Mutable tests

src/effect/schema/class/Mutable.ts

@@ -0,0 +1,50 @@
+import { Schema } from "@effect/schema"
+import type { Types } from "effect"
+import type { StaticType } from "../../../StaticType"
+import type { HasFields } from "./util"
+
+
+export interface MutableClass<
+    Self,
+    Fields extends Schema.Struct.Fields,
+    I, R, C,
+    Inherited,
+    Proto,
+>
+extends Omit<
+    StaticType<Schema.Class<Self, Fields, I, R, C, Inherited, Proto>>,
+    "extend"
+>
+{
+    new(
+        ...args: ConstructorParameters<Schema.Class<Self, Fields, I, R, C, Inherited, Proto>>
+    ): Omit<
+        InstanceType<Schema.Class<Self, Fields, I, R, C, Inherited, Proto>>,
+        keyof Fields
+    > &
+    Types.Mutable<Schema.Struct.Type<Fields>>
+
+    extend<Extended>(identifier: string): <newFields extends Schema.Struct.Fields>(
+        fields:        newFields | HasFields<newFields>,
+        annotations?:  Schema.Annotations.Schema<Extended>,
+    ) => MutableClass<
+        Extended,
+        Fields & newFields,
+        I & Schema.Struct.Encoded<newFields>,
+        R | Schema.Struct.Context<newFields>,
+        C & Schema.Struct.Constructor<newFields>,
+        Self,
+        Proto
+    >
+}
+
+
+export const Mutable = <
+    Self,
+    Fields extends Schema.Struct.Fields,
+    I, R, C,
+    Inherited,
+    Proto
+>(
+    self: Schema.Class<Self, Fields, I, R, C, Inherited, Proto>
+) => self as MutableClass<Self, Fields, I, R, C, Inherited, Proto>