Add unit tests for /pkg/controller/netns/netns.go

[adity1raut]

Description

This PR adds comprehensive unit test coverage for the pkg/controller/netns package to improve code quality and maintainability.

Fixed Isuue #1540

Changes

• ✅ Added netns_test.go with comprehensive test coverage
• ✅ Fixed linting issue: uncapitalized error message in FindNetnsForPod
• ✅ Implemented table-driven tests for all public and helper functions
• ✅ Added mock filesystem support using fstest.MapFS
• ✅ Created mock DirEntry implementation for testing

Test Coverage

The new tests cover:

• GetNodeNSpath() - Node namespace path generation
• GetPodNSpath() - Pod namespace path retrieval
• builtinOrDir() - Filesystem selection logic
• isNotNumber() - Character validation helper
• isProcess() - Process directory identification
• processEntry() - Entry processing with mocked filesystem
• FindNetnsForPod() - Main pod namespace discovery function

Files Changed

• pkg/controller/netns/netns_test.go - New comprehensive test suite

Why This Matters

• Improved Code Quality: Better test coverage helps catch regressions early
• Documentation: Tests serve as usage examples for the package
• Maintainability: Makes refactoring safer and easier
• CI/CD Ready: Automated testing can be integrated into build pipelines

Checklist

• Tests pass locally
• All linting errors resolved
• Code follows project style guidelines
• Documentation updated (test comments)
• No breaking changes

[gemini-code-assist]

Summary of Changes

Hello @adity1raut, 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 enhances the quality and maintainability of the pkg/controller/netns package by introducing extensive unit test coverage. The new tests validate the behavior of key functions related to network namespace discovery and path generation, ensuring greater reliability and easier future refactoring. Additionally, it addresses and resolves several existing linting issues.

Highlights

• New Unit Tests: Added a comprehensive unit test suite in netns_test.go for the pkg/controller/netns package, covering all public and helper functions.
• Table-Driven Tests: Implemented table-driven tests for improved readability and maintainability of test cases.
• Mock Filesystem Support: Incorporated fstest.MapFS and a custom mockDirEntry to simulate filesystem interactions, enabling robust testing without actual file operations.
• Linting Fixes: Resolved several linting issues, including uncapitalized error messages (ST1005), unhandled os.RemoveAll errors (errcheck), and suppressed an unused warning.

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A test file new, a bug takes flight, Code now robust, shining bright. With mocks and maps, paths defined, No more errors, peace of mind.

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[gemini-code-assist]

Code Review

This pull request introduces a comprehensive suite of unit tests for the netns package, which is a valuable addition for improving code quality and maintainability. The use of table-driven tests and fstest.MapFS for mocking is a good approach. However, my review has identified several critical issues where tests are either incomplete or designed to fail, which undermines their purpose. Key functions like FindNetnsForPod and GetPodNSpath are missing tests for their success paths, and some mocks are insufficient for the code they are intended to test. Additionally, an edge case in the isProcess function is handled incorrectly. I have provided specific feedback on how to address these points to ensure the test suite is robust and effectively validates the package's functionality.

[codecov]

Codecov Report

❌ Patch coverage is 25.00000% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 39.31%. Comparing base (6d531a8) to head (b85e001).
⚠️ Report is 23 commits behind head on main.

Files with missing lines	Patch %	Lines
pkg/controller/netns/netns.go	25.00%	2 Missing and 1 partial ⚠️

Files with missing lines	Coverage Δ
pkg/controller/netns/netns.go	63.63% <25.00%> (+63.63%)	⬆️

... and 3 files with indirect coverage changes

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[Copilot]

Pull request overview

This PR adds comprehensive unit test coverage for the pkg/controller/netns package, implementing table-driven tests for all public functions and helper utilities that manage network namespace paths for Kubernetes pods.

Key Changes:

• Added netns_test.go with 7 test functions covering the public API and internal helper functions
• Created mock filesystem support using fstest.MapFS and custom mockDirEntry implementation
• Implemented table-driven test patterns consistent with the codebase conventions

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[adity1raut]

@hzxuzhonghu
Can You Tack a Look On This PR Thank You

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 11 comments.

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[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 7 comments.

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[adity1raut]

@hzxuzhonghu Can You tack a Look This PR Ready TO merge

[hzxuzhonghu]

/lgtm

[kmesh-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: hzxuzhonghu

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Details

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• pkg/controller/OWNERS [hzxuzhonghu]

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