Add method to swap registered generators (#238)

Author: dmason30

src/Blueprint.php

@@ -91,4 +91,15 @@ public function registerGenerator(Generator $generator)
     {
         $this->generators[] = $generator;
     }
+
+    public function swapGenerator(string $concrete, Generator $generator)
+    {
+        foreach ($this->generators as $key => $registeredGenerator) {
+            if (get_class($registeredGenerator) === $concrete) {
+                unset($this->generators[$key]);
+            }
+        }
+
+        $this->registerGenerator($generator);
+    }
 }

tests/Feature/BlueprintTest.php

@@ -355,6 +355,34 @@ public function generate_uses_registered_generators_and_returns_generated_files(
         ], $this->subject->generate($tree));
     }
 
+    /**
+     * @test
+     */
+    public function generate_uses_swapped_generator_and_returns_generated_files()
+    {
+        $generatorOne = \Mockery::mock(Generator::class);
+        $tree = ['branch' => ['code', 'attributes']];
+        $generatorOne->expects('output')->never();
+
+        $generatorSwap = \Mockery::mock(Generator::class);
+        $generatorSwap->expects('output')
+            ->with($tree)
+            ->andReturn([
+                'created' => ['swapped/new.php'],
+                'updated' => ['swapped/existing.php'],
+                'deleted' => ['swapped/trashed.php']
+            ]);
+
+        $this->subject->registerGenerator($generatorOne);
+        $this->subject->swapGenerator(get_class($generatorOne), $generatorSwap);
+
+        $this->assertEquals([
+            'created' => ['swapped/new.php'],
+            'updated' => ['swapped/existing.php'],
+            'deleted' => ['swapped/trashed.php'],
+        ], $this->subject->generate($tree));
+    }
+
     /**
      * @test
      * @dataProvider namespacesDataProvider