Fix ModuleDB reporting wrong path when transient dependency cannot find the correct import

[lynzrand]

Consider the following package structure:

Module user/transient:
  Package user/transient/lib:
    depends user/transient/nonexistant;

Module user/main:
  depends user/trainsint;

  Package user/main:
    depends user/transient/lib;

There is an non-existant package dependency at user/transient/lib. Currently, the error will be noticed by moonbuild, but the error was reported using the relative path of the error package, but rooted at SOURCE_PATH, i.e. user/main/lib (a non-existant file). This PR corrects the behavior by reporting the error in the correct place, user/transient/lib.

Related Issues

• Related issues: #____

Type of Pull Request

• Bug fix
• New feature
  • I have already discussed this feature with the maintainers.
• Refactor
• Performance optimization
• Documentation
• Other (please describe):

Does this PR change existing behavior?

• Yes (please describe the changes below)
  • Corrected the output message
• No

Does this PR introduce new dependencies?

• No
• Yes (please check binary size changes)

Checklist:

• Tests added/updated for bug fixes or new features
• Compatible with Windows/Linux/macOS

[peter-jerry-ye-code-review]

‼️ This code review is generated by a bot. Please verify the content before trusting it.

Here are three observations from the git diff output:

1. Missing Newline at End of File:

   • In the file nonexistent_package.in/README.md, there is no newline at the end of the file. This is indicated by the \ No newline at end of file comment. While this is not a bug, it is generally considered good practice to include a newline at the end of files to avoid potential issues with certain tools and version control systems.

2. Inconsistent Error Message Formatting:

   • In the test_nonexistent_package test case, the error messages in the expect! macro are formatted with $ROOT as a placeholder. However, the actual error messages in the code (in crates/moonutil/src/module.rs) do not use $ROOT. This inconsistency could lead to confusion or mismatches between expected and actual error messages. Ensure that the test expectations align with the actual error message format.

3. Potential Redundant Code:

   • In crates/moonutil/src/module.rs, the error message formatting was simplified by replacing a more complex path construction with pkg.root_path.join(MOON_PKG_JSON).display(). While this is a good simplification, ensure that pkg.root_path is always correctly set and points to the intended directory. If pkg.root_path is not properly initialized, this change could introduce bugs.

These observations should be reviewed and addressed to ensure code quality and consistency.