public ResultOrErrorDetails <TDestination> Map <TDestination>(Func <T, TDestination> mapper)
{
if (mapper == null)
{
throw new ArgumentNullException(nameof(mapper));
}
if (!_result.IsDefined)
{
if (typeof(T) == typeof(TDestination))
{
//@ return this;
}
return(ResultOrErrorDetails <TDestination> .FromError(_error.Value));
}
var newResult = mapper(_result.Value);
if (newResult == null)
{
throw new ArgumentException($"The provided {nameof(mapper)} returned null, which is not valid");
}
if ((typeof(T) == typeof(TDestination)) && newResult.Equals(_result.Value))
{
//@ return this;
}
return(new ResultOrErrorDetails <TDestination>(newResult, _error));
}
private static void EqualsTests()
{
QUnit.Module("Equals(..)");
QUnit.Test("An instance of NonBlankTrimmedString is found to be equal to itself", assert =>
{
var x = new NonBlankTrimmedString("xyz");
AssertEqualsViaNonBlankTrimmedStringEqualsCall(assert, x, x, shouldBeEqual: true);
});
QUnit.Test("Two instances of NonBlankTrimmedString with the same value are found to be equal when compared as NonBlankTrimmedString", assert =>
{
var x = new NonBlankTrimmedString("xyz");
var y = new NonBlankTrimmedString("xyz");
AssertEqualsViaNonBlankTrimmedStringEqualsCall(assert, x, y, shouldBeEqual: true);
});
QUnit.Test("Two instances of NonBlankTrimmedString with the same value are found to be equal when compared as generic type param of NonBlankTrimmedString", assert =>
{
var x = new NonBlankTrimmedString("xyz");
var y = new NonBlankTrimmedString("xyz");
AssertEqualsViaSharedGenericTypeEqualsCall(assert, x, y, shouldBeEqual: true);
});
QUnit.Test("Two instances of NonBlankTrimmedString with the same value are found to be equal when compared as Object", assert =>
{
var x = new NonBlankTrimmedString("xyz");
var y = new NonBlankTrimmedString("xyz");
AssertEqualsViaObjectEqualsCall(assert, x, y, shouldBeEqual: true);
});
// There was a hack in ProductiveRage.Immutable to help Optional<T>'s Equals implementation work when T is an [ObjectLiteral] but that isn't required with the hacks in this library
// (so, once I'm happy with this all, I'll remove them from ProductiveRage.Immutable, so 3.2.0 will have the hacks removed that were introduced in 3.1.0 - for now, the tests here
// are referencing the 3.0.0 NuGet package, which doesn't have the hacks in it)
QUnit.Test("Two instances of Optional<NonBlankTrimmedString> with the same value are found to be equal when compared as NonBlankTrimmedString", assert =>
{
var x = Optional.For(new NonBlankTrimmedString("xyz"));
var y = Optional.For(new NonBlankTrimmedString("xyz"));
AssertEqualsViaOptionalNonBlankTrimmedStringEqualsCall(assert, x, y, shouldBeEqual: true);
});
QUnit.Test("Two instances of Optional<NonBlankTrimmedString> with the same value are found to be equal when compared as generic type param of NonBlankTrimmedString", assert =>
{
var x = Optional.For(new NonBlankTrimmedString("xyz"));
var y = Optional.For(new NonBlankTrimmedString("xyz"));
AssertEqualsViaSharedGenericTypeEqualsCall(assert, x, y, shouldBeEqual: true);
});
QUnit.Test("Two instances of Optional<NonBlankTrimmedString> with the same value are found to be equal when compared as Object", assert =>
{
var x = Optional.For(new NonBlankTrimmedString("xyz"));
var y = Optional.For(new NonBlankTrimmedString("xyz"));
AssertEqualsViaObjectEqualsCall(assert, x, y, shouldBeEqual: true);
});
QUnit.Test("Two instances of NonBlankTrimmedString with the same value are NOT equal if they are of different types when compared as NonBlankTrimmedString", assert =>
{
var x = new NonBlankTrimmedString("xyz");
var y = new ClassName("xyz");
AssertEqualsViaNonBlankTrimmedStringEqualsCall(assert, x, y, shouldBeEqual: false);
});
QUnit.Test("Two instances of NonBlankTrimmedString with the same value are NOT equal if they are of different types when compared as generic type param of NonBlankTrimmedString", assert =>
{
var x = new NonBlankTrimmedString("xyz");
var y = new ClassName("xyz");
AssertEqualsViaSharedGenericTypeEqualsCall(assert, x, y, shouldBeEqual: false);
});
QUnit.Test("Two instances of NonBlankTrimmedString with the same value are NOT equal if they are of different types when compared as Object", assert =>
{
var x = new NonBlankTrimmedString("xyz");
var y = new ClassName("xyz");
AssertEqualsViaObjectEqualsCall(assert, x, y, shouldBeEqual: false);
});
// This tests a few issues that have been encountered after using [ObjectLiteral] in more places - the FixObjectLiteralEqualsHack approach means that the implicit operator will
// not reliably be called when comparing an Optional<T> to T (the fix for that is in 4.1.0 of ProductiveRage.Immutable) and FixObjectLiteralEqualsHack now supports "falling
// through" equality checks if false is returned (so is comparing a NonBlankTrimmedString, which is an [ObjectLiteral], to an Optional<NonBlankTrimmedString> then the Equals
// check made against the NonBlankTrimmedString's Equals method will return false as it is unaware of Optional's implicit casting support and so other Equals methods need to
// be give opportunity to run) and it tests a bug with FixObjectLiteralEqualsHack relating to different generic types where the cached Equals lookup for an [ObjectLiteral]
// generic class would result in type checks against the generic type parameters being incorrect.
QUnit.Test("Integration tests around NonBlankTrimmedString / Optional / another [ObjectLiteral]", assert =>
{
var stringValue = new NonBlankTrimmedString("test");
var optionalOfString = Optional.For(stringValue);
var resultOrErrorOfString = ResultOrErrorDetails.FromResult(stringValue);
assert.NotOk(Equals(optionalOfString, resultOrErrorOfString));
assert.Ok(Equals(optionalOfString, stringValue));
assert.Ok(Equals(stringValue, optionalOfString));
assert.Ok(Equals(ResultOrErrorDetails.FromResult("abc"), ResultOrErrorDetails.FromResult("abc")));
assert.Ok(Equals(ResultOrErrorDetails.FromResult(new NonBlankTrimmedString("abc")), ResultOrErrorDetails.FromResult(new NonBlankTrimmedString("abc"))));
assert.NotOk(Equals(ResultOrErrorDetails.FromResult(new NonBlankTrimmedString("abc")), ResultOrErrorDetails.FromResult("abc")));
});
}