fix: let it work with --runInBand

Hack into the AdonisJS application to allow it to be restarted after
being shut down.

adonis-environment.js

@@ -7,11 +7,14 @@ const NodeEnvironment = require('jest-environment-node');
 
 const iocSymbol = Symbol.for('ioc.use');
 
+let app;
+let providersWithReadyHook;
+let providersWithShutdownHook;
+
 class AdonisEnvironment extends NodeEnvironment {
   constructor(config, context) {
     super(config, context);
     this.rootDir = config.rootDir;
-    this.app = null;
 
     const options = {
       cache: true,
@@ -25,21 +28,30 @@ class AdonisEnvironment extends NodeEnvironment {
     register(this.rootDir, options);
   }
 
+  async createApplication() {
+    if (!app) {
+      const ignitor = new Ignitor(this.rootDir);
+      app = ignitor.application('test');
+      await app.setup();
+      await app.registerProviders();
+      await app.bootProviders();
+      await app.requirePreloads();
+      providersWithReadyHook = app.providersWithReadyHook;
+      providersWithShutdownHook = app.providersWithShutdownHook;
+    }
+  }
+
   async setup() {
     await super.setup();
-    const ignitor = new Ignitor(this.rootDir);
     // Set by Jest
     if (process.env.NODE_ENV === 'test') {
       process.env.NODE_ENV = 'testing';
     }
     try {
-      const app = ignitor.application('test');
-      await app.setup();
-      await app.registerProviders();
-      await app.bootProviders();
-      await app.requirePreloads();
+      await this.createApplication();
+      app.providersWithReadyHook = providersWithReadyHook;
+      app.providersWithShutdownHook = providersWithShutdownHook;
       await app.start();
-      this.app = app;
       this.global[iocSymbol] = global[iocSymbol];
     } catch (e) {
       console.error('Error while setting up Adonis test environment');
@@ -49,7 +61,9 @@ class AdonisEnvironment extends NodeEnvironment {
   }
 
   async teardown() {
-    await this.app.shutdown();
+    await app.shutdown();
+    app.isShuttingDown = false;
+    app.state = 'booted';
     await super.teardown();
   }
 }