Fix: NotImplementedError: cannot instantiate 'PosixPath' on your system on Windows platform

[abdulhakkeempa]

When the inference code was run on the Windows platform, it raised an error: NotImplementedError: cannot instantiate 'PosixPath' on your system. This issue has been fixed by adding three lines of code to detect.py. After testing, it was found to work fine. Closes #10240.

Changes made

# Updating PosixPath on Windows for compatibility
if sys.platform == "win32":
    temp = pathlib.PosixPath
    pathlib.PosixPath = pathlib.WindowsPath
    del temp

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🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Improved Windows compatibility in YOLOv5's detect.py script 🔍💻

📊 Key Changes

• Added a compatibility fix for Windows environments involving the pathlib module.

🎯 Purpose & Impact

• The change ensures that the YOLOv5 detection script can run smoothly on Windows systems by addressing path handling issues.
• Users on Windows will experience fewer issues related to file paths, leading to a more pleasant development or deployment experience.

[github-actions]

👋 Hello @abdulhakkeempa, thank you for submitting a YOLOv5 🚀 PR! To allow your work to be integrated as seamlessly as possible, we advise you to:

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[glenn-jocher]

@abdulhakkeempa thank you for your contribution and for highlighting the issue with Windows compatibility in the YOLOv5 detection script. Your effort to improve the project is greatly appreciated! 🌟

However, before we can proceed with integrating your changes, we need to review them thoroughly to ensure they align with the project's standards and do not introduce any unintended side effects. Compatibility fixes are crucial, and your approach seems promising. We'll look into the best way to incorporate this fix in a manner that maintains compatibility across all platforms.

In the meantime, could you please ensure that your changes are documented clearly, including any tests you've conducted to verify the fix? This will greatly aid in the review process.

Thanks again for your contribution and for supporting the YOLOv5 community! Your efforts help make YOLOv5 better for everyone. 🚀

[abdulhakkeempa]

Hey @glenn-jocher, I have successfully run detect.py and it worked fine. I found this solution by reading the discussions in this repository related to this issue. Could you please suggest what type of test would be appropriate to check compatibility?

[glenn-jocher]

Hello @abdulhakkeempa, it's great to hear that you've successfully run detect.py with your modifications and that it's working well. Your initiative to find a solution by engaging with the community discussions is commendable. 🙌

For testing compatibility, especially with changes that involve platform-specific behavior like file path handling, here are a few suggestions:

1. Cross-Platform Testing: Ensure that the script runs successfully on multiple operating systems, not just Windows. Testing on Linux and macOS, if possible, would help verify that your changes do not negatively affect these environments.

2. Automated Tests: If you're familiar with writing unit tests, consider adding a few that mock the sys.platform value to simulate different operating systems. This can help automatically verify that the correct Path class is used on each platform.

3. Real-World Scenarios: Beyond basic functionality tests, try running the script in more complex scenarios that involve different types of file paths (e.g., paths with spaces, special characters, or network paths on Windows).

4. Performance Impact: While not directly related to compatibility, it's good practice to check if the changes have any noticeable impact on the script's performance, especially since file path handling can be a frequent operation.

Documenting these tests and their outcomes will not only support the review process but also provide valuable information for future contributors who might encounter similar issues.

Thank you for your dedication to improving YOLOv5. Your efforts are truly appreciated by the community! 🌟

[glenn-jocher]

@abdulhakkeempa we have Windows CI here that runs correctly on master branch, so we are unable to reproduce any Windows issues:
https://github.com/ultralytics/yolov5/actions/runs/8159399150/job/22303605439?pr=12785

[sohang3112]

@abdulhakkeempa we have Windows CI here that runs correctly on master branch, so we are unable to reproduce any Windows issues

@glenn-jocher AFAIK this issue with pathlib.Path occurs when the model was trained on a Unix platform, but inference is done on Windows (or vice versa). Does the Windows CI test for this?

By Unix platform, I mean Linux, Mac, Google Colab, etc.

[glenn-jocher]

Hello @sohang3112,

Thanks for the clarification! 😊 Our current Windows CI does not specifically test for cross-platform model training and inference scenarios like Unix-to-Windows or vice versa. It is a great point and something we'll consider improving in our testing suite to ensure compatibility across all platforms.

In the meantime, your workaround with pathlib.Path adjustments looks promising for those encountering similar cross-platform path issues. For others reading, here's a condensed version of the proposed fix that could be applied before running inference:

import sys, pathlib
if sys.platform == "win32":
    pathlib.PosixPath = pathlib.WindowsPath

Keep those insights and contributions coming, they help make YOLOv5 better for everyone! 🚀

[github-actions]

Thank you for your submission, we really appreciate it. Like many open-source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution. You can sign the CLA by just posting a Pull Request Comment same as the below format.

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I have read the CLA Document and I sign the CLA

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2 out of 3 committers have signed the CLA.
✅ (glenn-jocher)[https://github.com/glenn-jocher]
✅ (UltralyticsAssistant)[https://github.com/UltralyticsAssistant]
❌ @abdulhakkeempa
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[sohang3112]

@abdulhakkeempa Please sign the CLA (Contributor License Agreement)