feat(flagd): in-process evaluator returns DISABLED reason for disabled flags

Signed-off-by: Jonathan Norris <jonathan.norris@dynatrace.com>

Author: jonathannorris

src/OpenFeature.Providers.Flagd/Resolver/InProcess/JsonEvaluator.cs

@@ -230,8 +230,11 @@ private ResolutionDetails<T> ResolveValue<T>(string flagKey, T defaultValue,
         {
             if ("DISABLED" == flagConfiguration.State)
             {
-                throw new FeatureProviderException(ErrorType.FlagNotFound,
-                    "FLAG_NOT_FOUND: flag '" + flagKey + "' is disabled");
+                return new ResolutionDetails<T>(
+                    flagKey: flagKey,
+                    defaultValue,
+                    reason: Reason.Disabled
+                );
             }
 
             Dictionary<string, object> combinedMetadata = _flagSetMetadata.ToDictionary(

test/OpenFeature.Providers.Flagd.Test/JsonEvaluatorTest.cs

@@ -245,19 +245,28 @@ public void TestJsonEvaluatorDynamicObjectEvaluation()
     }
 
     [Fact]
-    public void TestJsonEvaluatorDisabledBoolEvaluation()
+    public void TestJsonEvaluatorDisabledFlagReturnsDisabledReason()
     {
         _jsonEvaluator.Sync(FlagConfigurationUpdateType.ALL, Utils.flags);
 
-        var attributes = ImmutableDictionary.CreateBuilder<string, Value>();
-        attributes.Add("color", new Value("yellow"));
+        var result = _jsonEvaluator.ResolveBooleanValueAsync("disabledFlag", false);
 
-        var builder = EvaluationContext.Builder();
-        builder
-            .Set("color", "yellow");
+        Assert.False(result.Value);
+        Assert.Equal(Reason.Disabled, result.Reason);
+        Assert.Null(result.Variant);
+    }
 
-        Assert.Throws<FeatureProviderException>(() =>
-            _jsonEvaluator.ResolveBooleanValueAsync("disabledFlag", false, builder.Build()));
+    [Fact]
+    public void TestJsonEvaluatorDisabledFlagIgnoresTargeting()
+    {
+        _jsonEvaluator.Sync(FlagConfigurationUpdateType.ALL, Utils.flags);
+
+        var context = EvaluationContext.Builder().Set("color", "yellow").Build();
+        var result = _jsonEvaluator.ResolveBooleanValueAsync("disabledFlag", false, context);
+
+        Assert.False(result.Value);
+        Assert.Equal(Reason.Disabled, result.Reason);
+        Assert.Null(result.Variant);
     }
 
     [Fact]