public void TryDropPossibility_WhenRejectedByParent_LeavesUnchanged()
{
var fakePossibilities = new FakePossibility[] {
new FakePossibility(),
new FakePossibility(),
};
var childOptional = OptionalObjective.CreateWithPossibilities(
Possibilities.CreatePossibilities(new(), 2), 1);
var possibilities = fakePossibilities.Cast <IPossibility>().Append(childOptional).ToArray();
var optional = OptionalObjective.CreateWithPossibilities(possibilities, 3);
var parent = new FakeObjective(isRequired: true);
parent.CanDropPossibilities = false;
IPossibility possibility = optional;
IObjective objective = optional;
Link.CreateConnectedLink(possibility, parent);
var childToDrop = fakePossibilities[0];
Assert.False(objective.TryDropPossibility(childToDrop.AttachedObjectives.First()));
Assert.Equal(NodeState.UNKNOWN, optional.State);
Assert.Empty(parent.DroppedPossibilities);
Assert.Empty(fakePossibilities[0].DroppedFromObjectives);
Assert.Empty(fakePossibilities[1].DroppedFromObjectives);
Assert.Equal(NodeState.UNKNOWN, childOptional.State);
}
public void TryDropAndReturnPossibility_WhenOkWithParent_Succeeds()
{
var fakePossibilities = new FakePossibility[] {
new FakePossibility(),
new FakePossibility(),
};
var optional = OptionalObjective.CreateWithPossibilities(fakePossibilities, 1);
var parent = new FakeObjective(isRequired: true);
IPossibility possibility = optional;
IObjective objective = optional;
var linkToParent = Link.CreateConnectedLink(possibility, parent);
var childToDrop = fakePossibilities[0];
Assert.True(objective.TryDropPossibility(childToDrop.AttachedObjectives.First()));
Assert.Equal(NodeState.UNKNOWN, optional.State);
Assert.Empty(fakePossibilities[1].DroppedFromObjectives);
Assert.Empty(parent.DroppedPossibilities);
Assert.True(objective.TryDropPossibility(fakePossibilities[1].AttachedObjectives.First()));
Assert.Equal(NodeState.DROPPED, optional.State);
Assert.Empty(fakePossibilities[1].DroppedFromObjectives);
Assert.Single(parent.DroppedPossibilities, linkToParent);
objective.ReturnPossibility(fakePossibilities[1].AttachedObjectives.First());
Assert.Equal(NodeState.UNKNOWN, optional.State);
Assert.Empty(fakePossibilities[1].DroppedFromObjectives);
Assert.Empty(parent.DroppedPossibilities);
objective.ReturnPossibility(childToDrop.AttachedObjectives.First());
Assert.Equal(NodeState.UNKNOWN, optional.State);
Assert.Empty(fakePossibilities[1].DroppedFromObjectives);
Assert.Empty(parent.DroppedPossibilities);
}
public void TryDropAndReturnFromObjective_CascadesToOtherParents_DropsThenReturns()
{
var fakePossibilities = new FakePossibility[] {
new FakePossibility(),
new FakePossibility(),
};
var childOptional = OptionalObjective.CreateWithPossibilities(
Possibilities.CreatePossibilities(new(), 2), 1);
var optional = OptionalObjective.CreateWithPossibilities(
fakePossibilities.Cast <IPossibility>().Prepend(childOptional).ToArray(), 1);
var parentToDropFrom = OptionalObjective.CreateWithPossibilities(
new IPossibility[] {
new FakePossibility(),
}, 1);
var linkToParent = Link.CreateConnectedLink(optional, parentToDropFrom);
var parentToCascadeDrop = OptionalObjective.CreateWithPossibilities(
new IPossibility[] {
new FakePossibility(),
optional,
}, 2);
var required = new FakeObjective(isRequired: true);
Link.CreateConnectedLink(parentToDropFrom, required);
Link.CreateConnectedLink(parentToCascadeDrop, required);
IPossibility possibility = optional;
Assert.True(possibility.TryDropFromObjective(linkToParent));
Assert.Equal(NodeState.DROPPED, optional.State);
Assert.Equal(NodeState.DROPPED, parentToCascadeDrop.State);
possibility.ReturnFromObjective(linkToParent);
Assert.Equal(NodeState.UNKNOWN, optional.State);
Assert.Equal(NodeState.UNKNOWN, parentToCascadeDrop.State);
}
public void TrySelectPossibility_WhenRejectedByParent_LeavesUnchanged()
{
var fakePossibilities = new FakePossibility[] {
new FakePossibility(),
new FakePossibility(),
};
var childOptional = OptionalObjective.CreateWithPossibilities(
Possibilities.CreatePossibilities(new(), 2), 1);
var optional = OptionalObjective.CreateWithPossibilities(fakePossibilities, 1);
var linkToChildOptional = Link.CreateConnectedLink(childOptional, optional);
var parent = new FakeObjective(isRequired: true);
parent.CanSelectPossibilities = false;
var linkToParent = Link.CreateConnectedLink(optional, parent);
IPossibility possibility = optional;
IObjective objective = optional;
Assert.False(objective.TrySelectPossibility(fakePossibilities[0].AttachedObjectives.First()));
Assert.Equal(NodeState.UNKNOWN, optional.State);
Assert.Equal(NodeState.UNKNOWN, childOptional.State);
Assert.All(((IObjective)childOptional).GetUnknownDirectPossibilities().Cast <Possibility>(),
p => Assert.Equal(NodeState.UNKNOWN, p.State));
Assert.Empty(fakePossibilities[0].DroppedFromObjectives);
Assert.Empty(fakePossibilities[1].DroppedFromObjectives);
Assert.Empty(parent.SelectedPossibilities);
}
internal static Link CreateConnectedLink(IPossibility possibility, IObjective objective)
{
var link = new Link(possibility, objective);
possibility.AppendObjective(link);
objective.AppendPossibility(link);
return(link);
}
public void TrySelectAndDeselectPossibility_Succeeds()
{
var fakePossibilities = new FakePossibility[] {
new FakePossibility(),
new FakePossibility(),
};
var childOptional = OptionalObjective.CreateWithPossibilities(
Possibilities.CreatePossibilities(new(), 2), 1);
var optional = OptionalObjective.CreateWithPossibilities(fakePossibilities, 2);
var linkToChildOptional = Link.CreateConnectedLink(childOptional, optional);
var parent = new FakeObjective(isRequired: true);
var linkToParent = Link.CreateConnectedLink(optional, parent);
IPossibility possibility = optional;
IObjective objective = optional;
Assert.True(objective.TrySelectPossibility(fakePossibilities[0].AttachedObjectives.First()));
Assert.Equal(NodeState.UNKNOWN, optional.State);
Assert.Equal(NodeState.UNKNOWN, childOptional.State);
Assert.All(((IObjective)childOptional).GetUnknownDirectPossibilities().Cast <Possibility>(),
p => Assert.Equal(NodeState.UNKNOWN, p.State));
Assert.Empty(fakePossibilities[0].DroppedFromObjectives);
Assert.Empty(fakePossibilities[1].DroppedFromObjectives);
Assert.Empty(parent.SelectedPossibilities);
Assert.True(objective.TrySelectPossibility(fakePossibilities[1].AttachedObjectives.First()));
Assert.Equal(NodeState.SELECTED, optional.State);
Assert.Equal(NodeState.UNKNOWN, childOptional.State);
Assert.All(((IObjective)childOptional).GetUnknownDirectPossibilities().Cast <Possibility>(),
p => Assert.Equal(NodeState.UNKNOWN, p.State));
Assert.Single(parent.SelectedPossibilities, linkToParent);
Assert.Empty(fakePossibilities[0].DroppedFromObjectives);
Assert.Empty(fakePossibilities[1].DroppedFromObjectives);
objective.DeselectPossibility(fakePossibilities[1].AttachedObjectives.First());
Assert.Equal(NodeState.UNKNOWN, optional.State);
Assert.Equal(NodeState.UNKNOWN, childOptional.State);
Assert.All(((IObjective)childOptional).GetUnknownDirectPossibilities().Cast <Possibility>(),
p => Assert.Equal(NodeState.UNKNOWN, p.State));
Assert.Empty(fakePossibilities[0].DroppedFromObjectives);
Assert.Empty(fakePossibilities[1].DroppedFromObjectives);
Assert.Empty(parent.SelectedPossibilities);
objective.DeselectPossibility(fakePossibilities[0].AttachedObjectives.First());
Assert.Equal(NodeState.UNKNOWN, optional.State);
Assert.Equal(NodeState.UNKNOWN, childOptional.State);
Assert.All(((IObjective)childOptional).GetUnknownDirectPossibilities().Cast <Possibility>(),
p => Assert.Equal(NodeState.UNKNOWN, p.State));
Assert.Empty(fakePossibilities[0].DroppedFromObjectives);
Assert.Empty(fakePossibilities[1].DroppedFromObjectives);
Assert.Empty(parent.SelectedPossibilities);
}
public void AllUnknownPossibilitiesAreConcrete_UpdatesWhenPossibilitiesChange()
{
var puzzle = new Puzzle(4);
var matrix = ExactCoverGraph.Create(puzzle);
var fakePossibility = new FakePossibility(isConcrete: false);
var possibilities = new IPossibility[] {
new Possibility(new Coordinate(), 0),
fakePossibility,
};
var objective = Objective.CreateFullyConnected(matrix, possibilities, 1);
Assert.Single(fakePossibility.AttachedObjectives);
Assert.False(objective.AllUnknownPossibilitiesAreConcrete);
Assert.True(((IObjective)objective).TryDropPossibility(fakePossibility.AttachedObjectives.First()));
Assert.True(objective.AllUnknownPossibilitiesAreConcrete);
}
public void TrySelectAndDeselect_WhenSharedByOpposingObjectives_Fails()
{
var puzzle = new Puzzle(4);
var matrix = ExactCoverGraph.Create(puzzle);
var concretePossibility = new Possibility(new(), 1);
var possibilities = new IPossibility[] { concretePossibility };
var parentA = OptionalObjective.CreateWithPossibilities(possibilities, 1);
var parentB = OptionalObjective.CreateWithPossibilities(possibilities.Append(new FakePossibility()).ToArray(), 1);
var required = Objective.CreateFullyConnected(
matrix,
new IPossibility[] { parentA, parentB },
1);
Assert.False(concretePossibility.TrySelect());
Assert.Equal(NodeState.UNKNOWN, parentA.State);
Assert.Equal(NodeState.UNKNOWN, parentB.State);
Assert.NotEqual(NodeState.SELECTED, required.State);
}
public void TryDetachAndReattachObjective_IfRequiredObjective_DropsThenReturns()
{
var concretePossibility = new Possibility(new(), 1);
IPossibility possibility = concretePossibility;
var objective = new FakeObjective();
var objectiveToDetach = new FakeObjective(isRequired: true);
var linkToDrop = Link.CreateConnectedLink(possibility, objective);
var linkToDetach = Link.CreateConnectedLink(possibility, objectiveToDetach);
Assert.True(possibility.TryDropFromObjective(linkToDetach));
Assert.Equal(NodeState.DROPPED, concretePossibility.State);
Assert.Single(objective.DroppedPossibilities, linkToDrop);
Assert.Empty(objectiveToDetach.DroppedPossibilities);
possibility.ReturnFromObjective(linkToDetach);
Assert.Equal(NodeState.UNKNOWN, concretePossibility.State);
Assert.Empty(objective.DroppedPossibilities);
Assert.Empty(objectiveToDetach.DroppedPossibilities);
}
public void TryDetach_CausingDrop_IfDropDisallowed_LeavesUnchanged()
{
var concretePossibility = new Possibility(new(), 1);
IPossibility possibility = concretePossibility;
var objective = new FakeObjective(isRequired: true);
objective.CanDropPossibilities = false;
var objectiveToDetach = new FakeObjective(isRequired: true);
Link linkToOther = Link.CreateConnectedLink(possibility, objective);
Link linkToDetach = Link.CreateConnectedLink(possibility, objectiveToDetach);
Assert.False(possibility.TryDropFromObjective(linkToDetach));
Assert.Equal(NodeState.UNKNOWN, concretePossibility.State);
Assert.Empty(objective.DroppedPossibilities);
Assert.Empty(objectiveToDetach.DroppedPossibilities);
// Verify the attempted-detached objective was still attached by dropping the
// possibility from it.
Assert.True(possibility.TryDropFromObjective(linkToOther));
Assert.Equal(NodeState.DROPPED, concretePossibility.State);
Assert.Single(objectiveToDetach.DroppedPossibilities, linkToDetach);
}
public void TryDropFromObjective_LeavesPossibilitiesUnchanged()
{
var fakePossibilities = new FakePossibility[] {
new FakePossibility(),
new FakePossibility(),
};
var childOptional = OptionalObjective.CreateWithPossibilities(
Possibilities.CreatePossibilities(new(), 2), 1);
var optional = OptionalObjective.CreateWithPossibilities(
fakePossibilities.Cast <IPossibility>().Prepend(childOptional).ToArray(), 1);
var parent = new FakeObjective(isRequired: true);
var linkToParent = Link.CreateConnectedLink(optional, parent);
IPossibility possibility = optional;
IObjective objective = optional;
Assert.True(possibility.TryDropFromObjective(linkToParent));
Assert.Equal(NodeState.DROPPED, optional.State);
Assert.Equal(NodeState.UNKNOWN, childOptional.State);
Assert.All(((IObjective)childOptional).GetUnknownDirectPossibilities().Cast <Possibility>(),
p => Assert.Equal(NodeState.UNKNOWN, p.State));
Assert.Empty(parent.SelectedPossibilities);
Assert.Empty(fakePossibilities[0].DroppedFromObjectives);
Assert.Empty(fakePossibilities[1].DroppedFromObjectives);
}
private Link(IPossibility possibility, IObjective objective)
{
Possibility = possibility;
Objective = objective;
PreviousOnObjective = NextOnObjective = NextOnPossibility = PreviousOnPossibility = this;
}
