Introduce base class for predicates

src/Polly.Core.Tests/Polly.Core.Tests.csproj

@@ -16,6 +16,6 @@
   </ItemGroup>
 
   <ItemGroup>
-    <Using Include="Polly.Core.Tests.Utils"/>
+    <Using Include="Polly.Core.Tests.Utils" />
   </ItemGroup>
 </Project>

src/Polly.Core.Tests/Retry/RetryStrategyOptionsTests.cs

@@ -0,0 +1,15 @@
+using Polly.Retry;
+
+namespace Polly.Core.Tests.Retry;
+
+public class RetryStrategyOptionsTests
+{
+    [Fact]
+    public void Ctor_Ok()
+    {
+        var options = new RetryStrategyOptions();
+
+        options.ShouldRetry.Should().NotBeNull();
+        options.ShouldRetry.IsEmpty.Should().BeTrue();
+    }
+}

src/Polly.Core.Tests/Retry/ShouldRetryArgumentsTests.cs

@@ -0,0 +1,15 @@
+using Polly.Retry;
+
+namespace Polly.Core.Tests.Retry;
+public class ShouldRetryArgumentsTests
+{
+    [Fact]
+    public void Ctor_Ok()
+    {
+        var args = new ShouldRetryArguments(ResilienceContext.Get(), 2, TimeSpan.FromSeconds(2));
+
+        args.Context.Should().NotBeNull();
+        args.AttemptNumber.Should().Be(2);
+        args.TotalExecutionTime.Should().Be(TimeSpan.FromSeconds(2));
+    }
+}

src/Polly.Core.Tests/Strategy/OutcomePredicateTests.cs

@@ -0,0 +1,334 @@
+using System;
+using System.Threading.Tasks;
+using Polly.Strategy;
+
+namespace Polly.Core.Tests.Strategy;
+
+public class OutcomePredicateTests
+{
+    private readonly DummyPredicate _sut = new();
+
+    [Fact]
+    public void Empty_Ok()
+    {
+        _sut.IsEmpty.Should().BeTrue();
+
+        _sut.Exception<Exception>();
+
+        _sut.IsEmpty.Should().BeFalse();
+    }
+
+    [Fact]
+    public void CreateHandler_Empty_ReturnsNull()
+    {
+        _sut.CreateHandler().Should().BeNull();
+    }
+
+    public static readonly TheoryData<Action<DummyPredicate>> ExceptionPredicates = new()
+    {
+        sut =>
+        {
+            sut.Exception<InvalidOperationException>();
+            InvokeHandler(sut, new InvalidOperationException("dummy"), true);
+        },
+        sut =>
+        {
+            sut.Exception<InvalidOperationException>(_=> true);
+            InvokeHandler(sut, new ArgumentNullException("dummy"), false);
+        },
+        sut =>
+        {
+            sut.Exception<InvalidOperationException>((_, _)=> true);
+            InvokeHandler(sut, new ArgumentNullException("dummy"), false);
+        },
+        sut =>
+        {
+            sut.Exception<InvalidOperationException>((_, _)=> new ValueTask<bool>(true));
+            InvokeHandler(sut, new ArgumentNullException("dummy"), false);
+        },
+        sut =>
+        {
+            sut.Exception<InvalidOperationException>();
+            InvokeHandler(sut, new ArgumentNullException("dummy"), false);
+        },
+        sut =>
+        {
+            sut.Exception<InvalidOperationException>();
+            InvokeHandler(sut, new InvalidOperationException("dummy"), true);
+        },
+        sut =>
+        {
+            sut.Exception<InvalidOperationException>(e => e.Message.Contains("dummy"));
+            InvokeHandler(sut, new InvalidOperationException("other message"), false);
+        },
+        sut =>
+        {
+            sut.Exception<InvalidOperationException>((e, _) => e.Message.Contains("dummy"));
+            InvokeHandler(sut, new InvalidOperationException("other message"), false);
+        },
+        sut =>
+        {
+            sut.Exception<InvalidOperationException>((e, _) => e.Message.Contains("dummy"));
+            InvokeHandler(sut, new InvalidOperationException("dummy"), true);
+        },
+        sut =>
+        {
+            sut.Exception<InvalidOperationException>((e, _) => new ValueTask<bool>(e.Message.Contains("dummy")));
+            InvokeHandler(sut, new InvalidOperationException("other message"), false);
+        },
+        sut =>
+        {
+            sut.Exception<InvalidOperationException>((e, _) => new ValueTask<bool>(e.Message.Contains("dummy")));
+            InvokeHandler(sut, new InvalidOperationException("dummy"), true);
+        },
+    };
+
+    [MemberData(nameof(ExceptionPredicates))]
+    [Theory]
+    public void ExceptionHandler_SinglePredicate_Ok(Action<DummyPredicate> execute)
+    {
+        _sut.Invoking(s => execute(s)).Should().NotThrow();
+        execute(_sut);
+    }
+
+    [MemberData(nameof(ExceptionPredicates))]
+    [Theory]
+    public void ExceptionHandler_MultiplePredicates_Ok(Action<DummyPredicate> execute)
+    {
+        _sut.Exception<Exception>(e => false);
+        _sut.Invoking(s => execute(s)).Should().NotThrow();
+    }
+
+    public static readonly TheoryData<Action<DummyPredicate>> ResultPredicates = new()
+    {
+        sut =>
+        {
+            sut.Result(10);
+            InvokeResultHandler(sut, 10, true);
+        },
+        sut =>
+        {
+            sut.Result(11);
+            InvokeResultHandler(sut, 10, false);
+        },
+        sut =>
+        {
+            sut.Result(10);
+            InvokeResultHandler(sut, 10.0, false);
+        },
+        sut =>
+        {
+            sut.Result<int>(result => result == 5);
+            InvokeResultHandler(sut, 5, true);
+        },
+        sut =>
+        {
+            sut.Result<int>(result => result == 5);
+            InvokeResultHandler(sut, 6, false);
+        },
+        sut =>
+        {
+            sut.Result<int>((result, _) => result == 5);
+            InvokeResultHandler(sut, 5, true);
+        },
+        sut =>
+        {
+            sut.Result<int>((result, _) => result == 5);
+            InvokeResultHandler(sut, 6, false);
+        },
+        sut =>
+        {
+            sut.Result<int>((result, _) => new ValueTask<bool>(result == 5));
+            InvokeResultHandler(sut, 5, true);
+        },
+        sut =>
+        {
+            sut.Result<int>((result, _) => new ValueTask<bool>(result == 5));
+            InvokeResultHandler(sut, 6, false);
+        },
+        sut =>
+        {
+            sut.Result(10);
+            sut.Result(11);
+            sut.Result("dummy-1");
+            sut.Result("dummy-2");
+
+            InvokeResultHandler(sut, "dummy", false);
+            InvokeResultHandler(sut, "dummy-1", true);
+            InvokeResultHandler(sut, "dummy-2", true);
+
+            InvokeResultHandler(sut, 10, true);
+            InvokeResultHandler(sut, 11, true);
+            InvokeResultHandler(sut, 12, false);
+
+            InvokeResultHandler(sut, new object(), false);
+        },
+        sut =>
+        {
+            sut.Outcome<int>((outcome, _) => new ValueTask<bool>(outcome.Result == 5));
+            InvokeResultHandler(sut, 6, false);
+        },
+        sut =>
+        {
+            sut.Outcome<int>((outcome, _) => new ValueTask<bool>(outcome.Result == 6));
+            InvokeResultHandler(sut, 6, true);
+        },
+        sut =>
+        {
+            sut.Outcome<int>((outcome, _) => outcome.Result == 5);
+            InvokeResultHandler(sut, 6, false);
+        },
+        sut =>
+        {
+            sut.Outcome<int>((outcome, _) => outcome.Result == 6);
+            InvokeResultHandler(sut, 6, true);
+        },
+        sut =>
+        {
+            sut.Result<int>((result, _) => result == 6);
+            InvokeHandler(sut, new InvalidOperationException(), false);
+            InvokeHandler<int>(sut, new InvalidOperationException(), false);
+        },
+        sut =>
+        {
+            sut.Result<int>((result, _) => new ValueTask<bool>(result == 6));
+            InvokeHandler(sut, new InvalidOperationException(), false);
+            InvokeHandler<int>(sut, new InvalidOperationException(), false);
+        },
+        sut =>
+        {
+            sut.Outcome<int>((outcome, _) => outcome.Exception is InvalidOperationException);
+            InvokeHandler<int>(sut, new InvalidOperationException(), true);
+        },
+        sut =>
+        {
+            sut.Outcome<int>((outcome, _) => new ValueTask<bool>(outcome.Exception is InvalidOperationException));
+            InvokeHandler<int>(sut, new InvalidOperationException(), true);
+        }
+    };
+
+    [MemberData(nameof(ResultPredicates))]
+    [Theory]
+    public void ResultHandler_SinglePredicate_Ok(Action<DummyPredicate> executeResult)
+    {
+        _sut.Invoking(s => executeResult(s)).Should().NotThrow();
+        executeResult(_sut);
+    }
+
+    [MemberData(nameof(ResultPredicates))]
+    [Theory]
+    public void ResultHandler_MultiplePredicates_Ok(Action<DummyPredicate> executeResult)
+    {
+        _sut.Exception<Exception>(e => false);
+        _sut.Invoking(s => executeResult(s)).Should().NotThrow();
+    }
+
+    [InlineData(true)]
+    [InlineData(false)]
+    [Theory]
+    public void AddResultHandlers_Multiple(bool differentTypes)
+    {
+        var callbacks = new List<int>();
+
+        for (var i = 0; i < 10; i++)
+        {
+            var index = i;
+
+            _sut.Result<int>(result =>
+            {
+                callbacks.Add(index);
+                return false;
+            });
+
+            if (differentTypes)
+            {
+                _sut.Result<string>(result =>
+                {
+                    callbacks.Add(index);
+                    return false;
+                });
+            }
+        }
+
+        InvokeResultHandler(_sut, 10, false);
+        callbacks.Distinct().Should().HaveCount(10);
+    }
+
+    [Fact]
+    public void AddResultHandlers_DifferentResultType_NotInvoked()
+    {
+        var callbacks = new List<int>();
+
+        for (var i = 0; i < 10; i++)
+        {
+            var index = i;
+
+            _sut.Result<int>(result =>
+            {
+                callbacks.Add(index);
+                return false;
+            });
+        }
+
+        InvokeResultHandler(_sut, new object(), false);
+
+        callbacks.Distinct().Should().HaveCount(0);
+    }
+
+    [Fact]
+    public void AddResultHandlers_StopOnTrue()
+    {
+        var callbacks = new List<int>();
+
+        for (var i = 0; i < 10; i++)
+        {
+            var index = i;
+
+            _sut.Result<int>(result =>
+            {
+                callbacks.Add(index);
+                return index > 5;
+            });
+        }
+
+        InvokeResultHandler(_sut, 1, true);
+        callbacks.Distinct().Should().HaveCount(7);
+    }
+
+    private static void InvokeHandler<TResult>(DummyPredicate sut, Exception exception, bool expectedResult)
+    {
+        var args = new Args();
+        sut.CreateHandler()!.ShouldHandle(new Outcome<TResult>(exception), args).AsTask().Result.Should().Be(expectedResult);
+    }
+
+    private static void InvokeHandler(DummyPredicate sut, Exception exception, bool expectedResult)
+    {
+        var args = new Args();
+
+        sut.CreateHandler()!.ShouldHandle(new Outcome<object>(exception), args).AsTask().Result.Should().Be(expectedResult);
+
+        // again with void result
+        sut.CreateHandler()!.ShouldHandle(new Outcome<VoidResult>(exception), args).AsTask().Result.Should().Be(expectedResult);
+
+        // again with result
+        sut.Result(12345);
+        sut.CreateHandler()!.ShouldHandle(new Outcome<int>(10), args).AsTask().Result.Should().Be(false);
+    }
+
+    private static void InvokeResultHandler<T>(DummyPredicate sut, T result, bool expectedResult)
+    {
+        var args = new Args();
+        sut.CreateHandler()!.ShouldHandle<T>(new Outcome<T>(result), args).AsTask().Result.Should().Be(expectedResult);
+    }
+
+    public sealed class DummyPredicate : OutcomePredicate<Args, DummyPredicate>
+    {
+    }
+
+    public class Args : IResilienceArguments
+    {
+        public Args() => Context = ResilienceContext.Get();
+
+        public ResilienceContext Context { get; private set; }
+    }
+}