remove null transport

Signed-off-by: Abdul Malik Ikhsan <samsonasik@gmail.com>

Author: samsonasik

src/Transport/Factory.php

@@ -20,7 +20,6 @@ abstract class Factory
         'file'      => File::class,
         'inmemory'  => InMemory::class,
         'memory'    => InMemory::class,
-        'null'      => InMemory::class,
         'sendmail'  => Sendmail::class,
         'smtp'      => Smtp::class,
     ];

src/Transport/Null.php

@@ -77,10 +77,6 @@ public function typeProvider()
             [Smtp::class],
         ];
 
-        if (version_compare(PHP_VERSION, '7.0', '<')) {
-            $types[] = [NullTransport::class];
-        }
-
         return $types;
     }
 
@@ -102,15 +98,12 @@ public function typeAliasProvider()
     {
         return [
             ['file', File::class],
-            ['null', InMemory::class],
             ['memory', InMemory::class],
             ['inmemory', InMemory::class],
             ['InMemory', InMemory::class],
             ['sendmail', Sendmail::class],
             ['smtp', Smtp::class],
             ['File', File::class],
-            ['Null', InMemory::class],
-            ['NULL', InMemory::class],
             ['Sendmail', Sendmail::class],
             ['SendMail', Sendmail::class],
             ['Smtp', Smtp::class],
@@ -124,7 +117,7 @@ public function typeAliasProvider()
     public function testCanUseTraversableAsSpec()
     {
         $spec = new ArrayObject([
-            'type' => 'null'
+            'type' => 'inMemory'
         ]);
 
         $transport = Factory::create($spec);