fix: calling terminate multiple times (#37)

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@adonisjs/application",
-  "version": "8.4.1",
+  "version": "8.4.2",
   "description": "AdonisJS application class to read app related data",
   "type": "module",
   "main": "build/index.js",

src/application.ts

@@ -624,6 +624,11 @@ export class Application<ContainerBindings extends Record<any, any>> extends Mac
       return
     }
 
+    if (this.#terminating) {
+      debug('app is already being terminated')
+      return
+    }
+
     const shutdownInReverseOrder = this.experimentalFlags.enabled('shutdownInReverseOrder')
 
     debug('terminating app')

tests/application/terminate.spec.ts

@@ -0,0 +1,35 @@
+/*
+ * @adonisjs/application
+ *
+ * (c) AdonisJS
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+import { test } from '@japa/runner'
+import { Application } from '../../src/application.js'
+
+const BASE_URL = new URL('./app/', import.meta.url)
+
+test.group('Application | terminate', () => {
+  test('do not terminate app multiple times', async ({ assert }) => {
+    const stack: string[] = []
+
+    const app = new Application(BASE_URL, {
+      environment: 'web',
+    })
+
+    await app.init()
+    await app.boot()
+
+    app.terminating(() => {
+      stack.push('terminating')
+    })
+
+    await Promise.all([app.terminate(), app.terminate()])
+
+    assert.deepEqual(stack, ['terminating'])
+    assert.equal(app.getState(), 'terminated')
+  })
+})