test(webhook): add Ginkgo/Gomega unit tests for MountPropagationInjector

[Popie52]

Ⅰ. Describe what this PR does

This PR adds a Ginkgo/Gomega-based unit test suite for the MountPropagationInjector webhook plugin.

The existing unit test was implemented using the standard testing.T style and relied on an uninitialized Kubernetes client. This PR refactors the test into a BDD-style Ginkgo/Gomega suite and initializes a proper fake controller-runtime client, making the test behavior safer, clearer, and more representative of real execution paths.

No production code is modified; the change is limited strictly to test code.

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Ⅱ. Does this pull request fix one issue?

fixes #5407

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Ⅲ. List the added test cases (unit test/integration test) if any, please explain if no tests are needed.

Added unit tests (Ginkgo/Gomega):

• Verifies the plugin reports the correct name
• Ensures mutation does not stop when valid runtimeInfo exists
• Ensures mutation succeeds when runtimeInfos is empty
• Ensures mutation returns an error when runtimeInfo is nil

These tests replace the previous testing.T-based test with equivalent coverage and improved structure.

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Ⅳ. Describe how to verify it

Run the following command:

go test ./pkg/webhook/plugins/mountpropagationinjector -v

The test suite should pass successfully without panics or nil-client issues.

Ⅴ. Special notes for reviews

This PR is intentionally scoped as a small, isolated step toward the broader test framework unification effort (Testify / testing.T → Ginkgo/Gomega) discussed in issue #5407.

It demonstrates:

Safe use of controller-runtime fake clients

Coexistence of Ginkgo/Gomega with existing test infrastructure

Improved test readability and structure without impacting production logic

[fluid-e2e-bot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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Once this PR has been reviewed and has the lgtm label, please assign cheyang for approval by writing /assign @cheyang in a comment. For more information see:The Kubernetes Code Review Process.

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[gemini-code-assist]

Summary of Changes

Hello @Popie52, 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 significantly upgrades the unit testing framework for the MountPropagationInjector webhook plugin by migrating its tests from the standard testing.T package to a BDD-style suite using Ginkgo and Gomega. This refactoring improves test readability, reliability, and maintainability by utilizing a properly initialized fake Kubernetes client, ensuring more robust and representative test scenarios without altering any production code.

Highlights

• Ginkgo/Gomega Adoption: Introduces Ginkgo/Gomega unit tests for the MountPropagationInjector webhook plugin, replacing the previous testing.T-style test.
• Improved Test Client: Refactors tests to use a proper fake controller-runtime client, enhancing test safety, clarity, and realism.
• New Test Cases: Adds specific BDD-style tests for MountPropagationInjector covering plugin naming, mutation behavior with and without runtimeInfo, and error handling for nil runtimeInfo.
• No Production Code Impact: Confirms that all changes are confined to test code, with no modifications to production logic.

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[fluid-e2e-bot]

Hi @Popie52. Thanks for your PR.

I'm waiting for a fluid-cloudnative member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

I understand the commands that are listed here.

Details

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[gemini-code-assist]

Code Review

This pull request effectively refactors the unit tests for MountPropagationInjector and FuseSidecar webhook plugins to use Ginkgo/Gomega, which improves readability and structure. The use of a fake controller-runtime client is a significant improvement over the previous nil client, making the tests safer and more realistic.

My review includes suggestions to enhance the test coverage for both plugins to ensure their core mutation logic is actually being tested, which is currently not the case as the test pods lack the necessary volume mounts to trigger the injection logic.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud