README.md

---
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
<table>
  <tr>
    <td style="padding: 0;">
      <a href="https://huggingface.co/collections/AmazonScience/migrationbench-68125452fc21a4564b92b6c3">
        <img src="https://img.shields.io/badge/-🤗 MigrationBench-4d5eff?style=flatten&labelColor" alt="MigrationBench (Hugging Face)">
      </a>
    </td>
    <td style="padding: 0;">
      <a href="https://github.com/amazon-science/MigrationBench">
        <img src="https://img.shields.io/badge/MigrationBench-000000?style=flatten&logo=github" alt="MigrationBench (GitHub)">
      </a>
    </td>
    <td style="padding: 0;">
      <a href="https://github.com/amazon-science/SDFeedback">
        <img src="https://img.shields.io/badge/SDFeedback-000000?style=flatten&logo=github&logoColor=white" alt="SDFeedback (GitHub)">
      </a>
    </td>
    <td style="padding: 0;">
      <a href="https://arxiv.org/abs/2505.09569">
        <img src="https://img.shields.io/badge/arXiv-2505.09569-b31b1b.svg?style=flatten" alt="MigrationBench (arXiv)">
      </a>
    </td>
    <td style="padding: 0; padding-left: 10px; vertical-align: middle;">
      <a href="https://huggingface.co/datasets/AmazonScience/migration-bench-java-full">
        <img src="https://img.shields.io/badge/-🤗 java--full-8a98ff?style=flat&labelColor" alt="java-full">
      </a>
    </td>
    <td style="padding: 0; vertical-align: middle;">
      <a href="https://huggingface.co/datasets/AmazonScience/migration-bench-java-selected">
        <img src="https://img.shields.io/badge/-🤗 java--selected-8a98ff?style=flat&labelColor" alt="java-selected">
      </a>
    </td>
    <td style="padding: 0; vertical-align: middle;">
      <a href="https://huggingface.co/datasets/AmazonScience/migration-bench-java-utg">
        <img src="https://img.shields.io/badge/-🤗 java--utg-8a98ff?style=flat&labelColor" alt="java-utg">
      </a>
    </td>
  </tr>
</table>


## 1. 📖 Overview

[🤗 MigrationBench](https://huggingface.co/collections/AmazonScience/migrationbench-68125452fc21a4564b92b6c3)
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](https://huggingface.co/collections/AmazonScience/migrationbench-68125452fc21a4564b92b6c3):
- 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`](https://huggingface.co/datasets/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`](https://huggingface.co/datasets/AmazonScience/migration-bench-java-selected) |   300 | A **subset** of [🤗 `migration-bench-java-full`](https://huggingface.co/datasets/AmazonScience/migration-bench-java-full)                                          |
| 3     | [🤗 `AmazonScience/migration-bench-java-utg`](https://huggingface.co/datasets/AmazonScience/migration-bench-java-utg)           | 4,814 | The unit test generation (utg) dataset, **disjoint** with [🤗 `migration-bench-java-full`](https://huggingface.co/datasets/AmazonScience/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
1. `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`
1. `num_java_files (int)`: Number of `*.java` files in the repository at `base_commit`, similarly for all other `num_*` columns
1. `num_loc (int)`: Lines of code for the repository
1. `num_pom_xml (int)`: Number of modules (`pom.xml` files) in the repository
1. `num_src_test_java_files (int)`: Number of `*.java` files in the dedicated `src/test/` directory
1. `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
1. `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

```bibtex
@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},
}
```