improve ObjectType.cs coverage

Author: Stepami

src/Domain/HydraScript.Domain.IR/Types/ObjectType.cs

@@ -99,32 +99,14 @@ private class ObjectTypeHasher
         public ObjectTypeHasher(ObjectType reference) =>
             _reference = reference;
 
-        private int Hash(Type type) => type switch
-        {
-            ArrayType arrayType => HashArrayType(arrayType),
-            ObjectType objectType => HashObjectType(objectType),
-            NullableType nullableType => HashNullableType(nullableType),
-            _ => type.GetHashCode()
-        };
-
         public int HashObjectType(ObjectType objectType) =>
             objectType._properties.Keys.Select(
                     key => HashCode.Combine(
                         key,
                         objectType[key]!.Equals(_reference)
                             ? "@this".GetHashCode()
-                            : objectType[key]!.GetType().GetHashCode()))
+                            : HashCode.Combine(key, objectType[key]!.GetType())))
                 .Aggregate(36, HashCode.Combine);
-
-        private int HashArrayType(ArrayType arrayType) =>
-            arrayType.Type.Equals(_reference)
-                ? "@this".GetHashCode()
-                : Hash(arrayType.Type);
-
-        private int HashNullableType(NullableType nullableType) =>
-            nullableType.Type.Equals(_reference)
-                ? "@this".GetHashCode()
-                : Hash(nullableType.Type);
     }
 
     private class ObjectTypePrinter

tests/HydraScript.IntegrationTests/Samples/this.js

@@ -2,6 +2,8 @@ type ObjType = {
     num: number;
     flag: boolean;
     str: string;
+    arr: number[];
+    nullableFlag: boolean?;
 }
 
 function toString(obj: ObjType): string {
@@ -13,6 +15,8 @@ let obj: ObjType = {
     num: 1;
     flag: true;
     str: "field";
+    arr: [1, 2, 3];
+    nullableFlag: null;
 }
 
 >>> obj.toString()