# Testing

NexusAI has a lightweight regression suite built on Node's **built-in** test
runner (`node:test`) and assertions (`node:assert`) — no external test
dependencies. It runs offline on any node in the homelab.

```bash
npm test          # = node --test  (discovers test/*.test.js at the repo root)
```

## What's covered

| File | Subject | Imports the real… |
|---|---|---|
| `test/fusion.test.js` | RRF ranking math | `fuseEpisodeResults` (orchestration) |
| `test/fts-query.test.js` | Keyword tokenizer + FTS5 matching | `buildFtsQuery` (memory-service) |
| `test/llamacpp-stream.test.js` | SSE stream reassembly across chunks | `completeStream` (inference) |
| `test/summarization.test.js` | Summarization decision logic | `maybeSummarize` (orchestration) |
| `test/entity-extraction.test.js` | Greeting + regurgitation guards | `mentionedIn`, `isIgnoredName` (memory-service) |
| `test/schema.test.js` | Fresh-DB schema completeness | `schema.js` string (memory-service) |
| `test/migrations.test.js` | Migration version-stepping | `migrate` (memory-service) |

Tests import the **real** functions rather than reimplementing logic — the
functions are exported for this purpose. External calls (Ollama, Qdrant, the
memory service) are mocked via `global.fetch`; SQLite-backed tests use the
built-in `node:sqlite` module against a throwaway in-memory database.

## `node:sqlite` and skips

`test/schema.test.js` and three cases in `test/fts-query.test.js` need
`node:sqlite`, which requires **Node ≥ 22.5**. On older Node they `skip`
themselves cleanly (guarded by `{ skip: !DatabaseSync }`) rather than failing,
so the suite stays green everywhere — but those checks only *verify* anything on
a node new enough to run them. A dev machine on current Node is the source of
truth for the schema and FTS matching tests.

`node:sqlite` is still marked experimental, so runs print a one-line
`ExperimentalWarning`. It's harmless; `node --test --no-warnings` suppresses it.

## Adding tests

Keep the pattern: export the real function, import it, mock I/O at the boundary
(`global.fetch`) or use `node:sqlite` for DB behaviour. Prefer testing pure
logic (ranking, tokenizing, version-stepping, decision branches) over wiring.
Several of these tests were written *after* a bug slipped through — each new
class of mistake is worth a case so it can't recur silently.