README.md

metadata

license: apache-2.0
dataset_info:
  features:
    - name: repo
      dtype: string
    - name: base_commit
      dtype: string
    - name: num_java_files
      dtype: int32
    - name: num_loc
      dtype: int32
    - name: num_pom_xml
      dtype: int32
    - name: num_src_test_java_files
      dtype: int32
    - name: num_test_cases
      dtype: int32
    - name: license
      dtype: string
  splits:
    - name: test
      num_examples: 5102
programming_languages:
  - java
tags:
  - coding
  - code-migration
  - java
  - amazon
  - amazon-science
  - aws
task_categories:
  - text-generation

MigrationBench

1. 📖 Overview

🤗 MigrationBench is a large-scale code migration benchmark dataset at the repository level, across multiple programming languages.

• Current and initial release includes java 8 repositories with the maven build system, as of May 2025.

2. Datasets

There are three datasets in 🤗 MigrationBench:

• All repositories included in the datasets are available on GitHub, under the MIT or Apache-2.0 license.

Index	Dataset	Size	Notes
1	🤗 AmazonScience/migration-bench-java-full	5,102	Each repo has a test directory or at least one test case
2	🤗 AmazonScience/migration-bench-java-selected	300	A subset of 🤗 migration-bench-java-full
3	🤗 AmazonScience/migration-bench-java-utg	4,814	The unit test generation (utg) dataset, disjoint with 🤗 migration-bench-java-full

3. Metadata

Metadata is provided in the csv file for each dataset:

1. repo (str): The original repo URL without the https://github.com/ prefix
2. base_commit (str): Base commit id
   • At this commit with java 8 and maven, the repository is able to (1) compile and (2) pass existing unit tests and integration tests if any
   • It is the starting point for code migration from java 8
3. num_java_files (int): Number of *.java files in the repository at base_commit, similarly for all other num_* columns
4. num_loc (int): Lines of code for the repository
5. num_pom_xml (int): Number of modules (pom.xml files) in the repository
6. num_src_test_java_files (int): Number of *.java files in the dedicated src/test/ directory
7. num_test_cases (int): Number of test cases, based on running the mvn -f test . command in the root directory
   • Non negative values indicate number of test cases is parsed correctly from the output
   • Negative values means it's unable to parse the output: [INFO] Results: (-2) or [INFO] Tests run: (-1) regex is missing
8. license (str): The license of the repository, either MIT or Apache2.0 for the whole dataset

3.1 Parsing Java Test Cases

Here is a sample maven -f test . command output to get valid num_test_cases:

...
[INFO] Results:
[INFO]
[INFO] Tests run: 1, Failures: 0, Errors: 0, Skipped: 0
...

4. 📚 Citation

@misc{liu2025migrationbenchrepositorylevelcodemigration,
      title={MigrationBench: Repository-Level Code Migration Benchmark from Java 8},
      author={Linbo Liu and Xinle Liu and Qiang Zhou and Lin Chen and Yihan Liu and Hoan Nguyen and Behrooz Omidvar-Tehrani and Xi Shen and Jun Huan and Omer Tripp and Anoop Deoras},
      year={2025},
      eprint={2505.09569},
      archivePrefix={arXiv},
      primaryClass={cs.SE},
      url={https://arxiv.org/abs/2505.09569},
}