fix: save does not return id, save does not return generated (#7336)

* fix save does not return id

* allow subject.generatedMap to be null/undefined

* stop using coalescing operator

* actually allow generated map to bu undefined

* add test

* use doublequotes

* remove singlequotes

* fix formatting

src/persistence/SubjectExecutor.ts

@@ -428,15 +428,19 @@ export class SubjectExecutor {
                 }
 
                 const updateResult = await updateQueryBuilder.execute();
-                subject.generatedMap = updateResult.generatedMaps[0];
-                if (subject.generatedMap) {
+                let updateGeneratedMap = updateResult.generatedMaps[0];
+                if (updateGeneratedMap) {
                     subject.metadata.columns.forEach(column => {
-                        const value = column.getEntityValue(subject.generatedMap!);
+                        const value = column.getEntityValue(updateGeneratedMap!);
                         if (value !== undefined && value !== null) {
                             const preparedValue = this.queryRunner.connection.driver.prepareHydratedValue(value, column);
-                            column.setEntityValue(subject.generatedMap!, preparedValue);
+                            column.setEntityValue(updateGeneratedMap!, preparedValue);
                         }
                     });
+                    if (!subject.generatedMap) {
+                        subject.generatedMap = {};
+                    }
+                    Object.assign(subject.generatedMap, updateGeneratedMap);
                 }
 
                 // experiments, remove probably, need to implement tree tables children removal

test/github-issues/5520/entity/TestChild.ts

@@ -0,0 +1,9 @@
+import { Column, Entity, PrimaryGeneratedColumn } from "../../../../src";
+
+@Entity()
+export class TestChild {
+    @Column()
+    public value: string;
+    @PrimaryGeneratedColumn("uuid")
+    public uuid: string;
+}

test/github-issues/5520/entity/TestParent.ts

@@ -0,0 +1,15 @@
+import { Entity, JoinColumn, OneToOne, PrimaryGeneratedColumn } from "../../../../src";
+import { TestChild } from "./TestChild";
+
+@Entity()
+export class TestParent {
+    @OneToOne("TestChild", {
+        nullable: true,
+        eager: true,
+        cascade: true,
+    })
+    @JoinColumn()
+    public child: TestChild;
+    @PrimaryGeneratedColumn("uuid")
+    public uuid: string;
+}

test/github-issues/5520/issue-5520.ts

@@ -0,0 +1,45 @@
+import "reflect-metadata";
+
+import { assert } from "chai";
+
+import { Connection } from "../../../src";
+import { closeTestingConnections, createTestingConnections, reloadTestingDatabases } from "../../utils/test-utils";
+import { TestChild } from "./entity/TestChild";
+import { TestParent } from "./entity/TestParent";
+
+describe("github issues > #5520 save does not return generated id if object to save contains a many to one relationship with an undefined id", () => {
+    let connections: Connection[];
+    before(
+        async () =>
+            (connections = await createTestingConnections({
+                entities: [__dirname + "/entity/*{.js,.ts}"],
+                schemaCreate: true,
+                dropSchema: true,
+            }))
+    );
+    beforeEach(() => reloadTestingDatabases(connections));
+    after(() => closeTestingConnections(connections));
+
+    it("should generate parents and childs uuid and return them", () =>
+        Promise.all(
+            connections.map(async (connection) => {
+                let entity = new TestParent();
+                let entityChild = new TestChild();
+                entityChild.value = "test";
+                entity.child = entityChild;
+
+                let response = await connection
+                    .getRepository(TestParent)
+                    .save(entity);
+
+                assert(
+                    response.uuid,
+                    "parent uuid should be generated and set"
+                );
+                assert(
+                    response.child.uuid,
+                    "child uuid should be generated and set"
+                );
+            })
+        ));
+});