Add repository merge base API support

Author: drumm

lib/Gitlab/Api/Repositories.php

@@ -460,4 +460,14 @@ public function archive($project_id, $params = array(), $format = 'tar.gz')
     {
         return $this->get($this->getProjectPath($project_id, 'repository/archive.'.$format), $params);
     }
+
+    /**
+     * @param int $project_id
+     * @param array $refs
+     * @return mixed
+     */
+    public function mergeBase($project_id, $refs)
+    {
+        return $this->get($this->getProjectPath($project_id, 'repository/merge_base'), array('refs' => $refs));
+    }
 }

test/Gitlab/Tests/Api/ProjectsTest.php

@@ -193,6 +193,38 @@ public function shouldArchiveProject()
         $this->assertEquals($expectedArray, $api->archive(1));
     }
 
+    /**
+     * @test
+     */
+    public function shouldGetMergeBase()
+    {
+        $expectedArray = array(
+            'id' => 'abcd1234abcd1234abcd1234abcd1234abcd1234',
+            'short_id' => 'abcd1234',
+            'title' => 'A commit',
+            'created_at' => '2018-01-01T00:00:00.000Z',
+            'parent_ids' => array(
+               'efgh5678efgh5678efgh5678efgh5678efgh5678',
+            ),
+            'message' => 'A commit',
+            'author_name' => 'Jane Doe',
+            'author_email' => '[email protected]',
+            'authored_date' => '2018-01-01T00:00:00.000Z',
+            'committer_name' => 'Jane Doe',
+            'committer_email' => '[email protected]',
+            'committed_date' => '2018-01-01T00:00:00.000Z',
+        );
+
+        $api = $this->getApiMock();
+        $api->expects($this->once())
+            ->method('get')
+            ->with('projects/1/repository/merge_base', array('refs' => array('efgh5678efgh5678efgh5678efgh5678efgh5678', '1234567812345678123456781234567812345678')))
+            ->will($this->returnValue($expectedArray))
+        ;
+
+        $this->assertEquals($expectedArray, $api->archive(1, array('efgh5678efgh5678efgh5678efgh5678efgh5678', '1234567812345678123456781234567812345678')));
+    }
+
     /**
      * @test
      */