From 73a8f69d62076750efc8a2fd59292b2d9300e5e8 Mon Sep 17 00:00:00 2001
From: Patrik Oldsberg <poldsberg@gmail.com>
Date: Wed, 14 Dec 2022 11:27:43 +0100
Subject: [PATCH] backend-test-utils: only clean up test backends after all
 tests
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Co-authored-by: Fredrik Adelöw <freben@gmail.com>
Co-authored-by: Johan Haals <johan.haals@gmail.com>
Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>
---
 packages/backend-test-utils/api-report.md     |  2 --
 .../src/next/wiring/TestBackend.test.ts       | 33 ++++++++++++++++++-
 .../src/next/wiring/TestBackend.ts            | 16 ++++-----
 3 files changed, 38 insertions(+), 13 deletions(-)

diff --git a/packages/backend-test-utils/api-report.md b/packages/backend-test-utils/api-report.md
index b791f90726..3df3f3cb21 100644
--- a/packages/backend-test-utils/api-report.md
+++ b/packages/backend-test-utils/api-report.md
@@ -31,8 +31,6 @@ export interface TestBackendOptions<
   TServices extends any[],
   TExtensionPoints extends any[],
 > {
-  // (undocumented)
-  autoStop?: 'afterEach' | 'never';
   // (undocumented)
   extensionPoints?: readonly [
     ...{
diff --git a/packages/backend-test-utils/src/next/wiring/TestBackend.test.ts b/packages/backend-test-utils/src/next/wiring/TestBackend.test.ts
index 417dfa0477..3cc8507df3 100644
--- a/packages/backend-test-utils/src/next/wiring/TestBackend.test.ts
+++ b/packages/backend-test-utils/src/next/wiring/TestBackend.test.ts
@@ -23,6 +23,38 @@ import {
 } from '@backstage/backend-plugin-api';
 import { startTestBackend } from './TestBackend';
 
+// This bit makes sure that test backends are cleaned up properly
+let globalTestBackendHasBeenStopped = false;
+beforeAll(async () => {
+  await startTestBackend({
+    services: [],
+    features: [
+      createBackendModule({
+        moduleId: 'test.module',
+        pluginId: 'test',
+        register(env) {
+          env.registerInit({
+            deps: { lifecycle: coreServices.lifecycle },
+            async init({ lifecycle }) {
+              lifecycle.addShutdownHook({
+                fn() {
+                  globalTestBackendHasBeenStopped = true;
+                },
+              });
+            },
+          });
+        },
+      })(),
+    ],
+  });
+});
+
+afterAll(() => {
+  if (!globalTestBackendHasBeenStopped) {
+    throw new Error('Expected backend to have been stopped');
+  }
+});
+
 describe('TestBackend', () => {
   it('should get a type error if service implementation does not match', async () => {
     type Obj = { a: string; b: string };
@@ -117,7 +149,6 @@ describe('TestBackend', () => {
     const backend = await startTestBackend({
       services: [],
       features: [testModule()],
-      autoStop: 'never',
     });
 
     expect(shutdownSpy).not.toHaveBeenCalled();
diff --git a/packages/backend-test-utils/src/next/wiring/TestBackend.ts b/packages/backend-test-utils/src/next/wiring/TestBackend.ts
index a273e879ce..7dbcf439dc 100644
--- a/packages/backend-test-utils/src/next/wiring/TestBackend.ts
+++ b/packages/backend-test-utils/src/next/wiring/TestBackend.ts
@@ -51,7 +51,6 @@ export interface TestBackendOptions<
     },
   ];
   features?: BackendFeature[];
-  autoStop?: 'afterEach' | 'never';
 }
 
 const defaultServiceFactories = [
@@ -60,7 +59,7 @@ const defaultServiceFactories = [
   lifecycleFactory(),
 ];
 
-const backendInstances = new Array<Backend>();
+const backendInstancesToCleanUp = new Array<Backend>();
 
 /** @alpha */
 export async function startTestBackend<
@@ -71,7 +70,6 @@ export async function startTestBackend<
     services = [],
     extensionPoints = [],
     features = [],
-    autoStop = 'afterEach',
     ...otherOptions
   } = options;
 
@@ -107,9 +105,7 @@ export async function startTestBackend<
     services: factories,
   });
 
-  if (autoStop) {
-    backendInstances.push(backend);
-  }
+  backendInstancesToCleanUp.push(backend);
 
   backend.add({
     id: `---test-extension-point-registrar`,
@@ -141,15 +137,15 @@ function registerTestHooks() {
   }
   registered = true;
 
-  afterEach(async () => {
-    for (const backend of backendInstances) {
+  afterAll(async () => {
+    for (const backend of backendInstancesToCleanUp) {
       try {
         await backend.stop();
       } catch (error) {
-        console.error(`Failed to stop backend after test, ${error}`);
+        console.error(`Failed to stop backend after tests, ${error}`);
       }
     }
-    backendInstances.length = 0;
+    backendInstancesToCleanUp.length = 0;
   });
 }