fix(core): do not mutate data provided to em.upsert/Many

Closes #5136

packages/core/src/EntityManager.ts

@@ -642,6 +642,7 @@ export class EntityManager<D extends IDatabaseDriver = IDatabaseDriver> {
       where = helper(entity).getPrimaryKey() as FilterQuery<Entity>;
       data = em.comparator.prepareEntity(entity);
     } else {
+      data = Utils.copy(data);
       where = Utils.extractPK(data, meta) as FilterQuery<Entity>;
 
       if (where) {
@@ -785,7 +786,8 @@ export class EntityManager<D extends IDatabaseDriver = IDatabaseDriver> {
     const entities = new Map<Entity, EntityData<Entity>>();
     const entitiesByData = new Map<EntityData<Entity>, Entity>();
 
-    for (let row of data) {
+    for (let i = 0; i < data.length; i++) {
+      let row = data[i];
       let where: FilterQuery<Entity>;
 
       if (Utils.isEntity(row)) {
@@ -801,6 +803,7 @@ export class EntityManager<D extends IDatabaseDriver = IDatabaseDriver> {
         where = helper(entity).getPrimaryKey() as FilterQuery<Entity>;
         row = em.comparator.prepareEntity(entity);
       } else {
+        row = data[i] = Utils.copy(row);
         where = Utils.extractPK(row, meta) as FilterQuery<Entity>;
 
         if (where) {

tests/features/upsert/GH5136.test.ts

@@ -0,0 +1,75 @@
+import { Property, Entity, PrimaryKey } from '@mikro-orm/core';
+import { MikroORM } from '@mikro-orm/sqlite';
+
+@Entity()
+class User {
+
+  @PrimaryKey()
+  id!: number;
+
+  @Property()
+  name: string;
+
+  @Property({ unique: true })
+  email: string;
+
+  constructor(name: string, email: string) {
+    this.name = name;
+    this.email = email;
+  }
+
+}
+
+let orm: MikroORM;
+
+beforeAll(async () => {
+  orm = await MikroORM.init({
+    dbName: ':memory:',
+    entities: [User],
+  });
+  await orm.schema.createSchema();
+});
+
+beforeEach(async () => {
+  await orm.schema.clearDatabase();
+});
+
+afterAll(async () => {
+  await orm.close(true);
+});
+
+test('upsert should not modify data object unless it is an entity', async () => {
+  const data = { name: 'Foo', email: 'foo' };
+  orm.em.create(User, data);
+  await orm.em.flush();
+  orm.em.clear();
+
+  expect(data).toMatchObject({ name: 'Foo', email: 'foo' });
+
+  data.name = 'Bar';
+  const newUser = await orm.em.upsert(User, data);
+
+  expect(data).toMatchObject({ name: 'Bar', email: 'foo' });
+  expect({ name: 'Bar', email: 'foo' }).toMatchObject(data);
+});
+
+test('upsertMany should not modify data object unless it is an entity', async () => {
+  const data1 = { name: 'Foo1', email: 'foo1' };
+  const data2 = { name: 'Foo2', email: 'foo2' };
+  orm.em.create(User, data1);
+  orm.em.create(User, data2);
+  await orm.em.flush();
+  orm.em.clear();
+
+  expect(data1).toMatchObject({ name: 'Foo1', email: 'foo1' });
+  expect(data2).toMatchObject({ name: 'Foo2', email: 'foo2' });
+
+  data1.name = 'Bar1';
+  data2.name = 'Bar2';
+  const [newUser1, newUser2] = await orm.em.upsertMany(User, [data1, data2]);
+
+  expect(data1).toMatchObject({ name: 'Bar1', email: 'foo1' });
+  expect(data2).toMatchObject({ name: 'Bar2', email: 'foo2' });
+  expect({ name: 'Bar1', email: 'foo1' }).toMatchObject(data1);
+  expect({ name: 'Bar2', email: 'foo2' }).toMatchObject(data2);
+});