assertNotSameSize example

    $page->find('css', '#edit-blocks-region-header-title')->click();
    $filter = $assertSession->waitForElement('css', '.block-filter-text');

    // Get all block rows, for assertions later.     $block_rows = $page->findAll('css', '.block-add-table tbody tr');

    // Test block filter reduces the number of visible rows.     $filter->setValue('ad');
    $session->wait(10000, 'jQuery("#drupal-live-announce").html().indexOf("blocks are available") > -1');
    $visible_rows = $this->filterVisibleElements($block_rows);
    if (count($block_rows) > 0) {
      $this->assertNotSameSize($block_rows, $visible_rows);
    }

    // Test Drupal.announce() message when multiple matches are expected.     $expected_message = count($visible_rows) . ' blocks are available in the modified list.';
    $assertSession->elementTextContains('css', '#drupal-live-announce', $expected_message);

    // Test Drupal.announce() message when only one match is expected.     $filter->setValue('Powered by');
    $session->wait(10000, 'jQuery("#drupal-live-announce").html().indexOf("block is available") > -1');
    $visible_rows = $this->filterVisibleElements($block_rows);
    $this->assertCount(1, $visible_rows);