Class models: Enforce extends Realm.Object (#4417)

* Throw if constructors doesn't extend Realm.Object

* Updating existing tests to the breaking change.

* Adding a note to the changelog

CHANGELOG.md

@@ -1,5 +1,8 @@
 x.x.x Release notes (yyyy-MM-dd)
 =============================================================
+### Breaking change
+* Model classes passed as schema to the `Realm` constructor must now extend `Realm.Object`.
+
 ### Enhancements
 * None.
 

integration-tests/tests/src/tests/class-models.ts

@@ -0,0 +1,75 @@
+////////////////////////////////////////////////////////////////////////////
+//
+// Copyright 2022 Realm Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+////////////////////////////////////////////////////////////////////////////
+
+import { expect } from "chai";
+
+import Realm from "realm";
+
+describe("Class models", () => {
+  describe("as schema element", () => {
+    beforeEach(() => {
+      Realm.clearTestState();
+    });
+
+    it("fails without a schema static", () => {
+      class Person extends Realm.Object {}
+      expect(() => {
+        new Realm({ schema: [Person as any] });
+      }).throws("must have a 'schema' property");
+    });
+
+    it("fails without a schema.properties static", () => {
+      class Person extends Realm.Object {
+        static schema = { name: "Person" };
+      }
+      expect(() => {
+        new Realm({ schema: [Person as any] });
+      }).throws("properties must be of type 'object'");
+    });
+
+    it("fails if it doesn't extend Realm.Object", () => {
+      class Person {
+        name!: string;
+        static schema: Realm.ObjectSchema = {
+          name: "Person",
+          properties: { name: "string" },
+        };
+      }
+      expect(() => {
+        new Realm({ schema: [Person as any] });
+      }).throws("Class 'Person' must extend Realm.Object");
+
+      // Mutate the name of the object schema to produce a more detailed error
+      Person.schema.name = "Foo";
+      expect(() => {
+        new Realm({ schema: [Person as any] });
+      }).throws("Class 'Person' (declaring 'Foo' schema) must extend Realm.Object");
+    });
+
+    it("is allowed", () => {
+      class Person extends Realm.Object {
+        name!: string;
+        static schema: Realm.ObjectSchema = {
+          name: "Person",
+          properties: { name: "string" },
+        };
+      }
+      new Realm({ schema: [Person] });
+    });
+  });
+});

integration-tests/tests/src/tests/index.ts

@@ -22,8 +22,9 @@ import chai from "chai";
 chai.use(chaiAsPromised);
 
 import "./realm-constructor";
-import "./serialization";
 import "./objects";
+import "./class-models";
+import "./serialization";
 import "./iterators";
 import "./dynamic-schema-updates";
 import "./bson";

integration-tests/tests/src/tests/serialization.ts

@@ -143,7 +143,7 @@ const testSetups: TestSetup[] = [
     },
   },
   {
-    name: "Class models (NO primaryKey)",
+    name: "Class model (NO primaryKey)",
     schema: [PlaylistNoId, SongNoId],
     testData(realm: Realm) {
       realm.write(() => {
@@ -287,7 +287,7 @@ const testSetups: TestSetup[] = [
     },
   },
   {
-    name: "Class models (Int primaryKey)",
+    name: "Class model (Int primaryKey)",
     schema: [PlaylistWithId, SongWithId],
     testData(realm: Realm) {
       realm.write(() => {

src/js_realm.hpp

@@ -31,6 +31,7 @@
 #include "platform.hpp"
 #include "realm/binary_data.hpp"
 #include <stdexcept>
+#include <string>
 
 #if REALM_ENABLE_SYNC
 #include "js_sync.hpp"
@@ -672,7 +673,26 @@ bool RealmClass<T>::get_realm_config(ContextType ctx, size_t argc, const ValueTy
             ValueType schema_value = Object::get_property(ctx, object, schema_string);
             if (!Value::is_undefined(ctx, schema_value)) {
                 ObjectType schema_array = Value::validated_to_array(ctx, schema_value, "schema");
-                config.schema.emplace(Schema<T>::parse_schema(ctx, schema_array, defaults, constructors));
+                auto schema = Schema<T>::parse_schema(ctx, schema_array, defaults, constructors);
+                // Check that all constructors provided by the user extend Realm.Object
+                const auto& realm_constructor = Value::validated_to_object(ctx, Object::get_global(ctx, "Realm"));
+                const auto& realm_object_constructor = Object::validated_get_object(ctx, realm_constructor, "Object");
+                for (const auto& [name, constructor] : constructors) {
+                    const auto& prototype = Object::get_prototype(ctx, constructor);
+                    if (prototype != realm_object_constructor) {
+                        const std::string& class_name =
+                            Object::validated_get_string(ctx, constructor, "name", "Failed to read class name");
+                        if (class_name == name) {
+                            throw std::invalid_argument(
+                                util::format("Class '%1' must extend Realm.Object", class_name));
+                        }
+                        else {
+                            throw std::invalid_argument(util::format(
+                                "Class '%1' (declaring '%2' schema) must extend Realm.Object", class_name, name));
+                        }
+                    }
+                }
+                config.schema.emplace(std::move(schema));
                 schema_updated = true;
             }
 

tests/js/realm-tests.js

@@ -125,25 +125,7 @@ module.exports = {
     Object.setPrototypeOf(Car2.prototype, Realm.Object.prototype);
     Object.setPrototypeOf(Car2, Realm.Object);
 
-    //test class syntax support without extending Realm.Object
-    let car3ConstructorCalled = false;
-    class Car3 {
-      constructor() {
-        car3ConstructorCalled = true;
-      }
-    }
-
-    Car3.schema = {
-      name: "Car3",
-      properties: {
-        make: "string",
-        model: "string",
-        otherType: { type: "string", mapTo: "type", optional: true },
-        kilometers: { type: "int", default: 0 },
-      },
-    };
-
-    let realm = new Realm({ schema: [Car, Car2, Car3] });
+    let realm = new Realm({ schema: [Car, Car2] });
     realm.write(() => {
       let car = realm.create("Car", { make: "Audi", model: "A4", kilometers: 24 });
       TestCase.assertTrue(constructorCalled);
@@ -181,15 +163,6 @@ module.exports = {
       TestCase.assertEqual(car2_1.model, "Touareg");
       TestCase.assertEqual(car2_1.kilometers, 13);
       TestCase.assertInstanceOf(car2_1, Realm.Object, "car2_1 not an instance of Realm.Object");
-
-      let car3 = realm.create("Car3", { make: "Audi", model: "A4", kilometers: 24 });
-      TestCase.assertTrue(car3ConstructorCalled);
-      TestCase.assertEqual(car3.make, "Audi");
-      TestCase.assertEqual(car3.model, "A4");
-      TestCase.assertEqual(car3.kilometers, 24);
-
-      //methods from Realm.Objects should be present
-      TestCase.assertDefined(car3.addListener);
     });
     realm.close();
   },
@@ -1176,6 +1149,7 @@ module.exports = {
         intCol: "int",
       },
     };
+    Object.setPrototypeOf(CustomObject, Realm.Object);
 
     function InvalidObject() {
       return {};
@@ -1191,6 +1165,7 @@ module.exports = {
         intCol: "int",
       },
     };
+    Object.setPrototypeOf(InvalidObject, Realm.Object);
     let realm = new Realm({ schema: [CustomObject, InvalidObject] });
 
     realm.write(() => {
@@ -1238,6 +1213,7 @@ module.exports = {
         intCol: "int",
       },
     };
+    Object.setPrototypeOf(CustomObject, Realm.Object);
 
     let realm = new Realm({ schema: [CustomObject] });
     realm.write(() => {
@@ -1247,6 +1223,7 @@ module.exports = {
 
     function NewCustomObject() {}
     NewCustomObject.schema = CustomObject.schema;
+    Object.setPrototypeOf(NewCustomObject, Realm.Object);
 
     realm = new Realm({ schema: [NewCustomObject] });
     realm.write(() => {