# Context Pipeline Testing Strategy & Audit

## Philosophy: Defense in Depth
Our testing strategy avoids the "endless tax" of brittle tests by strictly separating concerns:
1. **Unit Tests (Processors, System Fakes, Mappers):** Exhaustively test logical boundaries, token math, and state transformations. Driven by shared, DRY test factories (no repetitive boilerplate).
2. **Component Tests (ContextManager, Orchestrator):** Test the *wiring* and *triggers*. Verify that barriers block, background pipelines execute, and events fire correctly.
3. **Golden / E2E Tests:** Test emergent behavior. Pass in complex, raw chat histories and assert the exact final projected `Content[]` output against committed JSON snapshots.

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## Audit Checklist & Coverage Tracker

### 1. The Tooling Library (`contextTestUtils.ts`)
- [x] Implement `ContextTestBuilder` or shared factory functions (`createDummyEpisode`, `createDummyState`).
- [x] Ensure all existing tests are migrated to use these helpers to establish the pattern.

### 2. Unit Tests (The Processors & Map/Reduce)
Goal: Ensure every component gracefully handles boundary conditions (budget satisfied vs. deficit), skips protected IDs, and correctly transforms IR.
- [x] `BlobDegradationProcessor` (Completed)
- [x] `ToolMaskingProcessor` (Completed)
- [x] `HistorySquashingProcessor` (Completed)
- [x] `SemanticCompressionProcessor` (Completed)
- [x] `StateSnapshotProcessor` (Completed)
- [x] `EmergencyTruncationProcessor` (Completed)
- [x] `ContextTracer` (Completed)
- [x] `SidecarLoader` (Completed)
- [x] `IrMapper` / `graphUtils` (Completed - Handles Multi-Tool Concurrency and Backwards Graph Traversal)

### 3. Component Tests (The Orchestration)
Goal: Prove the sidecar configuration accurately drives runtime behavior without testing the processor logic itself.
- [x] `PipelineOrchestrator`: Test sync vs. async routing, error swallowing, and trigger setup.
- [ ] `ContextManager`: Test `subscribeToHistory` (Opportunistic triggers).
- [ ] `ContextManager`: Test `project()` (Synchronous barrier triggers).

### 4. Golden / E2E Tests
- [ ] `contextManager.golden.test.ts`: Ensure we have a scenario representing a "Day in the Life" of the CLI (some images, some huge tool outputs, deep history) mapping to a snapshot.

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## Next Actions
1. Audit the ContextManager component tests (opportunistic updates & sync barrier).
2. Finalize the End-to-End "Day in the Life" Golden Snapshot test.