support bus chain on fake

src/Illuminate/Support/Testing/Fakes/BusFake.php

@@ -360,6 +360,19 @@ public function dispatchAfterResponse($command)
         }
     }
 
+    /**
+     * Create a new chain of queueable jobs.
+     *
+     * @param  \Illuminate\Support\Collection|array  $jobs
+     * @return \Illuminate\Foundation\Bus\PendingChain
+     */
+    public function chain($jobs)
+    {
+        $jobs = Collection::wrap($jobs);
+
+        return new PendingChainFake($this, $jobs->shift(), $jobs->toArray());
+    }
+
     /**
      * Attempt to find the batch with the given ID.
      *

src/Illuminate/Support/Testing/Fakes/PendingChainFake.php

@@ -0,0 +1,56 @@
+<?php
+
+namespace Illuminate\Support\Testing\Fakes;
+
+use Closure;
+use Illuminate\Foundation\Bus\PendingChain;
+use Illuminate\Queue\CallQueuedClosure;
+
+class PendingChainFake extends PendingChain
+{
+    /**
+     * The fake bus instance.
+     *
+     * @var \Illuminate\Support\Testing\Fakes\BusFake
+     */
+    protected $bus;
+
+    /**
+     * Create a new pending chain instance.
+     *
+     * @param  \Illuminate\Support\Testing\Fakes\BusFake  $bus
+     * @param  mixed  $job
+     * @param  array  $chain
+     * @return void
+     */
+    public function __construct(BusFake $bus, $job, $chain)
+    {
+        $this->bus = $bus;
+        $this->job = $job;
+        $this->chain = $chain;
+    }
+
+    /**
+     * Dispatch the job with the given arguments.
+     *
+     * @return \Illuminate\Foundation\Bus\PendingDispatch
+     */
+    public function dispatch()
+    {
+        if (is_string($this->job)) {
+            $firstJob = new $this->job(...func_get_args());
+        } elseif ($this->job instanceof Closure) {
+            $firstJob = CallQueuedClosure::create($this->job);
+        } else {
+            $firstJob = $this->job;
+        }
+
+        $firstJob->allOnConnection($this->connection);
+        $firstJob->allOnQueue($this->queue);
+        $firstJob->chain($this->chain);
+        $firstJob->delay($this->delay);
+        $firstJob->chainCatchCallbacks = $this->catchCallbacks();
+
+        return $this->bus->dispatch($firstJob);
+    }
+}