Fixes in JsonEnumIntValueConverter and JsonEnumValueConverter for def…

…ault enum values.
spoleto-software · Aug 2, 2024 · 099a765 · 099a765
1 parent e46f6a3
commit 099a765
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Showing 5 changed files with 71 additions and 25 deletions.
diff --git a/src/Spoleto.Common.Tests/JsonHelperTests.cs b/src/Spoleto.Common.Tests/JsonHelperTests.cs
@@ -30,7 +30,7 @@ public void EnumWithJsonEnumValueAttribute()
             // Arrange
             var obj = new TestClass
             {
-                Test = TestEnumValue.Two
+                Test1 = TestEnumValue.Two
             };
 
             // Act
@@ -40,7 +40,7 @@ public void EnumWithJsonEnumValueAttribute()
             // Assert
             Assert.Multiple(() =>
             {
-                Assert.That(fromJson.Test, Is.EqualTo(obj.Test));
+                Assert.That(fromJson.Test1, Is.EqualTo(obj.Test1));
                 Assert.That(json.Contains("T2"), Is.True);
             });
         }
@@ -51,7 +51,8 @@ public void EnumWithNullJsonEnumValueAttribute()
             // Arrange
             var obj = new TestClass
             {
-                Test = TestEnumValue.Null
+                Test1 = TestEnumValue.Null,
+                Test2 = TestEnumValue.Two
             };
 
             // Act
@@ -61,8 +62,11 @@ public void EnumWithNullJsonEnumValueAttribute()
             // Assert
             Assert.Multiple(() =>
             {
-                Assert.That(fromJson.Test, Is.EqualTo(obj.Test));
-                Assert.That(json.Contains("null"), Is.True);
+                Assert.That(fromJson.Test1, Is.EqualTo(obj.Test1));
+                Assert.That(fromJson.Test2, Is.EqualTo(obj.Test2));
+
+                Assert.That(json, Does.Contain("null"));
+                Assert.That(json, Does.Contain("\"T2\""));
             });
         }
 

diff --git a/src/Spoleto.Common.Tests/Objects/TestClass.cs b/src/Spoleto.Common.Tests/Objects/TestClass.cs
@@ -6,7 +6,10 @@ namespace Spoleto.Common.Tests
     public class TestClass
     {
         [JsonConverter(typeof(JsonEnumValueConverter<TestEnumValue>))]
-        public TestEnumValue Test { get; set; }
+        public TestEnumValue Test1 { get; set; }
+
+        [JsonConverter(typeof(JsonEnumValueConverter<TestEnumValue>))]
+        public TestEnumValue Test2 { get; set; }
 
         [JsonConverter(typeof(JsonIntEnumConverter<TestIntEnum>))]
         public TestIntEnum TestIntEnum { get; set; }

diff --git a/src/Spoleto.Common.Tests/Objects/TestEnumValue.cs b/src/Spoleto.Common.Tests/Objects/TestEnumValue.cs
@@ -8,12 +8,12 @@ namespace Spoleto.Common.Tests
     public enum TestEnumValue
     {
         [JsonEnumValue("O1")]
-        One,
+        One = 1,
 
         [JsonEnumValue("T2")]
-        Two,
+        Two = 2,
 
         [JsonEnumValue(null)]
-        Null
+        Null = -1
     }
 }
diff --git a/src/Spoleto.Common/JsonConverters/JsonEnumIntValueConverter.cs b/src/Spoleto.Common/JsonConverters/JsonEnumIntValueConverter.cs
@@ -40,26 +40,44 @@ public override T Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerial
                 }
             }
 
-            throw new JsonException($"Unknown enum element: {value}");
+            if (value == 0)
+            {
+                return default;
+            }
+
+            throw new JsonException($"Unknown enum '{typeof(T).Name}' element: {value}");
         }
 
         public override void Write(Utf8JsonWriter writer, T value, JsonSerializerOptions options)
         {
-            var enumValue = GetEnumValue(value);
-
-            if (enumValue == null)
-                writer.WriteNullValue();
+            if (TryGetEnumValue(value, out var enumValue))
+            {
+                if (enumValue == null)
+                    writer.WriteNullValue();
+                else
+                    writer.WriteNumberValue(enumValue.Value);
+            }
             else
-                writer.WriteNumberValue(enumValue.Value);
+            {
+                writer.WriteNumberValue((int)(object)value);
+            }
         }
 
-        private int? GetEnumValue(Enum value)
+        private bool TryGetEnumValue(Enum value, out int? outValue)
         {
             var field = value.GetType().GetField(value.ToString());
 
-            return field.GetCustomAttribute<JsonEnumIntValueAttribute>() is JsonEnumIntValueAttribute attribute
+            if (field == null)
+            {
+                outValue = null;
+                return false;
+            }
+
+            outValue = field.GetCustomAttribute<JsonEnumIntValueAttribute>() is JsonEnumIntValueAttribute attribute
                 ? attribute.Value
                 : Convert.ToInt32(value);
+
+            return true;
         }
     }
 }
diff --git a/src/Spoleto.Common/JsonConverters/JsonEnumValueConverter.cs b/src/Spoleto.Common/JsonConverters/JsonEnumValueConverter.cs
@@ -19,6 +19,14 @@ public override T Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerial
             {
                 value = null;
             }
+            else if (reader.TokenType == JsonTokenType.Number)
+            {
+                var numValue = reader.GetInt32();
+                if (numValue == 0)
+                    return default;
+
+                throw new JsonException($"Unknown enum '{typeof(T).Name}' element: {numValue}");
+            }
             else
             {
                 value = reader.GetString();
@@ -40,26 +48,39 @@ public override T Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerial
                 }
             }
 
-            throw new JsonException($"Unknown enum element: {value}");
+            throw new JsonException($"Unknown enum '{typeof(T).Name}' element: {value}");
         }
 
         public override void Write(Utf8JsonWriter writer, T value, JsonSerializerOptions options)
         {
-            var enumValue = GetEnumValue(value);
-
-            if (enumValue == null)
-                writer.WriteNullValue();
+            if (TryGetEnumValue(value, out var enumValue))
+            {
+                if (enumValue == null)
+                    writer.WriteNullValue();
+                else
+                    writer.WriteStringValue(enumValue);
+            }
             else
-                writer.WriteStringValue(enumValue);
+            {
+                writer.WriteNumberValue((int)(object)value);
+            }
         }
 
-        private string GetEnumValue(Enum value)
+        private bool TryGetEnumValue(Enum value, out string outValue)
         {
             var field = value.GetType().GetField(value.ToString());
 
-            return field.GetCustomAttribute<JsonEnumValueAttribute>() is JsonEnumValueAttribute attribute
+            if (field == null)
+            {
+                outValue = null;
+                return false;
+            }
+
+            outValue = field.GetCustomAttribute<JsonEnumValueAttribute>() is JsonEnumValueAttribute attribute
                 ? attribute.Value
                 : value.ToString();
+
+            return true;
         }
     }
 }