Context: Most modern programming environments support refactorings. Although refactorings are relevant to improve the quality of software source code, they unfortunately suffer from severe usability issues. In particular, the extract method refactoring, one of the most prominent refactorings, has a failure rate of 49% when users attempt to use it.

Objective: Our main objective is to improve the success rate of applying the extract method refactoring.

Methods: First, to understand the cause of refactoring failure, we conducted a partial replication of Vakilian's ICSE '14 study about usability issues of refactoring using IntelliJ IDEA. Second, we designed and implemented TOAD, a tool that proposes alternative text selection for source code refactoring for the Pharo programming language. Third, we evaluated TOAD using a controlled experiment against the standard Pharo code refactoring tool. Seven professional software engineers complemented with three undergrad students participated in our experiments.

Conclusion: The causes we identified of failed extract method refactoring attempts match Vakilian's work. TOAD significantly reduces the number of failed attempts to run the extract method refactoring at a lower cognitive load cost.

上下文：大多数现代编程环境都支持重构。尽管重构与提高软件源代码的质量有关，但不幸的是，它们存在严重的可用性问题。特别是，提取方法重构是最重要的重构之一，当用户尝试使用它时，其失败率高达49％。

目的：我们的主要目标是提高应用提取方法重构的成功率。

方法：首先，为了了解重构失败的原因，我们对Vakilian的ICSE '14研究进行了部分复制，该研究涉及使用IntelliJ IDEA进行重构的可用性问题。其次，我们设计并实现了TOAD，该工具可为Pharo编程语言的源代码重构提出替代性的文本选择方法。第三，我们使用对照标准Pharo代码重构工具的对照实验评估了TOAD。七名专业软件工程师和三名本科生参加了我们的实验。

结论：我们确定提取方法重构尝试失败的原因与Vakilian的工作相符。TOAD显着减少了以较低的认知负载成本运行提取方法重构的失败尝试次数。