feat: add support for Symbol.dispose (#120)

Author: Julien-R44

src/fake_mailer.ts

@@ -527,9 +527,16 @@ class MessagesCollection {
 export class FakeMailer extends Mailer<JSONTransport> implements MailerContract<JSONTransport> {
   mails = new MailsCollection()
   messages = new MessagesCollection()
+  #onDispose?: () => void
 
-  constructor(name: string, emitter: EmitterLike<MailEvents>, config: MailerConfig) {
+  constructor(
+    name: string,
+    emitter: EmitterLike<MailEvents>,
+    config: MailerConfig,
+    onDispose?: () => void
+  ) {
     super(name, new JSONTransport(), emitter, config)
+    this.#onDispose = onDispose
     super.setMessenger({
       queue: async (mail, sendConfig) => {
         return this.sendCompiled(mail, sendConfig)
@@ -585,6 +592,10 @@ export class FakeMailer extends Mailer<JSONTransport> implements MailerContract<
     }, config)
   }
 
+  [Symbol.dispose]() {
+    this.#onDispose?.()
+  }
+
   async close() {
     this.messages.clear()
     this.mails.clear()

src/mail_manager.ts

@@ -148,7 +148,7 @@ export class MailManager<KnownMailers extends Record<string, MailManagerTranspor
     this.restore()
 
     debug('creating fake mailer')
-    this.#fakeMailer = new FakeMailer('fake', this.#emitter, this.config)
+    this.#fakeMailer = new FakeMailer('fake', this.#emitter, this.config, () => this.restore())
     return this.#fakeMailer
   }
 

tests/integration/mail_manager.spec.ts

@@ -296,6 +296,36 @@ test.group('Mail manager', () => {
     assert.lengthOf(messages.sent(), 0)
   })
 
+  test('restore fake mailer using Symbol.dispose', async ({ assert }) => {
+    const emitter = new Emitter<MailEvents>(app)
+
+    const mail = new MailManager(emitter, {
+      mailers: {
+        mailer1: () => new JSONTransport(),
+      },
+    })
+
+    let messages: ReturnType<typeof mail.fake>['messages']
+
+    {
+      using fake = mail.fake()
+      await mail.use('mailer1').send((message) => {
+        message.to('foo@bar.com')
+        message.subject('Verify email address')
+      })
+
+      fake.messages.assertSent({ subject: 'Verify email address' })
+      assert.lengthOf(fake.messages.sent(), 1)
+      messages = fake.messages
+    }
+
+    /**
+     * After the block, the fake mailer should be disposed
+     * and messages should be cleared
+     */
+    assert.lengthOf(messages!.sent(), 0)
+  })
+
   test('close all mailers and remove from cache', async ({ assert }) => {
     const emitter = new Emitter<MailEvents>(app)
     const smtpTransport = new SMTPTransport({