Add count() and improve one() to ResultSet

one() should work even if the ResultSet has been serialized. Adding
support for count() as other parts of the framework expect that result
sets are countable.

Cake/ORM/ResultSet.php

@@ -18,6 +18,7 @@
 
 use Cake\Database\Exception;
 use Cake\Database\Type;
+use \Countable;
 use \Iterator;
 use \JsonSerializable;
 use \Serializable;
@@ -29,7 +30,7 @@
  * queries required for eager loading external associations.
  *
  */
-class ResultSet implements Iterator, Serializable, JsonSerializable {
+class ResultSet implements Countable, Iterator, Serializable, JsonSerializable {
 
 	use ResultCollectionTrait;
 
@@ -43,7 +44,7 @@ class ResultSet implements Iterator, Serializable, JsonSerializable {
 /**
  * Database statement holding the results
  *
- * @var \Cake\Database\Statement
+ * @var \Cake\Database\StatementInterface
  */
 	protected $_statement;
 
@@ -115,7 +116,7 @@ class ResultSet implements Iterator, Serializable, JsonSerializable {
  * Constructor
  *
  * @param Query from where results come
- * @param \Cake\Database\Statement $statement
+ * @param \Cake\Database\StatementInterface $statement
  * @return void
  */
 	public function __construct($query, $statement) {
@@ -192,7 +193,11 @@ public function valid() {
 
 /**
  * Returns the first result in this set and blocks the set so that no other
- * results can be fetched
+ * results can be fetched.
+ *
+ * When using serialized results, the index will be incremented past the
+ * end of the results simulating the behavior when the result set is backed
+ * by a statement.
  *
  * @return array|object
  */
@@ -201,11 +206,28 @@ public function one() {
 			if ($this->_statement) {
 				$this->_statement->closeCursor();
 			}
+			if (!$this->_statement && $this->_results) {
+				$this->_index = count($this->_results);
+			}
 			return $this->_current;
 		}
 		return null;
 	}
 
+/**
+ * Gives the number of rows in the result set.
+ *
+ * Part of the countable interface.
+ *
+ * @return integer
+ */
+	public function count() {
+		if ($this->_statement) {
+			return $this->_statement->rowCount();
+		}
+		return count($this->_results);
+	}
+
 /**
  * Calculates the list of associations that should get eager loaded
  * when fetching each record

Cake/Test/TestCase/ORM/ResultSetTest.php

@@ -30,6 +30,11 @@ class ResultSetTest extends TestCase {
 
 	public $fixtures = ['core.article'];
 
+/**
+ * setup
+ *
+ * @return void
+ */
 	public function setUp() {
 		parent::setUp();
 		$this->connection = ConnectionManager::get('test');
@@ -128,4 +133,62 @@ public function testJsonSerialize() {
 		$this->assertEquals($expected, json_encode($results));
 	}
 
+/**
+ * Test one() method with a statement backed result set.
+ *
+ * @return void
+ */
+	public function testOne() {
+		$query = $this->table->find('all');
+		$results = $query->hydrate(false)->execute();
+
+		$row = $results->one();
+		$this->assertEquals($this->fixtureData[0], $row);
+
+		$this->assertNull($results->one(), 'No more rows.');
+		$this->assertNull($results->one(), 'No more rows.');
+	}
+
+/**
+ * Test one() method with a result set that has been unserialized
+ *
+ * @return void
+ */
+	public function testOneAfterSerialize() {
+		$query = $this->table->find('all');
+		$results = $query->hydrate(false)->execute();
+		$results = unserialize(serialize($results));
+
+		$row = $results->one();
+		$this->assertEquals($this->fixtureData[0], $row);
+
+		$this->assertNull($results->one(), 'No more rows.');
+		$this->assertNull($results->one(), 'No more rows.');
+	}
+
+/**
+ * Test the countable interface.
+ *
+ * @return void
+ */
+	public function testCount() {
+		$query = $this->table->find('all');
+		$results = $query->execute();
+
+		$this->assertCount(3, $results, 'Should be countable and 3');
+	}
+
+/**
+ * Test the countable interface after unserialize
+ *
+ * @return void
+ */
+	public function testCountAfterSerialize() {
+		$query = $this->table->find('all');
+		$results = $query->execute();
+		$results = unserialize(serialize($results));
+
+		$this->assertCount(3, $results, 'Should be countable and 3');
+	}
+
 }