🧹 chore: add unit tests for reuseRouteBucket

[ric03uec]

Summary

• Adds direct unit tests for the unexported reuseRouteBucket function introduced in 292b40f, which previously had zero test coverage.

Details

reuseRouteBucket is called during buildTree to reuse slice backing arrays across route rebuilds, reducing allocations. The function had no direct tests. It was only exercised indirectly through integration-level router tests.

This adds 4 subtests covering all branches:

Case	Behavior
Key exists, capacity sufficient	Reuses existing backing array (bucket[:0])
Key exists, capacity insufficient	Allocates new slice with requested capacity
Key missing from map	Allocates new slice with requested capacity
Nil map	Allocates new slice with requested capacity

Checklist

• make audit - pass (stdlib-only vulns, unrelated)
• make generate - pass
• make betteralign - pass
• make modernize - pass
• make format - pass
• make lint - pass
• make test - 2680 passed, 0 failed
• Tests use t.Parallel() per project conventions
• No documentation changes needed (internal unexported function)

[gemini-code-assist]

Summary of Changes

Hello @ric03uec, 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 robustness and reliability of the router component by providing dedicated unit tests for the reuseRouteBucket function. This function is crucial for memory optimization, and the new tests ensure its correct behavior across various scenarios, thereby improving the overall stability and performance of the routing mechanism.

Highlights

• Unit Test Coverage: Added direct unit tests for the previously unexported and untested reuseRouteBucket function, which plays a critical role in optimizing memory allocation within the router by reusing slice backing arrays.
• Comprehensive Test Cases: Introduced four distinct subtests within Test_reuseRouteBucket to cover all expected branches: reusing an existing bucket with sufficient capacity, allocating a new bucket when capacity is insufficient, allocating a new bucket when the key is missing, and allocating a new bucket when the prev map is nil.

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Changelog

• router_test.go
  • Added a new test function Test_reuseRouteBucket to provide direct unit test coverage for the reuseRouteBucket utility function.
  • Implemented four subtests within Test_reuseRouteBucket to validate the function's behavior under different conditions: sufficient capacity, insufficient capacity, missing key, and a nil prev map.
  • Ensured all new tests adhere to project conventions by running in parallel using t.Parallel().

Activity

• The pull request was created by ric03uec.
• No review comments or additional activity have been recorded yet.

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[coderabbitai]

Walkthrough

The PR adds unit tests for the reuseRouteBucket function to verify its bucket allocation and reuse behavior under various conditions, including capacity checks, new allocations, and nil map handling.

Changes

Cohort / File(s)	Summary
Router Tests router_test.go	Added test cases for reuseRouteBucket function covering capacity reuse scenarios, new bucket allocations when capacity is insufficient, missing keys, and nil map conditions.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Possibly related PRs

• ⚡ perf: Improve performance of RebuildTree() by 68% #3895: Directly related to route bucket allocation and preallocation logic changes that these tests verify.

Suggested reviewers

• sixcolors
• efectn
• ReneWerner87

Poem

🐰 A bucket reused, a capacity kept,
Tests written neatly, no corners are slept,
Nil maps and edges, all cases explored,
Routes optimized, and memory restored! ✨

🚥 Pre-merge checks | ✅ 2 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Description check	✅ Passed	The PR description covers key aspects including summary, details, all test cases, and a thorough checklist of validation steps. It meets the repository's template requirements for test-focused changes.
Title check	✅ Passed	The title accurately describes the main change: adding unit tests for reuseRouteBucket. The emoji is stylistic but acceptable; the core message is clear and specific.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing touches

• 📝 Generate docstrings

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment

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[gemini-code-assist]

Code Review

This pull request adds valuable unit tests for the reuseRouteBucket function, which previously lacked direct test coverage. The tests are well-structured and cover all the essential logic branches, including reuse with sufficient capacity, allocation with insufficient capacity, handling of missing keys, and nil maps. My review includes a couple of suggestions to make the tests even more robust by explicitly verifying whether the slice's backing array is reused or reallocated, which is the core purpose of this function.

[gemini-code-assist]

While checking the capacity is good, this test doesn't explicitly verify that the underlying array of the slice is being reused. A more robust test would assert that the pointer to the backing array is the same for the original and the returned slice. This ensures the function behaves as expected regarding memory reuse.

		require.Equal(t, 10, cap(got))
		require.Equal(t, reflect.ValueOf(existing).Pointer(), reflect.ValueOf(got).Pointer(), "backing array should be reused")

[gemini-code-assist]

This test correctly checks that a new slice is allocated with the correct capacity. To make it more robust, you could also assert that the new slice does not share the same underlying array as the original slice. This would explicitly confirm that a new allocation occurred, as intended.

		require.Equal(t, 5, cap(got))
		require.NotEqual(t, reflect.ValueOf(existing).Pointer(), reflect.ValueOf(got).Pointer(), "new backing array should be allocated")

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.03%. Comparing base (5913370) to head (8338938).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #4069   +/-   ##
=======================================
  Coverage   91.03%   91.03%           
=======================================
  Files         119      119           
  Lines       11243    11243           
=======================================
  Hits        10235    10235           
  Misses        637      637           
  Partials      371      371           

Flag	Coverage Δ
unittests	91.03% <ø> (ø)

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[gaby]

@ric03uec The coverage report is showing a 0.00% change. These tests are not adding new coverage.

[ric03uec]

@ric03uec The coverage report is showing a 0.00% change. These tests are not adding new coverage.
my bad. should've checked the coverage delta. i missed that this was being tested indirectly with existing ITs. thanks for the quick feedback. closing this PR