public IGen <Test> ForAPositiveRoot_ItShrinksToTheLocalMinimum() =>
from localMin in Gen.Int64().GreaterThanEqual(0)
from root in Gen.Int64().GreaterThanEqual(localMin)
select Property.ForThese(() =>
{
var exampleSpace = ExampleSpaceFactory.Int64(root, 0, long.MinValue, long.MaxValue);
var path = exampleSpace
.ExploreCounterexamples(x => x < localMin)
.Where(x => x.IsCounterexample())
.Select(x => x.Value());
path.Should().EndWith(localMin);
});
public IGen <Test> ForANegativeRoot_ItShrinksToTheLocalMaximum() =>
from localMax in Gen.Int64().LessThan(0).GreaterThan(int.MinValue)
from root in Gen.Int64().LessThan(localMax)
select Property.ForThese(() =>
{
var exampleSpace = ExampleSpaceFactory.Int64(root, 0, long.MinValue, long.MaxValue);
var path = exampleSpace
.ExploreCounterexamples(x => x > localMax)
.Where(x => x.IsCounterexample())
.Select(x => x.Value());
path.Last().Should().Be(localMax);
});
public IGen <Test> ItShrinksToTheOrigin() =>
from origin in Gen.Int64()
from root in Gen.Int64()
select Property.ForThese(() =>
{
var exampleSpace = ExampleSpaceFactory.Int64(root, origin, long.MinValue, long.MaxValue);
var path = exampleSpace
.ExploreCounterexamples(x => false)
.Where(x => x.IsCounterexample())
.Select(x => x.Value());
path.Should().EndWith(origin);
});