LanguageExt.UnitTesting 3.0.19

LanguageExt.UnitTesting

Extension methods to simplify writing unit tests for code written using LanguageExt library. These extension methods throw an exception if expectation fails.

Avalable as LanguageExt.UnitTesting nuget package.

Option

• ShouldBeSome<T>(Action<T> someValidation)
• ShouldBeNone<T>()

Option<int> subject = UnitUnderTest();

// the following line throws an exception if subject is Option<int>.None 
// or the integer value wrapped by Some does not equal 5
subject.ShouldBeSome(some => Assert.Equal(5, some));

// the following line throws an exception if subject is not Option<int>.None
subject.ShouldBeNone();

Validation

• ShouldBeSuccess<TFail, TSuccess>(Action<TSuccess> successValidation)
• ShouldBeFail<TFail, TSuccess>(Action<IEnumerable<TFail>> failValidation)

Validation<string, int> subject = UnitUnderTest();

// the following line throws an exception if subject represents failure
// or in case of successful validation the integer value does not equal 5
subject.ShouldBeSuccess(success => Assert.Equal(5, success));

// the following line throws an exception if subject does not represent failed validation
// or in case of failed validation the failure value does not meet expectation
subject.ShouldBeFail(errors => Assert("value is not valid", errors.First()));

Either

• ShouldBeRight<TLeft, TRight>(Action<TRight> rightValidation)
• ShouldBeLeft<TLeft, TRight>(Action<TLeft> leftValidation)

Either<string, int> subject = UnitUnderTest();

// the following line throws an exception if subject represents left side of Either
// or in case of right side of Either when the integer value does not equal 5
subject.ShouldBeRight(right => Assert.Equal(5, right));

// the following line throws an exception if subject represents right side of Either
// or in case of left side of Either when the string value does not equal "abcd"
subject.ShouldBeLeft(left => Assert.Equal("abcd", left));

EitherAsync

• ShouldBeRight<TLeft, TRight>(Action<TRight> rightValidation)
• ShouldBeLeft<TLeft, TRight>(Action<TLeft> leftValidation)

EitherAsync<string, int> subject = UnitUnderTest();

// the following line throws an exception if subject represents left side of Either
// or in case of right side of Either when the integer value does not equal 5
await subject.ShouldBeRight(right => Assert.Equal(5, right));

// the following line throws an exception if subject represents right side of Either
// or in case of left side of Either when the string value does not equal "abcd"
await subject.ShouldBeLeft(left => Assert.Equal("abcd", left));

Try

• ShouldBeSuccess<T>(Action<T> successValidation)
• ShouldBeFail<T>(Action<Exception> failValidation)

Try<int> subject = UnitUnderTest();

// the following line throws an exception if subject represents failure
// or in case of successful try the integer value does not equal 5
subject.ShouldBeSuccess(success => Assert.Equal(5, success));

// the following line throws an exception if subject does not represent failure
// or in case of failure the exception has wrong message
subject.ShouldBeFail(ex => Assert.Equal("something went wrong", ex.Message));

TryAsync

• ShouldBeSuccess<T>(Action<T> successValidation)
• ShouldBeFail<T>(Action<Exception> failValidation)

TryAsync<int> subject = UnitUnderTest();

// the following line throws an exception if subject represents failure
// or in case of successful try the integer value does not equal 5
await subject.ShouldBeSuccess(success => Assert.Equal(5, success));

// the following line throws an exception if subject does not represent failure
// or in case of failure the  exception has wrong message
await subject.ShouldBeFail(ex => Assert.Equal("something went wrong", ex.Message));

TryOptionAsync

• ShouldBeSome<T>(Action<T> someValidation)
• ShouldBeNone<T>()
• ShouldBeFail<T>(Action<Exception> failValidation)

TryOptionAsync<int> subject = UnitUnderTest();

// the following line throws an exception if subject represents failure or Option<T>.None
// or the integer value wrapped by Some does not equal 5
await subject.ShouldBeSome(some => Assert.Equal(5, some));

// the following line throws an exception if subject is not Option<int>.None
await subject.ShouldBeNone();

// the following line throws an exception if subject does not represent failure
// or in case of failure the exception has wrong message
await subject.ShouldBeFail(ex => Assert.Equal("something went wrong", ex.Message));