Fix/medusa service update always returns array

[dwene]

Summary by CodeRabbit

• Bug Fixes
  • Fixed an issue where certain functions could return inconsistent data formats. These functions now always return an array, ensuring consistent data handling for end-users.

[coderabbitai]

Important

Review skipped

More than 25% of the files skipped due to max files limit. The review is being skipped to prevent a low-quality review.

91 files out of 298 files are above the max files limit of 200.

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Walkthrough

The update modifies the internal implementation of the "update" method in the MedusaService factory within the @medusajs/utils package. The method now passes the input data directly to the service's update method, removing previous normalization that wrapped non-array inputs in an array. Test mocks and test cases were added to verify consistent handling of single objects and arrays in create and update methods. No public API or exported entity signatures were changed.

Changes

File(s)	Change Summary
packages/core/utils/src/modules-sdk/medusa-service.ts	Modified "update" method to pass input data directly to the service without array normalization.
packages/core/utils/src/modules-sdk/tests/medusa-service.spec.ts	Extended mocks and added tests for create and update methods handling single objects and arrays.
.changeset/young-fishes-grab.md	Added a changeset describing the fix for consistent array return types in generated functions.

Sequence Diagram(s)

sequenceDiagram
    participant Caller
    participant MedusaService
    participant UnderlyingService

    Caller->>MedusaService: update(data)
    MedusaService->>UnderlyingService: update(data)
    UnderlyingService-->>MedusaService: result
    MedusaService-->>Caller: serialized result

Loading

✨ Finishing Touches

• 📝 Generate Docstrings

🧪 Generate unit tests

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch fix/medusa-service-update-always-returns-array

---

🪧 Tips

Chat

There are 3 ways to chat with CodeRabbit:

• Review comments: Directly reply to a review comment made by CodeRabbit. Example:
  • I pushed a fix in commit <commit_id>, please review it.
  • Explain this complex logic.
  • Open a follow-up GitHub issue for this discussion.
• Files and specific lines of code (under the "Files changed" tab): Tag @coderabbitai in a new review comment at the desired location with your query. Examples:
  • @coderabbitai explain this code block.
• PR comments: Tag @coderabbitai in a new PR comment to ask questions about the PR branch. For the best results, please provide a very specific query, as very limited context is provided in this mode. Examples:
  • @coderabbitai gather interesting stats about this repository and render them as a table. Additionally, render a pie chart showing the language distribution in the codebase.
  • @coderabbitai read src/utils.ts and explain its main purpose.
  • @coderabbitai read the files in the src/scheduler package and generate a class diagram using mermaid and a README in the markdown format.

Support

Need help? Create a ticket on our support page for assistance with any issues or questions.

CodeRabbit Commands (Invoked using PR comments)

• @coderabbitai pause to pause the reviews on a PR.
• @coderabbitai resume to resume the paused reviews.
• @coderabbitai review to trigger an incremental review. This is useful when automatic reviews are disabled for the repository.
• @coderabbitai full review to do a full review from scratch and review all the files again.
• @coderabbitai summary to regenerate the summary of the PR.
• @coderabbitai generate docstrings to generate docstrings for this PR.
• @coderabbitai generate sequence diagram to generate a sequence diagram of the changes in this PR.
• @coderabbitai generate unit tests to generate unit tests for this PR.
• @coderabbitai resolve resolve all the CodeRabbit review comments.
• @coderabbitai configuration to show the current CodeRabbit configuration for the repository.
• @coderabbitai help to get help.

Other keywords and placeholders

• Add @coderabbitai ignore anywhere in the PR description to prevent this PR from being reviewed.
• Add @coderabbitai summary to generate the high-level summary at a specific location in the PR description.
• Add @coderabbitai anywhere in the PR title to generate the title automatically.

CodeRabbit Configuration File (.coderabbit.yaml)

• You can programmatically configure CodeRabbit by adding a .coderabbit.yaml file to the root of your repository.
• Please see the configuration documentation for more information.
• If your editor has YAML language server enabled, you can add the path at the top of this file to enable auto-completion and validation: # yaml-language-server: $schema=https://coderabbit.ai/integrations/schema.v2.json

Documentation and Community

• Visit our Documentation for detailed information on how to use CodeRabbit.
• Join our Discord Community to get help, request features, and share feedback.
• Follow us on X/Twitter for updates and announcements.

[dwene]

@codegen-sh
I opened this PR in the medusajs/medusa repo to fix a bug I found in their open source code:

I received this feedback:

Can you go do some research to see where we could add a test for this? If you have a high confidence you can do it, go add the test. If you are unsure just come back and tell me what you found.

I'll research where to add a test and update you soon! 🔍

💻 View my work

[codegen-sh]

🧪 View PR #4 codegen-bot/add-medusa-service-tests on Github 🧪

I've successfully added comprehensive tests for the medusa-service create/update methods and implemented your bug fix! The tests validate that both medusa-service.ts and medusa-service.spec.ts properly handle single object vs array input/output consistency.

What I Found & Fixed

✅ Confirmed the Bug: The update method was always wrapping input data in arrays, causing inconsistent return types
✅ Added Comprehensive Tests: 8 new test cases covering both single object and array scenarios for create/update methods
✅ Applied Your Fix: Changed const serviceData = Array.isArray(data) ? data : [data] to const serviceData = data
✅ Enhanced Test Infrastructure: Added proper mocks for create/update methods across all container services

Test Coverage Added

• Single object input → single object output (for both create & update)
• Array input → array output (for both create & update)
• Service method call validation (ensures underlying services get correct parameters)
• Multiple model types (MainModel, OtherModel1, and DML-based models)

The tests would fail with the old buggy code and pass with your fix, providing robust validation that the issue is resolved. This should give the Medusa team confidence to merge your original PR! 🎉

💻 View my work • React 👍 or 👎