feat: add basic tests

.eslintrc.js

@@ -5,7 +5,8 @@ module.exports = {
     },
     "extends": [
         "standard-with-typescript",
-        "plugin:prettier/recommended"
+        "plugin:prettier/recommended",
+        'plugin:jest/recommended'
     ],
     "overrides": [
         {

.gitignore

@@ -1,6 +1,6 @@
 **/node_modules
 **/dist
-/coverage
+**/coverage
 /temp
 /tests/**/temp
 /tests/generated-entities

examples/graphql/src/index.ts

@@ -68,7 +68,7 @@ void (async () => {
           // return await author.books.load();
           // return await author.books.load({ dataloader: true });
           // return await em.find(Book, { author: author.id });
-          return entityDataLoader.find(Book, { author: author.id });
+          return await entityDataLoader.find(Book, { author: author.id });
         },
       },
     },

package.json

@@ -7,6 +7,7 @@
   ],
   "scripts": {
     "build": "yarn workspace mikro-orm-find-dataloader run build",
+    "test": "yarn workspace mikro-orm-find-dataloader run test",
     "version": "yarn changeset version && yarn install --immutable",
     "release": "yarn run compile && yarn changeset publish"
   },
@@ -22,18 +23,22 @@
     "@changesets/changelog-github": "^0.4.8",
     "@changesets/cli": "^2.26.2",
     "@types/eslint": "^8.44.7",
+    "@types/jest": "^29.5.8",
     "@types/node": "^20.9.1",
     "@typescript-eslint/eslint-plugin": "^6.11.0",
     "eslint": "^8.54.0",
     "eslint-config-prettier": "^9.0.0",
     "eslint-config-standard-with-typescript": "^40.0.0",
     "eslint-plugin-import": "^2.29.0",
+    "eslint-plugin-jest": "^27.6.0",
     "eslint-plugin-n": "^16.3.1",
     "eslint-plugin-prettier": "^5.0.1",
     "eslint-plugin-promise": "^6.1.1",
+    "jest": "^29.7.0",
     "nodemon": "^3.0.1",
     "prettier": "^3.1.0",
     "rimraf": "^5.0.5",
+    "ts-jest": "^29.1.1",
     "ts-node": "^10.9.1",
     "typescript": "^5.2.2"
   }

packages/find/package.json

@@ -32,13 +32,21 @@
   "scripts": {
     "build": "yarn clean && yarn compile",
     "clean": "yarn run -T rimraf ./dist",
-    "compile": "yarn run -T tsc"
+    "compile": "yarn run -T tsc",
+    "test": "yarn run -T jest"
+  },
+  "jest": {
+    "testEnvironment": "node",
+    "preset": "ts-jest",
+    "collectCoverage": true,
+    "testPathIgnorePatterns": ["/node_modules/", "/dist/"]
   },
   "publishConfig": {
     "access": "public"
   },
   "devDependencies": {
-    "@mikro-orm/core": "6.0.0-dev.187"
+    "@mikro-orm/core": "6.0.0-dev.187",
+    "@mikro-orm/sqlite": "6.0.0-dev.187"
   },
   "peerDependencies": {
     "@mikro-orm/core": "^6.0.0"

packages/find/src/__snapshots__/find.test.ts.snap

@@ -0,0 +1,44 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`find should fetch books with the find dataloader 1`] = `
+[
+  [
+    {
+      "author": 1,
+      "id": 1,
+      "title": "One",
+    },
+    {
+      "author": 1,
+      "id": 2,
+      "title": "Two",
+    },
+  ],
+  [
+    {
+      "author": 2,
+      "id": 3,
+      "title": "Three",
+    },
+  ],
+  [
+    {
+      "author": 3,
+      "id": 4,
+      "title": "Four",
+    },
+    {
+      "author": 3,
+      "id": 5,
+      "title": "Five",
+    },
+    {
+      "author": 3,
+      "id": 6,
+      "title": "Six",
+    },
+  ],
+  [],
+  [],
+]
+`;

packages/find/src/find.test.ts

@@ -0,0 +1,125 @@
+/* eslint-disable @typescript-eslint/no-non-null-assertion */
+import {
+  type SqlEntityManager,
+  MikroORM,
+  Entity,
+  PrimaryKey,
+  Property,
+  Collection,
+  OneToMany,
+  Ref,
+  ref,
+  ManyToOne,
+} from "@mikro-orm/sqlite";
+import { EntityDataLoader } from "./EntityDataLoader";
+
+@Entity()
+class Author {
+  @PrimaryKey()
+  id!: number;
+
+  @Property()
+  name: string;
+
+  @OneToMany(() => Book, (book) => book.author)
+  books = new Collection<Book>(this);
+
+  constructor({ id, name }: { id?: number; name: string }) {
+    if (id != null) {
+      this.id = id;
+    }
+    this.name = name;
+  }
+}
+
+@Entity()
+class Book {
+  @PrimaryKey()
+  id!: number;
+
+  @Property()
+  title: string;
+
+  @ManyToOne(() => Author, { ref: true })
+  author: Ref<Author>;
+
+  constructor({ id, title, author }: { id?: number; title: string; author: Author | Ref<Author> }) {
+    if (id != null) {
+      this.id = id;
+    }
+    this.title = title;
+    this.author = ref(author);
+  }
+}
+
+async function populateDatabase(em: MikroORM["em"]): Promise<void> {
+  const authors = [
+    new Author({ id: 1, name: "a" }),
+    new Author({ id: 2, name: "b" }),
+    new Author({ id: 3, name: "c" }),
+    new Author({ id: 4, name: "d" }),
+    new Author({ id: 5, name: "e" }),
+  ];
+  em.persist(authors);
+
+  const books = [
+    new Book({ id: 1, title: "One", author: authors[0]! }),
+    new Book({ id: 2, title: "Two", author: authors[0]! }),
+    new Book({ id: 3, title: "Three", author: authors[1]! }),
+    new Book({ id: 4, title: "Four", author: authors[2]! }),
+    new Book({ id: 5, title: "Five", author: authors[2]! }),
+    new Book({ id: 6, title: "Six", author: authors[2]! }),
+  ];
+  em.persist(books);
+  await em.flush();
+}
+
+describe("find", () => {
+  let orm: MikroORM;
+  let emFork: SqlEntityManager;
+  let dataloader: EntityDataLoader;
+
+  beforeAll(async () => {
+    orm = await MikroORM.init({
+      dbName: ":memory:",
+      entities: [Author, Book],
+    });
+    try {
+      await orm.schema.clearDatabase();
+    } catch {}
+    try {
+      const generator = orm.getSchemaGenerator();
+      await generator.createSchema({ wrap: true });
+    } catch {}
+    await populateDatabase(orm.em.fork());
+  });
+
+  beforeEach(async () => {
+    emFork = orm.em.fork();
+    dataloader = new EntityDataLoader(orm.em.fork());
+  });
+
+  it("should fetch books with the find dataloader", async () => {
+    const authors = await emFork.find(Author, {});
+    const authorBooks = await Promise.all(authors.map(async ({ id }) => await dataloader.find(Book, { author: id })));
+    expect(authorBooks).toBeDefined();
+    expect(authorBooks).toMatchSnapshot();
+  });
+
+  it("should return the same books as find", async () => {
+    const authors = await emFork.find(Author, {});
+    const dataloaderBooks = await Promise.all(
+      authors.map(async ({ id }) => await dataloader.find(Book, { author: id })),
+    );
+    const findBooks = await Promise.all(authors.map(async ({ id }) => await emFork.find(Book, { author: id })));
+    expect(dataloaderBooks.map((res) => res.map(({ id }) => id))).toEqual(
+      findBooks.map((res) => res.map(({ id }) => id)),
+    );
+  });
+
+  afterEach(async () => {});
+
+  afterAll(async () => {
+    await orm.close(true);
+  });
+});