamic can't invoke extension methods.
// if you want to invoke "Is" then cast type.
(new PrivateMock().AsDynamic().PrivateMethod(3) as string).Is("homuhomuhomu");

// set value
var mock = new PrivateMock().AsDynamic();
mock.PrivateProperty = "mogumogu";
(mock.privateField as string).Is("mogumogu");

// a model
public class Person
{
    public int Age { get; set; }
    public string FamilyName { get; set; }
    public string GivenName { get; set; }
}

[TestMethod]
public void TestMethod()
{
    // this assertion is fail
    var person = new Person { Age = 50, FamilyName = "Yamamoto", GivenName = "Tasuke" };
    person.Is(p => p.Age <= 10 && p.FamilyName == "Yamada" && p.GivenName == "Tarou");
}

// Exception Test(alternative of ExpectedExceptionAttribute)
// AssertEx.Throws does not allow derived type
// AssertEx.Catch allows derived type
// AssertEx.ThrowsContractException catch only Code Contract's ContractException
AssertEx.Throws<ArgumentNullException>(() => "foo".StartsWith(null));
AssertEx.Catch<Exception>(() => "foo".StartsWith(null));
AssertEx.ThrowsContractException(() => /* contract method */);

// return value is occured exception
var ex = AssertEx.Throws<InvalidOperationException>(() =>
{
    throw new InvalidOperationException("foobar operation");
});
ex.Message.Is(s => s.Contains("foobar")); // additional exception assertion

// must not throw any exceptions
AssertEx.DoesNotThrow(() =>
{
    // code
});

[TestClass]
public class UnitTest
{
    public TestContext TestContext { get; set; }

    [TestMethod]
    [TestCase(1, 2, 3)]
    [TestCase(10, 20, 30)]
    [TestCase(100, 200, 300)]
    public void TestMethod2()
    {
        TestContext.Run((int x, int y, int z) =>
        {
            (x + y).Is(z);
            (x + y + z).Is(i => i < 1000);
        });
    }
}

[TestMethod]
[TestCaseSource("toaruSource")]
public void TestTestCaseSource()
{
    TestContext.Run((int x, int y, string z) =>
    {
        string.Concat(x, y).Is(z);
    });
}

public static object[] toaruSource = new[]
{
    new object[] {1, 1, "11"},
    new object[] {5, 3, "53"},
    new object[] {9, 4, "94"}
};

[TestClass]
public class UnitTest
{
    public TestContext TestContext { get; set; }

    [TestMethod]
    [TestCase(1, 2, 3)]
    [TestCase(10, 20, 30)]
    [TestCase(100, 200, 300)]
    public async Task TestTestCaseAsync()
    {
        await TestContext.RunAsync((int x, int y, int z) =>
        {
            var actual = await SumAsync(x, y);
            actual.Is(z);
        });
    }
}

jsakamoto/ChainingAssertion.Binv2.1.0

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Readme

Chaining Assertion

Binary only edition packages

Is

CollectionAssert

Other Assertions

Advanced Collection Assertion

StructuralEqual

DynamicAccessor

Is(lambda)'s error message

Exception Test (for MSTest)

Parameterized Test (for MSTest)

TestCaseSource (for MSTest)

Parameterized Test - Async version (for MSTest)