fix(tokens): l-03 tokens uris presist accross burn and remint

[0xisk]

Types of changes

What types of changes does your code introduce to OpenZeppelin Midnight Contracts?
Put an x in the boxes that apply

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update (if none of the other choices apply)

Fixes #427

PR Checklist

• I have read the Contributing Guide
• I have added tests that prove my fix is effective or that my feature works. See GUIDELINES.md#testing for more information.
• I have added documentation for new methods or changes to existing method behavior. See GUIDELINES.md#documentation for more information.
• CI Workflows Are Passing

Further comments

If this is a relatively large or complex change, kick off the discussion by explaining why you chose the solution you did and what alternatives you considered, etc...

Summary by CodeRabbit

• Bug Fixes

  • Token burning now properly removes associated metadata, ensuring complete cleanup when tokens are destroyed.

• Tests

  • Added test validation confirming that stored metadata is correctly cleared when tokens are burned and reminted.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 7f296440-318e-445e-9f88-47c9ff90fed7

📥 Commits

Reviewing files that changed from the base of the PR and between 25aa666 and dc3c679.

📒 Files selected for processing (2)

• contracts/src/token/NonFungibleToken.compact
• contracts/src/token/test/nonFungibleToken.test.ts

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Walkthrough

The pull request fixes a token URI persistence issue by updating the _burn() function to delete stored token URIs when tokens are burned, preventing stale metadata from being inherited by reminted tokens. A corresponding test verifies this behavior.

Changes

Cohort / File(s)	Summary
NFT Burn Logic contracts/src/token/NonFungibleToken.compact	Added deletion of _tokenURIs entry in _burn() to prevent URI persistence after token burn.
Burn Test Coverage contracts/src/token/test/nonFungibleToken.test.ts	Added test case verifying that burning a token clears its stored URI, with token remint confirming the URI is empty.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

Poem

🐰 A token burns, its memory too—
No stale URIs haunting what's new,
Fresh mint, clean slate, the old is gone,
In Compact's flame, we move along! ✨

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately describes the main fix: clearing token URIs on burn to prevent persistence across burn and remint cycles.
Linked Issues check	✅ Passed	The PR successfully implements the core requirement from issue #427: clearing the stored token URI when a token is burned, and includes a test verifying the fix.
Out of Scope Changes check	✅ Passed	All changes are directly scoped to fixing issue #427; the contract modification clears URIs on burn and the test validates this behavior without extraneous modifications.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/l-03

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[andrew-fleming]

LGTM!