[5.4] Ensure Mailable view data is not overridden by order of operations

src/Illuminate/Mail/Mailable.php

@@ -520,7 +520,7 @@ public function subject($subject)
     public function markdown($view, array $data = [])
     {
         $this->markdown = $view;
-        $this->viewData = $data;
+        $this->viewData = array_merge($this->viewData, $data);
 
         return $this;
     }
@@ -535,7 +535,7 @@ public function markdown($view, array $data = [])
     public function view($view, array $data = [])
     {
         $this->view = $view;
-        $this->viewData = $data;
+        $this->viewData = array_merge($this->viewData, $data);
 
         return $this;
     }
@@ -550,7 +550,7 @@ public function view($view, array $data = [])
     public function text($textView, array $data = [])
     {
         $this->textView = $textView;
-        $this->viewData = $data;
+        $this->viewData = array_merge($this->viewData, $data);
 
         return $this;
     }

tests/Mail/MailMailableDataTest.php

@@ -0,0 +1,40 @@
+<?php
+
+namespace Illuminate\Tests\Mail;
+
+use Illuminate\Mail\Mailable;
+use PHPUnit\Framework\TestCase;
+
+class MailMailableDataTest extends TestCase
+{
+    public function testMailableDataIsNotLost()
+    {
+        $testData = ['first_name' => 'James'];
+
+        $mailable = new MailableStub;
+        $mailable->build(function($m) use ($testData) {
+            $m->view('view', $testData);
+        });
+        $this->assertSame($testData, $mailable->buildViewData());
+
+        $mailable = new MailableStub;
+        $mailable->build(function($m) use ($testData) {
+            $m->view('view', $testData)
+              ->text('text-view');
+        });
+        $this->assertSame($testData, $mailable->buildViewData());
+    }
+}
+
+class MailableStub extends Mailable
+{
+    /**
+     * Build the message.
+     *
+     * @return $this
+     */
+    public function build($builder)
+    {
+        $builder($this);
+    }
+}

tests/Mail/MailMailableTest.php

@@ -84,7 +84,7 @@ class WelcomeMailableStub extends Mailable
     public function build()
     {
         $this->with('first_name', 'Taylor')
-            ->withLastName('Otwell');
+             ->withLastName('Otwell');
     }
 }