fix upcasting iterator

prooph · Feb 11, 2017 · 6797c6d · 6797c6d
1 parent 778730a
commit 6797c6d
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Showing 2 changed files with 76 additions and 15 deletions.
diff --git a/src/Upcasting/UpcastingIterator.php b/src/Upcasting/UpcastingIterator.php
@@ -32,6 +32,8 @@ final class UpcastingIterator implements Iterator
      */
     private $storedMessages = [];
 
+    private $position = 0;
+
     public function __construct(Upcaster $upcaster, Iterator $iterator)
     {
         $this->upcaster = $upcaster;
@@ -44,29 +46,47 @@ public function current(): ?Message
             return reset($this->storedMessages);
         }
 
-        $messages = $this->upcaster->upcast($this->innerIterator->current());
+        $current = $this->innerIterator->current();
+
+        if (null === $current) {
+            return null;
+        }
 
-        if (empty($messages)) {
-            $this->next();
+        $this->storedMessages = $this->upcaster->upcast($current);
 
-            if ($this->valid()) {
-                return $this->current();
+        while (empty($this->storedMessages)) {
+            $this->innerIterator->next();
+
+            if (! $this->innerIterator->valid()) {
+                return null;
             }
-        }
 
-        $this->storedMessages = $messages;
+            $this->storedMessages = $this->upcaster->upcast($this->innerIterator->current());
+        }
 
-        return reset($messages);
+        return reset($this->storedMessages);
     }
 
     public function next(): void
     {
+        ++$this->position;
+
         if (! empty($this->storedMessages)) {
             array_shift($this->storedMessages);
         }
 
-        if (empty($this->storedMessages)) {
+        if (! empty($this->storedMessages)) {
+            return;
+        }
+
+        while (empty($this->storedMessages)) {
             $this->innerIterator->next();
+
+            if (! $this->innerIterator->valid()) {
+                return;
+            }
+
+            $this->storedMessages = $this->upcaster->upcast($this->innerIterator->current());
         }
     }
 
@@ -75,17 +95,18 @@ public function next(): void
      */
     public function key()
     {
-        return $this->innerIterator->key();
+        return $this->position;
     }
 
     public function valid(): bool
     {
-        return $this->innerIterator->valid();
+        return null !== $this->current();
     }
 
     public function rewind(): void
     {
         $this->storedMessages = [];
         $this->innerIterator->rewind();
+        $this->position = 0;
     }
 }
diff --git a/tests/Upcasting/UpcastingIteratorTest.php b/tests/Upcasting/UpcastingIteratorTest.php
@@ -31,13 +31,13 @@ public function it_iterates(): void
         $upcastedMessage2 = $upcastedMessage2->reveal();
 
         $message1 = $this->prophesize(Message::class);
-        $message1->metadata()->willReturn([])->shouldBeCalled();
-        $message1->withAddedMetadata('key', 'value')->willReturn($upcastedMessage1)->shouldBeCalled();
-        $message1->withAddedMetadata('key', 'another_value')->willReturn($upcastedMessage2)->shouldBeCalled();
+        $message1->metadata()->willReturn(['foo' => 'baz'])->shouldBeCalled();
         $message1 = $message1->reveal();
 
         $message2 = $this->prophesize(Message::class);
-        $message2->metadata()->willReturn(['foo' => 'baz'])->shouldBeCalled();
+        $message2->metadata()->willReturn([])->shouldBeCalled();
+        $message2->withAddedMetadata('key', 'value')->willReturn($upcastedMessage1)->shouldBeCalled();
+        $message2->withAddedMetadata('key', 'another_value')->willReturn($upcastedMessage2)->shouldBeCalled();
         $message2 = $message2->reveal();
 
         $message3 = $this->prophesize(Message::class);
@@ -46,10 +46,15 @@ public function it_iterates(): void
         $message3->withAddedMetadata('key', 'another_value')->shouldNotBeCalled();
         $message3 = $message3->reveal();
 
+        $message4 = $this->prophesize(Message::class);
+        $message4->metadata()->willReturn(['foo' => 'baz'])->shouldBeCalled();
+        $message4 = $message4->reveal();
+
         $iterator = new \ArrayIterator([
             $message1,
             $message2,
             $message3,
+            $message4,
         ]);
 
         $upcastingIterator = new UpcastingIterator($this->createUpcaster(), $iterator);
@@ -69,6 +74,41 @@ public function it_iterates(): void
         $this->assertSame($upcastedMessage2, $upcastingIterator->current());
         $upcastingIterator->next();
         $this->assertSame($message3, $upcastingIterator->current());
+        $upcastingIterator->next();
+        $this->assertFalse($upcastingIterator->valid());
+        $this->assertNull($upcastingIterator->current());
+    }
+
+    /**
+     * @test
+     */
+    public function it_iterates_on_iterator_with_removed_messages_only(): void
+    {
+        $message = $this->prophesize(Message::class);
+        $message->metadata()->willReturn(['foo' => 'baz'])->shouldBeCalled();
+        $message = $message->reveal();
+
+        $iterator = new \ArrayIterator([$message]);
+
+        $upcastingIterator = new UpcastingIterator($this->createUpcaster(), $iterator);
+
+        $this->assertEquals(0, $upcastingIterator->key());
+        $this->assertFalse($upcastingIterator->valid());
+        $this->assertNull($upcastingIterator->current());
+    }
+
+    /**
+     * @test
+     */
+    public function it_iterates_over_empty_iterator(): void
+    {
+        $iterator = new \ArrayIterator();
+
+        $upcastingIterator = new UpcastingIterator($this->createUpcaster(), $iterator);
+
+        $this->assertEquals(0, $upcastingIterator->key());
+        $this->assertFalse($upcastingIterator->valid());
+        $this->assertNull($upcastingIterator->current());
     }
 
     protected function createUpcaster(): SingleEventUpcaster