fix(core): fix folder-based discovery for multiple entities in single…

… file (#5464)

packages/core/src/metadata/MetadataDiscovery.ts

@@ -267,9 +267,8 @@ export class MetadataDiscovery {
           continue;
         }
 
-        this.metadata.set(name, Utils.copy(MetadataStorage.getMetadata(name, path), false));
         const entity = this.prepare(target) as Constructor<AnyEntity>;
-        const schema = this.getSchema(entity);
+        const schema = this.getSchema(entity, path);
         const meta = schema.init().meta;
         this.metadata.set(meta.className, meta);
 
@@ -323,18 +322,23 @@ export class MetadataDiscovery {
       return entity.schema;
     }
 
+    if (EntitySchema.REGISTRY.has(entity)) {
+      return EntitySchema.REGISTRY.get(entity)!;
+    }
+
     return entity as EntityClass<T>;
   }
 
-  private getSchema<T>(entity: Constructor<T> | EntitySchema<T>): EntitySchema<T> {
+  private getSchema<T>(entity: Constructor<T> | EntitySchema<T>, filepath?: string): EntitySchema<T> {
     if (entity instanceof EntitySchema) {
+      if (filepath) {
+        // This will initialize global metadata for 'entity.meta.className'
+        const meta = Utils.copy(MetadataStorage.getMetadata(entity.meta.className, filepath), false);
+        this.metadata.set(entity.meta.className, meta);
+      }
       return entity;
     }
 
-    if (EntitySchema.REGISTRY.has(entity)) {
-      return EntitySchema.REGISTRY.get(entity)!;
-    }
-
     const path = (entity as Dictionary).__path;
 
     if (path) {

tests/MikroORM.test.ts

@@ -52,6 +52,20 @@ describe('MikroORM', () => {
     await expect(MikroORM.init({ driver: MongoDriver, dbName: 'test', baseDir: BASE_DIR, entities: ['entities-1', 'entities-2'] })).rejects.toThrow('Duplicate entity names are not allowed: Dup1, Dup2');
   });
 
+  test('should NOT throw when multiple entities in same file were discovered', async () => {
+    const orm = await MikroORM.init({
+      driver: SqliteDriver,
+      dbName: ':memory:',
+      baseDir: BASE_DIR,
+      connect: false,
+      entities: ['complex-entities/**/*.entity.js'],
+      entitiesTs: ['complex-entities/**/*.entity.ts'],
+    });
+
+    expect(orm).toBeInstanceOf(MikroORM);
+    expect(Object.keys(orm.getMetadata().getAll()).sort()).toEqual(['AbstractClass', 'ClassA', 'ClassB']);
+  });
+
   test('should NOT throw when multiple entities with same file name discovered ("checkDuplicateEntities" false)', async () => {
     const ormInitCommandPromise = MikroORM.init({ driver: MongoDriver, dbName: 'test', baseDir: BASE_DIR, entities: ['entities-1', 'entities-2'], discovery: { checkDuplicateEntities: false } });
 

tests/complex-entities/abstract-class.entity.ts

@@ -0,0 +1,26 @@
+import {
+  Entity,
+  Enum, BaseEntity, PrimaryKey,
+} from '@mikro-orm/postgresql';
+
+export enum SomeEnum {
+  CLASS_A = 'class-a',
+  CLASS_B = 'class-b',
+}
+
+@Entity({ discriminatorColumn: 'type', abstract: true })
+export class AbstractClass extends BaseEntity {
+
+  @PrimaryKey()
+  id!: string;
+
+  @Enum(() => SomeEnum)
+  type!: SomeEnum;
+
+}
+
+@Entity({ discriminatorValue: SomeEnum.CLASS_A })
+export class ClassA extends AbstractClass {}
+
+@Entity({ discriminatorValue: SomeEnum.CLASS_B })
+export class ClassB extends AbstractClass {}