Add more tests for FSTree

[End-rey]

Ref #3451.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 22.98%. Comparing base (334de34) to head (fc0f210).
Report is 10 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3473      +/-   ##
==========================================
+ Coverage   22.96%   22.98%   +0.02%     
==========================================
  Files         669      669              
  Lines       50083    50089       +6     
==========================================
+ Hits        11501    11514      +13     
+ Misses      37681    37676       -5     
+ Partials      901      899       -2     

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[Copilot]

Pull Request Overview

This PR refactors the FSTree test code by extracting common functionality into a shared file and adding new comprehensive benchmarks. The main purpose is to reduce code duplication across test files and expand test coverage with additional benchmark scenarios.

Key changes include:

• Creation of a common test utilities file to consolidate shared functions
• Addition of comprehensive benchmarks for Head, Get, and GetStream operations
• Refactoring of existing benchmark tests to use the new shared utilities

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
common_test.go	New file containing shared test utilities and helper functions
bench_test.go	New comprehensive benchmark suite for FSTree operations
head_bench_test.go	Refactored to use common utilities, removed duplicate code
head_test.go	Refactored to use common utilities, moved shared function to common file
range_bench_test.go	Refactored to use common utilities, cleaned up duplicate setup code