backend: k8cache: add update and delete coverage to informer tests

[ChayanDass]

Summary

This PR expands backend test coverage for the experimental k8cache by validating cache invalidation on Add, Update, and Delete informer events. Previously, tests exercised only Add events; this change ensures Update/Delete handlers are also covered and behave correctly.

Related Issue

Fixes the review feedback on backend cache invalidation tests from PR

• backend: k8cache: Add experimental cache #3740.

Fixes #4506

• backend: cacheInvalidation_test: TestRunInformerToWatch: Add tests for Update and Delete as well #4506

[k8s-ci-robot]

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[Copilot]

Pull request overview

This PR enhances the test coverage for the experimental k8cache package by adding tests for Update and Delete informer events. Previously, the TestRunInformerToWatch test only covered Add events; this change ensures that cache invalidation works correctly for all three event types (Add, Update, and Delete).

Changes:

• Added eventType field to test case structure to distinguish between add, update, and delete events
• Added two new test cases: one for update events and one for delete events
• Implemented event-specific logic in a switch statement to trigger the appropriate Kubernetes client operations for each event type
• Fixed variable naming (schema → scheme) for consistency with Go conventions
• Added necessary imports (context and metav1)

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[illume]

Thanks!

The GitHub check is failing on a lint issue. You can run lint locally...

npm run backend:lint
npm run backend:format
npm run backend:test

Please consider the open review comment?

[ChayanDass]

@illume The lint error was from dupl due to structurally duplicated test data. Changing values didn’t help, so I refactored the shared data into a common fixture/struct.
Please take a look and let me know if it looks good to you , i will squash all my commits .

[illume]

@ChayanDass

Thanks for that.

Did you look at the coverage report?

npm run backend:coverage:html
# To just print a simpler coverage report to the console.
npm run backend:coverage

[illume]

Can you please squash your commits?

[ChayanDass]

Done!

[illume]

Thanks for that.

Just wondering if you could confirm that this is covering the code paths as you expected by looking at the test coverage report?

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Some nits on the git commit message for the future (feel free to ignore for this PR)

• We don't need "Signed-off-by" in this repo, because it uses the CLA.
• We capitalise the imperative mood verb at the start, because it's like a normal subject line

[ChayanDass]

before -> 50%
After -> 75%

[ChayanDass]

Is the current test coverage okay, or should I add more tests to increase coverage further?

[illume]

Seems pretty good. If you look at the html view you can see which code paths are not covered by tests.