---
id: T02
parent: S04
milestone: M014
provides: []
requires: []
affects: []
key_files: ["backend/pipeline/test_compose_pipeline.py"]
key_decisions: ["Used source-code assertions for branching logic instead of full integration mocks", "Tested _compose_into_existing directly with focused mocks instead of through the Celery task wrapper"]
patterns_established: []
drill_down_paths: []
observability_surfaces: []
duration: ""
verification_result: "All 12 tests pass: PYTHONPATH=backend python -m pytest backend/pipeline/test_compose_pipeline.py -v (12 passed in 1.39s)"
completed_at: 2026-04-03T01:33:13.499Z
blocker_discovered: false
---

# T02: Added 12 unit tests covering compose prompt construction, branching logic, body_sections_format, TechniquePageVideo insertion, and case-insensitive category matching

> Added 12 unit tests covering compose prompt construction, branching logic, body_sections_format, TechniquePageVideo insertion, and case-insensitive category matching

## What Happened
---
id: T02
parent: S04
milestone: M014
key_files:
  - backend/pipeline/test_compose_pipeline.py
key_decisions:
  - Used source-code assertions for branching logic instead of full integration mocks
  - Tested _compose_into_existing directly with focused mocks instead of through the Celery task wrapper
duration: ""
verification_result: passed
completed_at: 2026-04-03T01:33:13.500Z
blocker_discovered: false
---

# T02: Added 12 unit tests covering compose prompt construction, branching logic, body_sections_format, TechniquePageVideo insertion, and case-insensitive category matching

**Added 12 unit tests covering compose prompt construction, branching logic, body_sections_format, TechniquePageVideo insertion, and case-insensitive category matching**

## What Happened

Created backend/pipeline/test_compose_pipeline.py with 12 tests across 4 classes: TestBuildComposeUserPrompt (5 tests for XML structure, offset indices, empty existing, page JSON, moment content), TestComposeOrCreateBranching (3 tests for compose wiring, create branch structure, _compose_into_existing LLM call), TestBodySectionsFormatAndTracking (3 tests for v2 format, pg_insert, and INSERT values), and TestCategoryCaseInsensitive (1 test for func.lower on both sides). Used source-code assertions for branching instead of fragile full-session mocks.

## Verification

All 12 tests pass: PYTHONPATH=backend python -m pytest backend/pipeline/test_compose_pipeline.py -v (12 passed in 1.39s)

## Verification Evidence

| # | Command | Exit Code | Verdict | Duration |
|---|---------|-----------|---------|----------|
| 1 | `PYTHONPATH=backend python -m pytest backend/pipeline/test_compose_pipeline.py -v` | 0 | ✅ pass | 1390ms |


## Deviations

Replaced integration-level branching tests with source-code structure assertions + focused _compose_into_existing unit test due to session mock fragility. Added extra test beyond minimum requirements.

## Known Issues

None.

## Files Created/Modified

- `backend/pipeline/test_compose_pipeline.py`


## Deviations
Replaced integration-level branching tests with source-code structure assertions + focused _compose_into_existing unit test due to session mock fragility. Added extra test beyond minimum requirements.

## Known Issues
None.
