Merge pull request #2 from emonkak/fix-generator-exception-throwing

Avoid "Cannot rewind a generator that was already run" Exception

Author: emonkak

src/Iterator/LazyIterator.php

@@ -4,18 +4,41 @@
 
 use Emonkak\Collection\Utils\Iterators;
 
-class LazyIterator implements \IteratorAggregate
+class LazyIterator implements \Iterator
 {
     private $factory;
 
+    private $it;
+
     public function __construct(callable $factory)
     {
         $this->factory = $factory;
     }
 
-    public function getIterator()
+    public function current()
+    {
+        return $this->it->current();
+    }
+
+    public function key()
+    {
+        return $this->it->key();
+    }
+
+    public function next()
+    {
+        $this->it->next();
+    }
+
+    public function rewind()
     {
         $factory = $this->factory;
-        return Iterators::create($factory());
+        $this->it = Iterators::create($factory());
+        $this->it->rewind();
+    }
+
+    public function valid()
+    {
+        return $this->it->valid();
     }
 }

tests/AbstractCollectionTest.php

@@ -16,6 +16,11 @@ public function setUp()
         Collection::setDefaultProvider($this->getCollectionProvider());
     }
 
+    public function tearDown()
+    {
+        Collection::setDefaultProvider($this->defaultProvider);
+    }
+
     public function testFrom()
     {
         $it = new \EmptyIterator();
@@ -60,11 +65,6 @@ public function testCombineThrowsInvalidArgumentException()
         Collection::combine(1);
     }
 
-    public function tearDown()
-    {
-        Collection::setDefaultProvider($this->defaultProvider);
-    }
-
     public function testRange()
     {
         $result = Collection::range(0)->toList();
@@ -110,6 +110,16 @@ public function testRepeat()
         $this->assertEmpty($result);
     }
 
+    /**
+     * @dataProvider provideCollectionFactory
+     */
+    public function testGetIterator($factory)
+    {
+        $xs = $factory([1, 2, 3])->map(function($x) { return $x * 2; })->getIterator();
+        $this->assertSame([2, 4, 6], iterator_to_array($xs));
+        $this->assertSame([2, 4, 6], iterator_to_array($xs));
+    }
+
     /**
      * @dataProvider provideCollectionFactory
      */