Make handle method optional

See #39

src/Action.php

@@ -137,6 +137,10 @@ protected function handleRun(array $attributes = [])
         $this->resolveAuthorization();
         $this->resolveValidation();
 
+        if (! method_exists($this, 'handle')) {
+            return;
+        }
+
         return $this->resolveAndCall($this, 'handle');
     }
 

tests/RunsAsObjectsTest.php

@@ -3,6 +3,7 @@
 namespace Lorisleiva\Actions\Tests;
 
 use BadMethodCallException;
+use Lorisleiva\Actions\Action;
 use Lorisleiva\Actions\Tests\Actions\SimpleCalculator;
 
 class RunsAsObjectsTest extends TestCase
@@ -195,16 +196,26 @@ public function it_returns_a_subset_of_the_attributes_of_an_action()
         ]);
 
         $this->assertEquals(
-            ['operation' => 'addition'], 
+            ['operation' => 'addition'],
             $action->only('operation')
         );
 
         $this->assertEquals(
-            ['right' => 5], 
+            ['right' => 5],
             $action->except('operation', 'left')
         );
     }
 
+    /** @test */
+    public function actions_can_have_no_handle_method()
+    {
+        // An empty action...
+        $action = new class() extends Action {};
+
+        // ...returns null without throwing any exceptions.
+        $this->assertNull($action->run());
+    }
+
     /** @test */
     public function it_can_override_the_way_we_get_attribute_from_the_constructor()
     {
@@ -240,7 +251,7 @@ public function it_can_override_constructor_attributes_by_reflecting_the_propert
         $action = new class('addition', 3, 5) extends SimpleCalculator {
             protected $getAttributesFromConstructor = true;
 
-            public function handle($operation, $left, $right) 
+            public function handle($operation, $left, $right)
             {
                 return parent::handle($operation, $left, $right);
             }
@@ -281,4 +292,4 @@ public function it_throws_an_exception_when_calling_missing_methods()
             $this->assertEquals('Method Lorisleiva\Actions\Tests\Actions\SimpleCalculator::missingStaticMethod does not exist.', $e->getMessage());
         }
     }
-}
+}