Improved handling of dictionaries with enum key (#3068)

Do not use dictionary keys for empty enums.
domaindrivendev · Sep 12, 2024 · 09a1282 · 09a1282
1 parent 1c3b099
commit 09a1282
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Showing 3 changed files with 13 additions and 6 deletions.
diff --git a/src/Swashbuckle.AspNetCore.SwaggerGen/SchemaGenerator/SchemaGenerator.cs b/src/Swashbuckle.AspNetCore.SwaggerGen/SchemaGenerator/SchemaGenerator.cs
@@ -350,16 +350,18 @@ private OpenApiSchema CreateArraySchema(DataContract dataContract, SchemaReposit
 
         private OpenApiSchema CreateDictionarySchema(DataContract dataContract, SchemaRepository schemaRepository)
         {
-            if (dataContract.DictionaryKeys != null)
+            var knownKeysProperties = dataContract.DictionaryKeys?.ToDictionary(
+                name => name,
+                _ => GenerateSchema(dataContract.DictionaryValueType, schemaRepository));
+
+            if (knownKeysProperties?.Count > 0)
             {
                 // This is a special case where the set of key values is known (e.g. if the key type is an enum)
                 return new OpenApiSchema
                 {
                     Type = "object",
-                    Properties = dataContract.DictionaryKeys.ToDictionary(
-                        name => name,
-                        name => GenerateSchema(dataContract.DictionaryValueType, schemaRepository)),
-                    AdditionalPropertiesAllowed = false,
+                    Properties = knownKeysProperties,
+                    AdditionalPropertiesAllowed = false
                 };
             }
             else

diff --git a/...shbuckle.AspNetCore.SwaggerGen.Test/SchemaGenerator/JsonSerializerSchemaGeneratorTests.cs b/...shbuckle.AspNetCore.SwaggerGen.Test/SchemaGenerator/JsonSerializerSchemaGeneratorTests.cs
@@ -122,6 +122,7 @@ public void GenerateSchema_DedupsEnumValues_IfEnumTypeHasDuplicateValues()
 
         [Theory]
         [InlineData(typeof(IDictionary<string, int>), "integer")]
+        [InlineData(typeof(IDictionary<EmptyIntEnum, int>), "integer")]
         [InlineData(typeof(IReadOnlyDictionary<string, bool>), "boolean")]
         [InlineData(typeof(IDictionary), null)]
         [InlineData(typeof(ExpandoObject), null)]

diff --git a/test/Swashbuckle.AspNetCore.TestSupport/Fixtures/Enums.cs b/test/Swashbuckle.AspNetCore.TestSupport/Fixtures/Enums.cs
@@ -14,6 +14,10 @@ public enum ShortEnum:short
         Value8 = 8,
     }
 
+    public enum EmptyIntEnum:int
+    {
+    }
+
     public enum IntEnum:int
     {
         Value2 = 2,
@@ -27,4 +31,4 @@ public enum LongEnum:long
         Value4 = 4,
         Value8 = 8,
     }
-}
+}