Replace Condition with a simple Func<bool>

since that's all it now encapsulates; noone uses the optional `success`
action delegate anymore.

src/Moq/Language/Flow/WhenPhrase.cs

@@ -10,9 +10,9 @@ internal sealed class WhenPhrase<T> : ISetupConditionResult<T>
 		where T : class
 	{
 		private Mock<T> mock;
-		private Condition condition;
+		private Func<bool> condition;
 
-		public WhenPhrase(Mock<T> mock, Condition condition)
+		public WhenPhrase(Mock<T> mock, Func<bool> condition)
 		{
 			this.mock = mock;
 			this.condition = condition;

src/Moq/MethodCall.cs

@@ -22,12 +22,12 @@ internal sealed partial class MethodCall : SetupWithOutParameterSupport
 		private Behavior raiseEvent;
 		private Behavior returnOrThrow;
 		private Behavior afterReturnCallback;
-		private Condition condition;
+		private Func<bool> condition;
 		private string failMessage;
 
 		private string declarationSite;
 
-		public MethodCall(Expression originalExpression, Mock mock, Condition condition, InvocationShape expectation)
+		public MethodCall(Expression originalExpression, Mock mock, Func<bool> condition, InvocationShape expectation)
 			: base(originalExpression, mock, expectation)
 		{
 			this.condition = condition;
@@ -43,7 +43,7 @@ public string FailMessage
 			get => this.failMessage;
 		}
 
-		public override Condition Condition => this.condition;
+		public override Func<bool> Condition => this.condition;
 
 		private static string GetUserCodeCallSite()
 		{

src/Moq/Mock.Generic.cs

@@ -712,7 +712,7 @@ public ISetupSequentialAction SetupSequence(Expression<Action<T>> expression)
 		/// </param>
 		public ISetupConditionResult<T> When(Func<bool> condition)
 		{
-			return new WhenPhrase<T>(this, new Condition(condition));
+			return new WhenPhrase<T>(this, condition);
 		}
 
 #endregion

src/Moq/Mock.cs

@@ -515,7 +515,7 @@ private static void VerifyNoOtherCalls(Mock mock, HashSet<Mock> verifiedMocks)
 
 		#region Setup
 
-		internal static MethodCall Setup(Mock mock, LambdaExpression expression, Condition condition)
+		internal static MethodCall Setup(Mock mock, LambdaExpression expression, Func<bool> condition)
 		{
 			Guard.NotNull(expression, nameof(expression));
 
@@ -527,7 +527,7 @@ internal static MethodCall Setup(Mock mock, LambdaExpression expression, Conditi
 			});
 		}
 
-		internal static MethodCall SetupGet(Mock mock, LambdaExpression expression, Condition condition)
+		internal static MethodCall SetupGet(Mock mock, LambdaExpression expression, Func<bool> condition)
 		{
 			Guard.NotNull(expression, nameof(expression));
 
@@ -540,7 +540,7 @@ internal static MethodCall SetupGet(Mock mock, LambdaExpression expression, Cond
 			return Mock.Setup(mock, expression, condition);
 		}
 
-		internal static MethodCall SetupSet(Mock mock, LambdaExpression expression, Condition condition)
+		internal static MethodCall SetupSet(Mock mock, LambdaExpression expression, Func<bool> condition)
 		{
 			Guard.NotNull(expression, nameof(expression));
 			Guard.IsAssignmentToPropertyOrIndexer(expression, nameof(expression));
@@ -580,15 +580,15 @@ internal static void SetupSet(Mock mock, LambdaExpression expression, PropertyIn
 			}, allowNonOverridableLastProperty: true);
 		}
 
-		internal static MethodCall SetupAdd(Mock mock, LambdaExpression expression, Condition condition)
+		internal static MethodCall SetupAdd(Mock mock, LambdaExpression expression, Func<bool> condition)
 		{
 			Guard.NotNull(expression, nameof(expression));
 			Guard.IsEventAdd(expression, nameof(expression));
 
 			return Mock.Setup(mock, expression, condition);
 		}
 
-		internal static MethodCall SetupRemove(Mock mock, LambdaExpression expression, Condition condition)
+		internal static MethodCall SetupRemove(Mock mock, LambdaExpression expression, Func<bool> condition)
 		{
 			Guard.NotNull(expression, nameof(expression));
 			Guard.IsEventRemove(expression, nameof(expression));

src/Moq/Setup.cs

@@ -29,7 +29,7 @@ protected Setup(Expression originalExpression, Mock mock, InvocationShape expect
 			this.mock = mock;
 		}
 
-		public virtual Condition Condition => null;
+		public virtual Func<bool> Condition => null;
 
 		public InvocationShape Expectation => this.expectation;
 
@@ -61,8 +61,7 @@ public void Execute(Invocation invocation)
 			invocation.MarkAsMatchedBy(this);
 			this.SetOutParameters(invocation);
 
-			// update condition (important for `MockSequence`) and matchers (important for `Capture`):
-			this.Condition?.SetupEvaluatedSuccessfully();
+			// update matchers (important for `Capture`):
 			this.expectation.SetupEvaluatedSuccessfully(invocation);
 
 			this.ExecuteCore(invocation);
@@ -99,7 +98,7 @@ public void MarkAsVerifiable()
 
 		public bool Matches(Invocation invocation)
 		{
-			return this.expectation.IsMatch(invocation) && (this.Condition == null || this.Condition.IsTrue);
+			return this.expectation.IsMatch(invocation) && (this.Condition == null || this.Condition());
 		}
 
 		public virtual void SetOutParameters(Invocation invocation)