LLM-enhanced evolutionary test generation for untyped languages

Dynamic programming languages, such as Python, are widely used for their flexibility and support for rapid development. However, the absence of explicit parameter type declarations poses significant challenges in generating automated test cases. This often leads to random assignment of parameter types, increasing the search space and reducing testing efficiency. Current evolutionary algorithms, which rely heavily on random mutations, struggle to handle specific data types and frequently fall into local optima, making it difficult to generate high-quality test cases. Moreover, the resulting test suites often contain errors, preventing immediate usage in real-world applications. To address these challenges, this paper proposes the use of large language models to enhance test case generation for dynamic programming languages. Our method involves three key steps: analyzing parameter types to narrow the search space, introducing meaningful data during mutations to increase test case relevance, and using large language models to automatically repair errors in the generated test suites. Experimental results demonstrate a 16% improvement in test coverage, faster evolutionary cycles, and an increase in the number of executable test suites. These findings highlight the potential of large language models in improving both the efficiency and reliability of test case generation for dynamic programming languages.