Merge branch 'main' into remove-some-redundant-async-state-machines-

src/Polly.Benchmarks/Cache.cs

@@ -66,7 +66,7 @@ public MemoryCacheProvider(IMemoryCache memoryCache)
             _cache = memoryCache;
         }
 
-        public (bool, object) TryGet(string key)
+        public (bool, object?) TryGet(string key)
         {
             bool cacheHit = _cache.TryGetValue(key, out var value);
             return (cacheHit, value);
@@ -96,7 +96,7 @@ public void Put(string key, object value, Ttl ttl)
             _cache.Set(key, value, options);
         }
 
-        public Task<(bool, object)> TryGetAsync(string key, CancellationToken cancellationToken, bool continueOnCapturedContext)
+        public Task<(bool, object?)> TryGetAsync(string key, CancellationToken cancellationToken, bool continueOnCapturedContext)
         {
             return Task.FromResult(TryGet(key));
         }

src/Polly.Benchmarks/Polly.Benchmarks.csproj

@@ -1,13 +1,13 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <IsPackable>false</IsPackable>
-    <LangVersion>latest</LangVersion>
     <OutputType>Exe</OutputType>
     <TargetFramework>net6.0</TargetFramework>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
   <ItemGroup>
     <PackageReference Include="BenchmarkDotNet" Version="0.13.3" />
-    <PackageReference Include="Microsoft.Extensions.Caching.Memory" Version="6.0.1" />
+    <PackageReference Include="Microsoft.Extensions.Caching.Memory" Version="7.0.0" />
   </ItemGroup>
   <ItemGroup Condition=" '$(BenchmarkFromNuGet)' != 'True' ">
     <ProjectReference Include="..\Polly\Polly.csproj" />

src/Polly.Benchmarks/Workloads.cs

@@ -30,21 +30,23 @@ internal static async Task ActionInfiniteAsync(CancellationToken cancellationTok
         }
     }
 
-    internal static T Func<T>() => default;
+    internal static T Func<T>()
+        where T : struct
+        => default;
 
-    internal static Task<T> FuncAsync<T>() => Task.FromResult<T>(default);
+    internal static Task<T> FuncAsync<T>()
+        where T : struct
+        => Task.FromResult<T>(default);
 
-    internal static Task<T> FuncAsync<T>(CancellationToken cancellationToken) => Task.FromResult<T>(default);
+    internal static Task<T> FuncAsync<T>(CancellationToken cancellationToken)
+        where T : struct
+        => Task.FromResult<T>(default);
 
     internal static TResult FuncThrows<TResult, TException>()
         where TException : Exception, new()
-    {
-        throw new TException();
-    }
+        => throw new TException();
 
     internal static Task<TResult> FuncThrowsAsync<TResult, TException>()
         where TException : Exception, new()
-    {
-        throw new TException();
-    }
-}
+        => throw new TException();
+}

src/Polly.Specs/Bulkhead/BulkheadTResultAsyncSpecs.cs

@@ -62,7 +62,7 @@ public async Task Should_call_onBulkheadRejected_with_passed_context()
         Func<Context, Task> onRejectedAsync = async ctx => { contextPassedToOnRejected = ctx; await TaskHelper.EmptyTask; };
 
         using (var bulkhead = Policy.BulkheadAsync<int>(1, onRejectedAsync))
-        { 
+        {
             TaskCompletionSource<object> tcs = new TaskCompletionSource<object>();
             using (CancellationTokenSource cancellationSource = new CancellationTokenSource())
             {

src/Polly.Specs/Bulkhead/BulkheadTResultSpecs.cs

@@ -62,7 +62,7 @@ public void Should_call_onBulkheadRejected_with_passed_context()
         Action<Context> onRejected = ctx => { contextPassedToOnRejected = ctx; };
 
         using (BulkheadPolicy<int> bulkhead = Policy.Bulkhead<int>(1, onRejected))
-        { 
+        {
             TaskCompletionSource<object> tcs = new TaskCompletionSource<object>();
             using (CancellationTokenSource cancellationSource = new CancellationTokenSource())
             {

src/Polly.Specs/Caching/SerializingCacheProviderAsyncSpecs.cs

@@ -11,7 +11,7 @@ namespace Polly.Specs.Caching;
 
 public class AsyncSerializingCacheProviderSpecs
 {
-    #region Object-to-TSerialized serializer 
+    #region Object-to-TSerialized serializer
 
     [Fact]
     public void Single_generic_constructor_should_throw_on_no_wrapped_cache_provider()

src/Polly.Specs/Caching/SerializingCacheProviderSpecs.cs

@@ -9,7 +9,7 @@ namespace Polly.Specs.Caching;
 
 public class SerializingCacheProviderSpecs
 {
-    #region Object-to-TSerialized serializer 
+    #region Object-to-TSerialized serializer
 
     [Fact]
     public void Single_generic_constructor_should_throw_on_no_wrapped_cache_provider()

src/Polly.Specs/CircuitBreaker/AdvancedCircuitBreakerSpecs.cs

@@ -82,9 +82,9 @@ public void Should_throw_if_timeslice_duration_is_less_than_resolution_of_circui
         Action action = () => Policy
             .Handle<DivideByZeroException>()
             .AdvancedCircuitBreaker(
-                0.5, 
-                TimeSpan.FromMilliseconds(20).Add(TimeSpan.FromTicks(-1)), 
-                4, 
+                0.5,
+                TimeSpan.FromMilliseconds(20).Add(TimeSpan.FromTicks(-1)),
+                4,
                 TimeSpan.FromSeconds(30));
 
         action.Should().Throw<ArgumentOutOfRangeException>()
@@ -164,8 +164,8 @@ public void Should_initialise_to_closed_state()
 
     #region Tests that are independent from health metrics implementation
 
-    // Tests on the AdvancedCircuitBreaker operation typically use a breaker: 
-    // - with a failure threshold of >=50%, 
+    // Tests on the AdvancedCircuitBreaker operation typically use a breaker:
+    // - with a failure threshold of >=50%,
     // - and a throughput threshold of 4
     // - across a ten-second period.
     // These provide easy values for testing for failure and throughput thresholds each being met and non-met, in combination.
@@ -244,8 +244,8 @@ public void Should_not_open_circuit_if_exceptions_raised_are_not_one_of_the_spec
 
     #region With sample duration higher than 199 ms so that multiple windows are used
 
-    // Tests on the AdvancedCircuitBreaker operation typically use a breaker: 
-    // - with a failure threshold of >=50%, 
+    // Tests on the AdvancedCircuitBreaker operation typically use a breaker:
+    // - with a failure threshold of >=50%,
     // - and a throughput threshold of 4
     // - across a ten-second period.
     // These provide easy values for testing for failure and throughput thresholds each being met and non-met, in combination.
@@ -838,8 +838,8 @@ public void Should_not_open_circuit_if_failures_at_end_of_last_timeslice_and_fai
         // Setting the time to just barely into the new timeslice
         SystemClock.UtcNow = () => time.Add(samplingDuration);
 
-        // A third failure occurs just at the beginning of the new timeslice making 
-        // the number of failures above the failure threshold. However, the throughput is 
+        // A third failure occurs just at the beginning of the new timeslice making
+        // the number of failures above the failure threshold. However, the throughput is
         // below the minimum threshold as to open the circuit.
         breaker.Invoking(x => x.RaiseException<DivideByZeroException>())
             .Should().Throw<DivideByZeroException>();
@@ -898,8 +898,8 @@ public void Should_open_circuit_if_failures_in_second_window_of_last_timeslice_a
 
     #region With sample duration at 199 ms so that only a single window is used
 
-    // These tests on AdvancedCircuitBreaker operation typically use a breaker: 
-    // - with a failure threshold of >=50%, 
+    // These tests on AdvancedCircuitBreaker operation typically use a breaker:
+    // - with a failure threshold of >=50%,
     // - and a throughput threshold of 4
     // - across a 199ms period.
     // These provide easy values for testing for failure and throughput thresholds each being met and non-met, in combination.
@@ -1258,7 +1258,7 @@ public void Should_not_open_circuit_if_failures_at_end_of_last_timeslice_below_f
         // Setting the time to just barely into the new timeslice
         SystemClock.UtcNow = () => time.Add(samplingDuration);
 
-        // This failure does not open the circuit, because a new duration should have 
+        // This failure does not open the circuit, because a new duration should have
         // started and with such low sampling duration, windows should not be used.
         breaker.Invoking(x => x.RaiseException<DivideByZeroException>())
             .Should().Throw<DivideByZeroException>();
@@ -1413,7 +1413,7 @@ public void Should_open_circuit_again_after_the_specified_duration_has_passed_if
         breaker.Invoking(x => x.RaiseException<DivideByZeroException>())
             .Should().Throw<DivideByZeroException>();
         breaker.CircuitState.Should().Be(CircuitState.Open);
-      
+
     }
 
     [Fact]
@@ -1483,7 +1483,7 @@ public void Should_only_allow_single_execution_on_first_entering_halfopen_state_
         breaker.Invoking(x => x.RaiseException<DivideByZeroException>())
             .Should().Throw<DivideByZeroException>();
 
-        // exception raised, circuit is now open.  
+        // exception raised, circuit is now open.
         breaker.CircuitState.Should().Be(CircuitState.Open);
 
         // break duration passes, circuit now half open
@@ -1522,7 +1522,7 @@ public void Should_allow_single_execution_per_break_duration_in_halfopen_state__
         breaker.Invoking(x => x.RaiseException<DivideByZeroException>())
             .Should().Throw<DivideByZeroException>();
 
-        // exception raised, circuit is now open.  
+        // exception raised, circuit is now open.
         breaker.CircuitState.Should().Be(CircuitState.Open);
 
         // break duration passes, circuit now half open
@@ -1569,7 +1569,7 @@ public void Should_only_allow_single_execution_on_first_entering_halfopen_state_
         breaker.Invoking(x => x.RaiseException<DivideByZeroException>())
             .Should().Throw<DivideByZeroException>();
 
-        // exceptions raised, circuit is now open.  
+        // exceptions raised, circuit is now open.
         breaker.CircuitState.Should().Be(CircuitState.Open);
 
         // break duration passes, circuit now half open
@@ -1582,7 +1582,7 @@ public void Should_only_allow_single_execution_on_first_entering_halfopen_state_
         TimeSpan testTimeoutToExposeDeadlocks = TimeSpan.FromSeconds(5);
         using (ManualResetEvent permitSecondExecutionAttempt = new ManualResetEvent(false))
         using (ManualResetEvent permitFirstExecutionEnd = new ManualResetEvent(false))
-        { 
+        {
             bool? firstDelegateExecutedInHalfOpenState = null;
             bool? secondDelegateExecutedInHalfOpenState = null;
             bool? secondDelegateRejectedInHalfOpenState = null;
@@ -1642,7 +1642,7 @@ public void Should_only_allow_single_execution_on_first_entering_halfopen_state_
             firstExecution.Status.Should().Be(TaskStatus.RanToCompletion);
             secondExecution.Status.Should().Be(TaskStatus.RanToCompletion);
 
-            // Assert: 
+            // Assert:
             // - First execution should have been permitted and executed under a HalfOpen state
             // - Second overlapping execution in halfopen state should not have been permitted.
             // - Second execution attempt should have been rejected with HalfOpen state as cause.
@@ -1674,7 +1674,7 @@ public void Should_allow_single_execution_per_break_duration_in_halfopen_state__
         breaker.Invoking(x => x.RaiseException<DivideByZeroException>())
             .Should().Throw<DivideByZeroException>();
 
-        // exception raised, circuit is now open.  
+        // exception raised, circuit is now open.
         breaker.CircuitState.Should().Be(CircuitState.Open);
 
         // break duration passes, circuit now half open
@@ -1688,7 +1688,7 @@ public void Should_allow_single_execution_per_break_duration_in_halfopen_state__
         TimeSpan testTimeoutToExposeDeadlocks = TimeSpan.FromSeconds(5);
         using (ManualResetEvent permitSecondExecutionAttempt = new ManualResetEvent(false))
         using (ManualResetEvent permitFirstExecutionEnd = new ManualResetEvent(false))
-        { 
+        {
             bool? firstDelegateExecutedInHalfOpenState = null;
             bool? secondDelegateExecutedInHalfOpenState = null;
             bool? secondDelegateRejectedInHalfOpenState = null;
@@ -1750,7 +1750,7 @@ public void Should_allow_single_execution_per_break_duration_in_halfopen_state__
             firstExecution.Status.Should().Be(TaskStatus.RanToCompletion);
             secondExecution.Status.Should().Be(TaskStatus.RanToCompletion);
 
-            // Assert: 
+            // Assert:
             // - First execution should have been permitted and executed under a HalfOpen state
             // - Second overlapping execution in halfopen state should have been permitted, one breakDuration later.
             firstDelegateExecutedInHalfOpenState.Should().BeTrue();
@@ -1997,7 +1997,7 @@ public void Should_call_onbreak_when_breaking_circuit_first_time_but_not_for_sub
 
         onBreakCalled.Should().Be(1);
 
-        // call through circuit when already broken - should not retrigger onBreak 
+        // call through circuit when already broken - should not retrigger onBreak
         breaker.Invoking(x => x.RaiseException<DivideByZeroException>())
             .Should().Throw<BrokenCircuitException>();
 
@@ -2491,7 +2491,7 @@ public void Should_open_circuit_with_timespan_maxvalue_if_manual_override_open()
 
         var time = 1.January(2000);
         SystemClock.UtcNow = () => time;
-        
+
         CircuitBreakerPolicy breaker = Policy
             .Handle<DivideByZeroException>()
             .AdvancedCircuitBreaker(

src/Polly.Specs/CircuitBreaker/CircuitBreakerAsyncSpecs.cs

@@ -324,7 +324,7 @@ public async Task Should_only_allow_single_execution_on_first_entering_halfopen_
         await breaker.Awaiting(x => x.RaiseExceptionAsync<DivideByZeroException>())
               .Should().ThrowAsync<DivideByZeroException>();
 
-        // exception raised, circuit is now open.  
+        // exception raised, circuit is now open.
         breaker.CircuitState.Should().Be(CircuitState.Open);
 
         // break duration passes, circuit now half open
@@ -355,13 +355,13 @@ public async Task Should_allow_single_execution_per_break_duration_in_halfopen_s
         await breaker.Awaiting(x => x.RaiseExceptionAsync<DivideByZeroException>())
               .Should().ThrowAsync<DivideByZeroException>();
 
-        // exception raised, circuit is now open.  
+        // exception raised, circuit is now open.
         breaker.CircuitState.Should().Be(CircuitState.Open);
 
         // break duration passes, circuit now half open
         SystemClock.UtcNow = () => time.Add(durationOfBreak);
         breaker.CircuitState.Should().Be(CircuitState.HalfOpen);
-        
+
 
         // OnActionPreExecute() should permit first execution.
         breaker._breakerController.Invoking(c => c.OnActionPreExecute()).Should().NotThrow();
@@ -394,7 +394,7 @@ public async Task Should_only_allow_single_execution_on_first_entering_halfopen_
         await breaker.Awaiting(x => x.RaiseExceptionAsync<DivideByZeroException>())
               .Should().ThrowAsync<DivideByZeroException>();
 
-        // exception raised, circuit is now open.  
+        // exception raised, circuit is now open.
         breaker.CircuitState.Should().Be(CircuitState.Open);
 
         // break duration passes, circuit now half open
@@ -469,7 +469,7 @@ await breaker.ExecuteAsync(async () =>
             firstExecution.Status.Should().Be(TaskStatus.RanToCompletion);
             secondExecution.Status.Should().Be(TaskStatus.RanToCompletion);
 
-            // Assert: 
+            // Assert:
             // - First execution should have been permitted and executed under a HalfOpen state
             // - Second overlapping execution in halfopen state should not have been permitted.
             // - Second execution attempt should have been rejected with HalfOpen state as cause.
@@ -493,7 +493,7 @@ public async Task Should_allow_single_execution_per_break_duration_in_halfopen_s
         await breaker.Awaiting(x => x.RaiseExceptionAsync<DivideByZeroException>())
               .Should().ThrowAsync<DivideByZeroException>();
 
-        // exception raised, circuit is now open.  
+        // exception raised, circuit is now open.
         breaker.CircuitState.Should().Be(CircuitState.Open);
 
         // break duration passes, circuit now half open
@@ -571,7 +571,7 @@ await breaker.ExecuteAsync(async () =>
             firstExecution.Status.Should().Be(TaskStatus.RanToCompletion);
             secondExecution.Status.Should().Be(TaskStatus.RanToCompletion);
 
-            // Assert: 
+            // Assert:
             // - First execution should have been permitted and executed under a HalfOpen state
             // - Second overlapping execution in halfopen state should have been permitted, one breakDuration later.
             firstDelegateExecutedInHalfOpenState.Should().BeTrue();
@@ -772,7 +772,7 @@ await breaker.Awaiting(x => x.RaiseExceptionAsync<DivideByZeroException>())
         breaker.CircuitState.Should().Be(CircuitState.Open);
         onBreakCalled.Should().Be(1);
 
-        // call through circuit when already broken - should not retrigger onBreak 
+        // call through circuit when already broken - should not retrigger onBreak
         await breaker.Awaiting(x => x.RaiseExceptionAsync<DivideByZeroException>())
               .Should().ThrowAsync<BrokenCircuitException>();