using System; using System.Collections; namespace NUnit.Framework.Constraints { public class DictionaryContainsKeyConstraint : CollectionContainsConstraint { public override string DisplayName => "ContainsKey"; public override string Description => "dictionary containing key " + MsgUtils.FormatValue(base.Expected); public DictionaryContainsKeyConstraint(object expected) : base(expected) { } protected override bool Matches(IEnumerable actual) { IDictionary dictionary = actual as IDictionary; if (dictionary == null) throw new ArgumentException("The actual value must be an IDictionary", "actual"); return base.Matches((IEnumerable)dictionary.Keys); } } }