⚡ Optimize FileList#first_seen_at to eliminate allocations#622
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Replaced the `filter_map` implementation with an `each`-based loop to calculate the minimum `first_updated_at` timestamp. This eliminates intermediate array allocations (reducing memory usage from ~89KB to 0 bytes for 10k items) while maintaining comparable CPU performance. Added a benchmark script `test/benchmarks/benchmark_file_list.rb` to verify the improvement. Co-authored-by: danmayer <24925+danmayer@users.noreply.github.com>
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💡 What: Replaced the
filter_mapimplementation inCoverband::Utils::FileList#first_seen_atwith an imperativeeachloop to find the minimumfirst_updated_attimestamp.🎯 Why: The previous implementation (and the one suggested in the task description) allocated intermediate arrays. Even
filter_map, while efficient, creates a new array. By usingeachand tracking the minimum value manually, we eliminate these allocations entirely.📊 Measured Improvement:
Benchmark results for 10,000 files:
map+reject): ~169 KB allocatedfilter_map): ~89 KB allocatedeach): 0 bytes allocatedCPU performance is comparable (slightly faster in some runs, but within margin of error). This change significantly reduces memory pressure for large file lists.
PR created automatically by Jules for task 3731001549367096294 started by @danmayer