diff --git modules/file/tests/file.test modules/file/tests/file.test
index 7e1457e..3ab0f52 100644
--- modules/file/tests/file.test
+++ modules/file/tests/file.test
@@ -114,8 +114,8 @@ class FileFieldTestCase extends DrupalWebTestCase {
     );
 
     if (is_numeric($nid_or_type)) {
-      $node = node_load($nid_or_type);
-      $delta = isset($node->$field_name) ? count($node->$field_name) : 0;
+      $node = node_load($nid_or_type, NULL, TRUE);
+      $delta = isset($node->{$field_name}[LANGUAGE_NONE]) ? count($node->{$field_name}[LANGUAGE_NONE]) : 0;
       $edit['files[' . $field_name . '_' . LANGUAGE_NONE . '_' . $delta . ']'] = drupal_realpath($file->uri);
       $this->drupalPost('node/' . $nid_or_type . '/edit', $edit, t('Save'));
     }
@@ -280,6 +280,17 @@ class FileFieldWidgetTestCase extends FileFieldTestCase {
       $this->assertTrue(empty($node->{$field_name}[LANGUAGE_NONE][0]['fid']), t('File was successfully removed from the node.'));
     }
 
+    // Test partial form submissions using the Upload button on a multivalue field.
+    field_delete_field($field_name);
+    $this->createFileField($field_name, $type_name, array('cardinality' => 3));
+
+    $this->drupalGet("node/add/$type_name");
+    for ($delta = 0; $delta < 3; $delta++) {
+      $edit = array('files[' . $field_name . '_' . LANGUAGE_NONE . '_' . $delta . ']' => drupal_realpath($test_file->uri));
+      $this->drupalPost(NULL, $edit, t('Upload'));
+    }
+    $this->assertNoFieldByXpath('//input[@type="submit"]', t('Upload'), t('After uploading 3 files, the "Upload" button is no longer displayed.'));
+
     // Test private download method.
     $edit = array('field[settings][uri_scheme]' => 'private');
     $this->drupalPost("admin/structure/types/manage/$type_name/fields/$field_name", $edit, t('Save settings'));