Omeka plugin should not be enabled without url

library/digital_resources/Omeka/Config.php

@@ -43,7 +43,7 @@ class Omeka_Config extends Class_DigitalResource_Config {
 
 
   public function isEnabled() {
-    return (new ZendAfi_Validate_Url())->isValid($this->getRootUrl());
+    return $this->getRootUrl() && ((new ZendAfi_Validate_Url())->isValid($this->getRootUrl()));
   }
 
 

library/digital_resources/Omeka/tests/OmekaTest.php

@@ -143,5 +143,12 @@ class OmekaHarvestedTest extends AbstractControllerTestCase {
     $this->assertXPathContentContains('//a[@class="omeka"][@href="http://omeka-demo.biblibre.com/items/show/659"]',
                                       'ressource sur Omeka');
   }
+
+
+  /** @test */
+  public function withoutRootURLShouldBeDisabled() {
+    Class_AdminVar::set('Omeka_ROOT_URL', '');
+    $this->assertFalse((new Class_DigitalResource())->configFor('Omeka')->isEnabled());
+  }
 }
 ?>
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