public void Usage_With_Unified_On()
{
var dispatcher = new DoubleDispatcher <object>();
dispatcher.On <Constant, Variable>((c, v) => { Assert.Fail(); });
var wasRightComboPicked = false;
dispatcher.On <Addition, Constant>((a, m) => { wasRightComboPicked = true; });
dispatcher.Dispatch(new Addition(), new Constant());
wasRightComboPicked.Should().BeTrue();
}
public void If_No_Fitting_Handler_Defined_Calls_FallbackHandler()
{
var wasFallbackCalled = false;
var dispatcher = new DoubleDispatcher <object> {
FallbackHandler = (l, r) => wasFallbackCalled = true
};
dispatcher.OnLeft <Constant>().OnRight <Variable>().Do((c, v) => { Assert.Fail(); });
dispatcher.OnLeft <Addition>().OnRight <Constant>().Do((a, m) => { Assert.Fail(); });
dispatcher.Dispatch(new Constant(), new Constant());
wasFallbackCalled.Should().BeTrue();
}
public void Picks_Right_Handler_If_Defined()
{
var dispatcher = new DoubleDispatcher <object> {
FallbackHandler = (l, r) => Assert.Fail()
};
dispatcher.OnLeft <Constant>().OnRight <Variable>().Do((c, v) => { Assert.Fail(); });
var wasRightComboPicked = false;
dispatcher.OnLeft <Addition>().OnRight <Constant>().Do((a, m) => { wasRightComboPicked = true; });
dispatcher.Dispatch(new Addition(), new Constant());
wasRightComboPicked.Should().BeTrue();
}
public void Usage_With_Predicates()
{
var dispatcher = new DoubleDispatcher <object>();
var wasHandlerCalled = false;
dispatcher.OnLeft <Addition>().OnRight <Constant>(c => c.Value > 0).Do((a, c) => wasHandlerCalled = true);
dispatcher.Dispatch(new Addition(), new Constant {
Value = -1
});
wasHandlerCalled.Should().BeFalse();
dispatcher.Dispatch(new Addition(), new Constant {
Value = 13
});
wasHandlerCalled.Should().BeTrue();
}