fix: BaseEntity finder methods to properly typecheck lazy relations c…

…onditions (#5710)

Co-authored-by: Umed Khudoiberdiev <pleerock.me@gmail.com>

src/find-options/FindConditions.ts

@@ -3,6 +3,13 @@ import {FindOperator} from "./FindOperator";
 /**
  * Used for find operations.
  */
-export type FindConditions<T> = {
-    [P in keyof T]?: FindConditions<T[P]> | FindOperator<FindConditions<T[P]>>;
+export type FindCondition<T> = FindConditions<T> | FindOperator<FindConditions<T>>;
+
+/**
+ * Used for find operations.
+ */
+export type FindConditions<T> = T | {
+    [P in keyof T]?: T[P] extends Promise<infer U>
+        ? FindCondition<U>
+        : FindCondition<T[P]>;
 };

test/functional/relations/lazy-relations/lazy-relations-loading-via-base-entitiy-finders/entity/Category.ts

@@ -0,0 +1,20 @@
+import {Entity} from "../../../../../../src/decorator/entity/Entity";
+import {PrimaryGeneratedColumn} from "../../../../../../src/decorator/columns/PrimaryGeneratedColumn";
+import {Column} from "../../../../../../src/decorator/columns/Column";
+import {Post} from "./Post";
+import {OneToMany} from "../../../../../../src/decorator/relations/OneToMany";
+import { BaseEntity } from "../../../../../../src";
+
+@Entity()
+export class Category extends BaseEntity {
+
+    @PrimaryGeneratedColumn()
+    id: number;
+
+    @Column()
+    name: string;
+
+    @OneToMany(() => Post, post => post.category)
+    posts: Promise<Post[]>;
+
+}

test/functional/relations/lazy-relations/lazy-relations-loading-via-base-entitiy-finders/entity/Post.ts

@@ -0,0 +1,21 @@
+import {Entity} from "../../../../../../src/decorator/entity/Entity";
+import {PrimaryGeneratedColumn} from "../../../../../../src/decorator/columns/PrimaryGeneratedColumn";
+import {Column} from "../../../../../../src/decorator/columns/Column";
+import {Category} from "./Category";
+import {ManyToOne} from "../../../../../../src/decorator/relations/ManyToOne";
+import {BaseEntity} from "../../../../../../src";
+
+@Entity()
+export class Post extends BaseEntity {
+
+    @PrimaryGeneratedColumn()
+    id: number;
+
+    @Column()
+    title: string;
+
+    @ManyToOne(() => Category, category => category.posts, {
+        cascade: ["insert"]
+    })
+    category: Promise<Category>;
+}

test/functional/relations/lazy-relations/lazy-relations-loading-via-base-entitiy-finders/index.ts

@@ -0,0 +1,34 @@
+import {Post} from "./entity/Post";
+import {Category} from "./entity/Category";
+import "reflect-metadata";
+import {closeTestingConnections, createTestingConnections, reloadTestingDatabases} from "../../../../utils/test-utils";
+import {Connection} from "../../../../../src/connection/Connection";
+import {expect} from "chai";
+import {PromiseUtils} from "../../../../../src";
+
+describe("lazy-relations-loading-via-base-entity-finders", () => {
+
+    let connections: Connection[];
+    before(async () => connections = await createTestingConnections({
+        entities: [__dirname + "/entity/*{.js,.ts}"],
+        // we can properly test lazy-relations only on one platform
+        enabledDrivers: ["mysql"]
+    }));
+
+    beforeEach(() => reloadTestingDatabases(connections));
+    after(() => closeTestingConnections(connections));
+
+    it("works", () => PromiseUtils.runInSequence(connections, async connection =>  {
+        Category.useConnection(connection);
+        Post.useConnection(connection);
+        const category = new Category();
+        category.name = "hello";
+        await category.save();
+        const post = new Post();
+        post.title = "hello post";
+        post.category = Promise.resolve(category);
+        await post.save();
+        expect((await Post.findOneOrFail({category})).id).equal(post.id);
+        expect((await Post.findOneOrFail({category: {id: category.id}})).id).equal(post.id);
+    }));
+});