Merge pull request #35 from chadicus/fea/array-column

Add Collection::column()

Author: chadicus

src/Collection.php

@@ -186,4 +186,18 @@ public function current()
 
         return $this->_result[$this->_position];
     }
+
+    /**
+     * Returns the values from a single field this collection, identified by the given $key.
+     *
+     * @param string $key The name of the field for which the values will be returned.
+     *
+     * @return iterable
+     */
+    public function column($key)
+    {
+        foreach ($this as $item) {
+            yield Util\Arrays::get($item, $key);
+        }
+    }
 }

tests/CollectionTest.php

@@ -242,6 +242,23 @@ public function oneItemCollection()
             $this->assertSame(['id' => '0', 'key' => 0], $item);
         }
     }
+
+    /**
+     * Verifies basic behavior of column().
+     *
+     * @test
+     * @covers ::column
+     */
+    public function column()
+    {
+        $authentication = Authentication::createClientCredentials('not under test', 'not under test');
+        $client = new Client(new CollectionAdapter(), $authentication, 'not under test');
+        $collection = new Collection($client, 'basic', ['limit' => 3]);
+        $this->assertSame(
+            [0, 1, 2, 3, 4],
+            iterator_to_array($collection->column('key'))
+        );
+    }
 }
 
 final class CollectionAdapter implements Adapter