Fixes App-vNext#2299

Adds logic handling a case when the value being requested is null

src/Polly.Core/ResilienceProperties.cs

@@ -20,10 +20,18 @@ public sealed class ResilienceProperties
  /// <returns>True, if a property was retrieved.</returns>
  public bool TryGetValue<TValue>(ResiliencePropertyKey<TValue> key, [MaybeNullWhen(false)] out TValue value)
  {
- if (Options.TryGetValue(key.Key, out object? val) && val is TValue typedValue)
+ if (Options.TryGetValue(key.Key, out object? val))
  {
- value = typedValue;
- return true;
+ if (val is TValue typedValue)
+ {
+ value = typedValue;
+ return true;
+ }
+ else if (val == null)
+ {
+ value = default!;
+ return true;
+ }
  }
 
  value = default;

test/Polly.Core.Tests/ResiliencePropertiesTests.cs

@@ -14,6 +14,18 @@ public void TryGetValue_Ok()
  val.Should().Be(12345);
  }
 
+ [Fact]
+ public void TryGetValue_ValueIsNull_Ok()
+ {
+ var key = new ResiliencePropertyKey<string?>("dummy");
+ var props = new ResilienceProperties();
+
+ props.Set(key, null);
+
+ props.TryGetValue(key, out var val).Should().Be(true);
+ val.Should().Be(null);
+ }
+
  [Fact]
  public void TryGetValue_NotFound_Ok()
  {
@@ -34,6 +46,17 @@ public void GetValue_Ok()
  props.GetValue(key, default).Should().Be(12345);
  }
 
+ [Fact]
+ public void GetValue_ValueIsNull_Ok()
+ {
+ var key = new ResiliencePropertyKey<string?>("dummy");
+ var props = new ResilienceProperties();
+
+ props.Set(key, null);
+
+ props.GetValue(key, "default").Should().Be(null);
+ }
+
  [Fact]
  public void GetValue_NotFound_EnsureDefault()
  {