yoloyolo/.planning/milestones/v1.2-phases/08-test-and-constant-cleanup/08-CONTEXT.md

Phase 8: Test and Constant Cleanup - Context

Gathered: 2026-03-27 Status: Ready for planning

## Phase Boundary

Remove stale exported constants (NumLayers, GainPerLayer) from the synth package and update hardcoded test assertions (TestFrequenciesInRange) so that subsequent v1.2 phases can add new traffic classes and frequencies without triggering false CI failures. This is pure cleanup — no new features, no new protocols.

## Implementation Decisions

Constant Removal Strategy

• D-01: Delete NumLayers and GainPerLayer constants entirely from synth/config.go. They are dead code — NewBank already computes gainPerLayer dynamically as 1.0 / float64(len(cfgs)) (bank.go:21). No external callers reference either constant outside the test file.

Frequency Range Test Bounds

• D-02: Replace the hardcoded [60, 1100] bounds in TestFrequenciesInRange with dynamic validation — derive the valid range from the ClassFreqConfigs data itself (e.g., check that all frequencies are positive and below Nyquist) rather than hardcoding a new magic number that would need manual updating when Phase 9/10 add classes above 1100 Hz. The specific approach (positive+Nyquist check, or a generous static bound like [20, 8000]) is at Claude's discretion — the key constraint is that adding a new class in the 1100-4000 Hz range must not require editing this test.

Test Naming

• D-03: Rename TestNumLayersMatchesAllClasses to TestClassFreqConfigsMatchAllClasses (or similar) to reflect the actual invariant being tested after NumLayers removal. The test body already uses len(synth.ClassFreqConfigs) and len(classify.AllClasses()) — only the name references the deleted constant.

Claude's Discretion

• Whether to use a generous static upper bound vs a computed Nyquist-based bound for D-02 — either approach satisfies the constraint
• Whether WhisperFloor or other constants in config.go need any adjustment (they don't reference NumLayers, so likely no)
• Whether TestClassFreqConfigsComplete (line 53) should be consolidated with the renamed test since both verify the same invariant

Folded Todos

• "Expand Traffic Classes" (from .planning/todos/pending/001-expand-traffic-classes.md) — This todo requests adding protocols like IMAP, POP3, SNMP, FTP and researching common traffic classes. Phase 8 enables this work by removing the test/constant blockers, but the actual protocol additions are Phase 10's scope. Folded here as context, not as direct Phase 8 work.

<canonical_refs>

Canonical References

Downstream agents MUST read these before planning or implementing.

Synth Package (primary targets)

• synth/config.go — Contains NumLayers and GainPerLayer constants to remove (lines 9-10)
• synth/config_test.go — Contains TestFrequenciesInRange (lines 18-24), TestNumLayersMatchesAllClasses (lines 61-66), and TestClassFreqConfigsComplete (lines 53-59)
• synth/bank.go — NewBank already computes gainPerLayer dynamically (line 21) — confirms constants are dead code

Research Context

• .planning/research/PITFALLS.md — Pitfall C4 documents TestFrequenciesInRange hardcoding issue
• .planning/research/ARCHITECTURE.md — Lines 414+ document NumLayers/ClassFreqConfigs mismatch risk
• .planning/research/SUMMARY.md — Lines 69, 85, 100 describe Phase 8 cleanup scope

</canonical_refs>

<code_context>

Existing Code Insights

Reusable Assets

• synth/bank.go:NewBank already has the correct dynamic gain computation — no new code needed for gain behavior

Established Patterns

• Test file synth/config_test.go uses table-driven validation against ClassFreqConfigs map and classify.AllClasses() — new/renamed tests should follow this pattern
• GainPerLayer constant at line 10 has a comment referencing "D-10" — cleanup should not leave orphan decision references

Integration Points

• Only synth/config.go and synth/config_test.go are modified — no downstream package changes expected
• go test ./... is the verification gate — must pass with zero new failures

</code_context>

## Specific Ideas

No specific requirements — this is a straightforward cleanup phase with clear targets identified in research.

## Deferred Ideas

Reviewed Todos (not folded)

None — the matched todo was folded as milestone context.

None — discussion stayed within phase scope.

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Phase: 08-test-and-constant-cleanup Context gathered: 2026-03-27