test: remove unnecessary ±1 tolerance in blackbox tests

[JustinDFuller]

Note: This PR title, description, and code were generated with Claude Code

Summary

• Removed the ±1 tolerance from call count assertions in blackbox tests
• Tests pass without any failures, confirming the algorithm's precision

Background

The blackbox tests had a tolerance allowing call counts to be off by ±1:

if expected := int(1000 * (float64(second.flowRate) / 100)); calls-expected > 1 || calls-expected < -1

This tolerance appeared to be defensive coding to handle potential rounding errors in the flow control algorithm.

Analysis

After investigation, the flow control algorithm is mathematically precise:

• Uses cumulative allowed and blocked counters
• Calculates allowRate = (allowed * 100) / total
• Makes deterministic allow/block decisions based on allowRate < flowRate

This creates a self-correcting feedback loop that naturally converges to the exact target rate.

Test Results

Both blackbox tests pass without any failures after removing the tolerance:

• TestNozzleDoBoolBlackbox - PASS (68 seconds)
• TestNozzleDoErrorBlackbox - PASS (61 seconds)

All flow rates (100%, 99%, 97%, down to 0%) produce exactly the expected number of calls.

Conclusion

The ±1 tolerance was unnecessary. The algorithm produces exact results, making this defensive code removable.

🤖 Generated with Claude Code