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Enum

Describes the possible expectations for enum values.

ExpectationNegatedSummary
IsEqualToIsNotEqualToequal to the expected value
IsOneOfIsNotOneOfequal to one of the expected values
HasValuenegated comparisonhas the expected underlying numeric value
IsDefinedIsNotDefineda named member of the enum
HasFlagDoesNotHaveFlaghas the expected flag set

The samples on this page use the following enum:

enum Genre { Rock = 1, Pop = 2, Jazz = 3, Blues = 4 }

Equality​

You can verify that the enum is equal to another one or not:

await Expect.That(Genre.Rock).IsEqualTo(Genre.Rock);
await Expect.That(Genre.Rock).IsNotEqualTo(Genre.Jazz);

One of​

You can verify that the enum is one of many alternatives:

await Expect.That(Genre.Rock).IsOneOf(Genre.Rock, Genre.Pop, Genre.Jazz);
await Expect.That(Genre.Blues).IsNotOneOf(Genre.Rock, Genre.Pop, Genre.Jazz);

Value​

You can verify that the enum has a given underlying numeric value or not:

await Expect.That(Genre.Rock).HasValue(1);
await Expect.That(Genre.Rock).HasValue().NotEqualTo(2);
await Expect.That(Genre.Jazz).HasValue().GreaterThan(2);

The Has… expectations for a number or a TimeSpan, e.g. HasLength(), HasCount(), HasYear() or HasMajor(), continue with one of the following comparisons, each with a negated counterpart:

ComparisonNegatedSucceeds when the value is
EqualTo(x)NotEqualTo(x)equal to x
GreaterThan(x)NotGreaterThan(x)greater than x
GreaterThanOrEqualTo(x)NotGreaterThanOrEqualTo(x)greater than or equal to x
LessThan(x)NotLessThan(x)less than x
LessThanOrEqualTo(x)NotLessThanOrEqualTo(x)less than or equal to x
Between(min).And(max)NotBetween(min).And(max)between min and max, both bounds included

Passing the value directly, e.g. HasLength(10), is a shorthand for EqualTo.

The expected value is nullable, e.g. to pass a value mapped from a property. As the actual value is never null, EqualTo(null) fails and NotEqualTo(null) succeeds, while a comparison of order against null, such as GreaterThan(null) or Between(null).And(3), fails even when negated.

Every backing type from sbyte to ulong is covered. Each comparison takes a long or a ulong, so a member of a ulong-backed enum above long.MaxValue can be named as well:

enum Big : ulong { Max = ulong.MaxValue }

await Expect.That(Big.Max).HasValue(ulong.MaxValue);
await Expect.That(Big.Max).HasValue().GreaterThan(0);

Defined​

You can verify that the enum has a defined value or not:

await Expect.That((Genre)3).IsDefined()
  .Because("3 corresponds to 'Jazz'");
await Expect.That((Genre)5).IsNotDefined()
  .Because("5 is no valid genre");

Flags​

You can verify that the enum has a specific flag or not:

using System.Text.RegularExpressions;

RegexOptions options = RegexOptions.Multiline | RegexOptions.IgnoreCase;

await Expect.That(options).HasFlag(RegexOptions.IgnoreCase);
await Expect.That(options).DoesNotHaveFlag(RegexOptions.ExplicitCapture);

Unlike the property-style Has… expectations such as HasValue, HasFlag has no continuation: it asks whether a bit is set, not how two ordered values compare, so GreaterThan, Between and the rest would have no meaning for it.