void FromDelegate()
{
IComparer comp = null;
Test.If.Action.ThrowsException(() => comp = DynamicComparer.FromDelegate(null), out ArgumentNullException ex1);
Test.If.Value.IsEqual(ex1.ParamName, "compare");
Test.IfNot.Action.ThrowsException(() => comp = DynamicComparer.FromDelegate((x, y) => 21), out Exception ex2);
}
void ComparisonInvokes()
{
IComparer comp = null;
Int32 result = 0;
comp = DynamicComparer.FromDelegate((x, y) => throw new NotImplementedException());
Test.If.Action.ThrowsException(() => result = comp.Compare(0, 1), out NotImplementedException ex1);
comp = DynamicComparer.FromDelegate((x, y) => 42);
Test.IfNot.Action.ThrowsException(() => result = comp.Compare(0, 1), out Exception ex2);
Test.If.Value.IsEqual(result, 42);
}
void FromDelegateT()
{
IComparer <Dummy> comp = null;
Int32 result = 0;
Test.If.Action.ThrowsException(() => comp = DynamicComparer.FromDelegate <Dummy>(null), out ArgumentNullException ex1);
Test.If.Value.IsEqual(ex1.ParamName, "compare");
Test.IfNot.Action.ThrowsException(() => comp = DynamicComparer.FromDelegate <Dummy>((x, y) => 42), out Exception ex2);
result = comp.Compare(0, 1);
Test.If.Value.IsEqual(result, 42);
}
void MaxIComparerT_ThrowsException()
{
IEnumerable <Dummy> notEmpty = new Dummy[] { null, -1, -1, null, 0, 1, 1 };
IEnumerable <Dummy> empty = Enumerable.Empty <Dummy>();
IEnumerable <Dummy> nulls = new Dummy[] { null, null };
Test.If.Action.ThrowsException(() => IEnumerableTExtensions.Maximum(null, null as IComparer <Dummy>), out ArgumentNullException ex1);
Test.If.Value.IsEqual(ex1.ParamName, "_this");
Test.If.Action.ThrowsException(() => IEnumerableTExtensions.Maximum(null, DynamicComparer.FromDelegate <Dummy>((x, y) => 0)), out ex1);
Test.If.Value.IsEqual(ex1.ParamName, "_this");
Test.If.Action.ThrowsException(() => notEmpty.Maximum(null as IComparer <Dummy>), out ex1);
Test.If.Value.IsEqual(ex1.ParamName, "comparer");
Test.If.Action.ThrowsException(() => empty.Maximum(DynamicComparer.FromDelegate <Dummy>((x, y) => 0)), out ArgumentException ex2);
Test.If.Value.IsEqual(ex2.ParamName, "_this");
Test.If.String.StartsWith(ex2.Message, "The enumeration is empty.");
Test.If.Action.ThrowsException(() => nulls.Maximum(DynamicComparer.FromDelegate <Dummy>((x, y) => 0)), out ex2);
Test.If.Value.IsEqual(ex2.ParamName, "_this");
Test.If.String.StartsWith(ex2.Message, "The enumeration only contains null values.");
}