BlockForm example

->method('condition')
      ->willReturn($query);

    $query->expects($this->exactly(5))
      ->method('execute')
      ->willReturn(['test', 'other_test', 'other_test_1', 'other_test_2']);

    $this->storage->expects($this->exactly(5))
      ->method('getQuery')
      ->willReturn($query);

    $block_form_controller = new BlockForm($this->entityTypeManager, $this->conditionManager, $this->contextRepository, $this->language, $this->themeHandler, $this->pluginFormFactory->reveal());

    // Ensure that the block with just one other instance gets the next available     // name suggestion.     $this->assertEquals('test_2', $block_form_controller->getUniqueMachineName($blocks['test']));

    // Ensure that the block with already three instances (_0, _1, _2) gets the     // 4th available name.     $this->assertEquals('other_test_3', $block_form_controller->getUniqueMachineName($blocks['other_test']));
    $this->assertEquals('other_test_3', $block_form_controller->getUniqueMachineName($blocks['other_test_1']));
    $this->assertEquals('other_test_3', $block_form_controller->getUniqueMachineName($blocks['other_test_2']));