Merge pull request #2570 from malarzm/counting-caching-iterator

Preserve iterator position when counting

Author: malarzm

lib/Doctrine/ODM/MongoDB/Iterator/CachingIterator.php

@@ -58,7 +58,9 @@ public function __construct(Traversable $iterator)
     /** @see https://php.net/countable.count */
     public function count(): int
     {
+        $currentKey = key($this->items);
         $this->exhaustIterator();
+        for (reset($this->items); key($this->items) !== $currentKey; next($this->items));
 
         return count($this->items);
     }

tests/Doctrine/ODM/MongoDB/Tests/Functional/Iterator/CachingIteratorTest.php

@@ -114,26 +114,32 @@ public function testToArrayAfterPartialIteration(): void
     public function testCount(): void
     {
         $iterator = new CachingIterator($this->getTraversable([1, 2, 3]));
-        $this->assertCount(3, $iterator);
+        self::assertCount(3, $iterator);
     }
 
     public function testCountAfterPartialIteration(): void
     {
         $iterator = new CachingIterator($this->getTraversable([1, 2, 3]));
 
         $iterator->rewind();
-        $this->assertTrue($iterator->valid());
-        $this->assertSame(0, $iterator->key());
-        $this->assertSame(1, $iterator->current());
+        self::assertTrue($iterator->valid());
+        self::assertSame(0, $iterator->key());
+        self::assertSame(1, $iterator->current());
 
         $iterator->next();
-        $this->assertCount(3, $iterator);
+        self::assertSame(1, $iterator->key());
+        self::assertSame(2, $iterator->current());
+
+        self::assertCount(3, $iterator);
+        self::assertTrue($iterator->valid());
+        self::assertSame(1, $iterator->key());
+        self::assertSame(2, $iterator->current());
     }
 
     public function testCountWithEmptySet(): void
     {
         $iterator = new CachingIterator($this->getTraversable([]));
-        $this->assertCount(0, $iterator);
+        self::assertCount(0, $iterator);
     }
 
     /**
@@ -172,7 +178,7 @@ public function rewind(): void
         };
 
         $iterator = new CachingIterator($nestedIterator);
-        $this->assertCount(1, $iterator);
+        self::assertCount(1, $iterator);
     }
 
     /**