added support for calling empty() and isset() on result document properties

library/Solarium/Plugin/MinimumScoreFilter/Document.php

@@ -104,6 +104,17 @@ class Document implements \IteratorAggregate, \Countable, \ArrayAccess
         return $this->document->__get($name);
     }
 
+    /**
+     * Forward isset call to the original document
+     *
+     * @param string $name
+     * @return boolean
+     */
+    public function __isset($name)
+    {
+        return $this->document->__isset($name);
+    }
+
     /**
      * IteratorAggregate implementation
      *

library/Solarium/QueryType/Select/Result/AbstractDocument.php

@@ -78,6 +78,20 @@ abstract class AbstractDocument implements \IteratorAggregate, \Countable, \Arra
         return $this->fields[$name];
     }
 
+    /**
+     * Check if field is set by name
+     *
+     * Magic method for checking if fields are set as properties of this document
+     * object, by field name. Also used by empty().
+     *
+     * @param  string $name
+     * @return boolean
+     */
+    public function __isset($name)
+    {
+        return isset($this->fields[$name]);
+    }
+
     /**
      * IteratorAggregate implementation
      *

tests/Solarium/Tests/QueryType/Select/Result/AbstractDocumentTest.php

@@ -60,6 +60,28 @@ abstract class AbstractDocumentTest extends \PHPUnit_Framework_TestCase
         );
     }
 
+    public function testPropertyIsset()
+    {
+        $this->assertTrue(
+            isset($this->doc->categories)
+        );
+
+        $this->assertFalse(
+            isset($this->doc->invalidfieldname)
+        );
+    }
+
+    public function testPropertyEmpty()
+    {
+        $this->assertTrue(
+            empty($this->doc->empty_field)
+        );
+
+        $this->assertFalse(
+            empty($this->doc->categories)
+        );
+    }
+
     public function testSetField()
     {
         $this->setExpectedException('Solarium\Exception\RuntimeException');