fix ckpt dir check

[justadogistaken]

Motivation

Modifications

Related Issues

Accuracy Test

Benchmark & Profiling

Checklist

• Format your code according to the Code Formatting with Pre-Commit.
• Add unit tests as outlined in the Running Unit Tests.
• Update documentation / docstrings / example tutorials as needed, according to Writing Documentation.
• Provide throughput / latency benchmark results and accuracy evaluation results as needed, according to Benchmark and Profiling and Accuracy Results.
• For reviewers: If you haven't made any contributions to this PR and are only assisting with merging the main branch, please remove yourself as a co-author when merging the PR.
• Please feel free to join our Slack channel at https://sgl-fru7574.slack.com/archives/C09784E3EN6 to discuss your PR.

[gemini-code-assist]

Summary of Changes

Hello @justadogistaken, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request addresses a subtle bug in the validation of the ckpt_dir argument within the model building script. The change improves the robustness of the checkpoint loading mechanism by ensuring that an invalid directory path, when provided, is correctly identified and an appropriate error is raised, leading to more predictable and stable execution.

Highlights

• Checkpoint Directory Validation: The conditional logic for validating the ckpt_dir argument has been refined. This ensures that a ValueError is now correctly raised when a checkpoint directory is explicitly provided but does not exist or is not a valid directory, preventing incorrect behavior in such scenarios.

Using Gemini Code Assist

The full guide for Gemini Code Assist can be found on our documentation page, here are some quick tips.

Invoking Gemini

You can request assistance from Gemini at any point by creating a comment using either /gemini <command> or @gemini-code-assist <command>. Below is a summary of the supported commands on the current page.

Feature	Command	Description
Code Review	/gemini review	Performs a code review for the current pull request in its current state.
Pull Request Summary	/gemini summary	Provides a summary of the current pull request in its current state.
Comment	@gemini-code-assist	Responds in comments when explicitly tagged, both in pull request comments and review comments.
Help	/gemini help	Displays a list of available commands.

Customization

To customize Gemini Code Assist for GitHub experience, repository maintainers can create a configuration file and/or provide a custom code review style guide (such as PEP-8 for Python) by creating and adding files to a .gemini/ folder in the base of the repository. Detailed instructions can be found here.

Limitations & Feedback

Gemini Code Assist may make mistakes. Please leave feedback on any instances where its feedback is incorrect or counter productive. You can react with 👍 and 👎 on @gemini-code-assist comments. If you're interested in giving your feedback about your experience with Gemini Code Assist for Github and other Google products, sign up here.

You can also get AI-powered code generation, chat, as well as code reviews directly in the IDE at no cost with the Gemini Code Assist IDE Extension.

Footnotes

1. Review the Privacy Notices, Generative AI Prohibited Use Policy, Terms of Service, and learn how to configure Gemini Code Assist in GitHub here. Gemini can make mistakes, so double check it and use code with caution. ↩

[gemini-code-assist]

Code Review

This pull request correctly fixes an issue with the checkpoint directory check. Previously, not providing a ckpt_dir would incorrectly raise an error. The new logic properly handles this by only validating the path if it's provided. While reviewing this change, I noticed a critical pre-existing bug within the modified code block where draft_model_config is assigned a string path instead of a configuration object, which would cause the program to crash. I've included a comment with a suggested fix for this issue.

[gemini-code-assist]

There appears to be a type mismatch here. The draft_model_config variable is expected to be an AutoDraftModelConfig object, but it's being assigned a string (a file path). This will likely cause an AttributeError later when this variable is used in functions like build_target_model or build_dataloaders.

To fix this, you should load the configuration from the file path using the AutoDraftModelConfig.from_file method.

Suggested change

	draft_model_config = os.path.join(args.ckpt_dir, "config.json")
	draft_model_config = AutoDraftModelConfig.from_file(os.path.join(args.ckpt_dir, "config.json"))