test: static schema-drift gate against the v1.8.0 setup.sql (GIT-109 step 2)

[nTEG-dev]

What

A static gate: nothing src/ reads or writes may be missing from the v1.8.0 setup.sql unless it's allowlisted against the ticket that owns it (GIT-109 step 2).

• tests/helpers/schema-drift.ts does two things.

  • Schema: parses setup.sql into table → columns, covering CREATE TABLE, ALTER … ADD COLUMN and views.
  • Code: walks src/ with the TypeScript compiler API, collecting:
    • writes: table + payload keys reaching directUpsert, directPatch, upsertRecord, storage.upsert;
    • reads: table + select / filter / order keys reaching directQuery, directQueryAll, listRecords, getRecord.

  It follows getTableName("x"), const indirection, spreads and conditional spreads (...(ok && {col})), later row.col = … assignments, local functions' return {…}, and .map / .filter element shapes. Code under if (!hasSupabase()), the else of if (hasSupabase()), or a …Free function writes local JSON and is set aside. Anything it can't resolve is reported as unresolved, never assumed fine.

• tests/fixtures/schema/setup-v1.8.0.sql: the floor, byte-identical to git show v1.8.0:schema/setup.sql. Findings are labelled "added after 1.8.0" or "in no setup.sql" by comparing with the current schema/setup.sql.

• tests/unit/schema-drift.test.ts fails on:

  • a finding that isn't allowlisted;
  • an allowlist entry that no longer matches, so the list only shrinks;
  • an entry without a GIT-### ticket;
  • a new unresolved call site, so coverage can't quietly decay;
  • a SESSION_COLUMNS entry that v1.8.0 lacks and that isn't production-only. That covers session_close's payload, which is built dynamically.

  It also plants drift in a synthetic source tree every run, to prove the analyzer still catches each kind.

First run: everything it found

74 call sites, 362 column accesses; 7 free-tier-only sites set aside; 6 pass-through helpers (the table is a parameter: storage.ts ×3, store-columns.ts, supabase-client.ts ×2; their callers are checked).

11 findings, all in no setup.sql at all (none were added after 1.8.0):

Table / column	Kind	Where	Why it's allowed
gitmem_learnings.archived_at	write	archive-learning.ts:132	GIT-109: probe-guarded, written only if supportedColumns() finds it
gitmem_sessions.claude_code_session_id	write	session-close.ts:1470	GIT-109: production-only, dropped by filterToStoreSessionColumns()
gitmem_sessions.task_observations	write	absorb-observations.ts:75	GIT-109: probe-guarded
variant_assignments (table)	read	variant-assignment.ts:100, 139	GIT-106: dev tier only (hasVariants())
variant_performance_metrics (table)	write	recall.ts:607	GIT-106
scar_enforcement_variants.active	filter + write	variant-assignment.ts:69, variant-generation.ts:322	GIT-106
scar_enforcement_variants.description, .enforcement_config, .variant_name, .variant_version	write	variant-generation.ts:322	GIT-106

Worth knowing: setup.sql creates scar_enforcement_variants, but with a different shape (variant_type, variant_config, metadata) from the one the code reads and writes. It's unreachable on pro and free (GIT-106), but if variants ever leave the dev tier, the table setup.sql provisions won't work with them.

No other drift. Every other table and column reached from src/ exists in v1.8.0.

Unresolved (5 sites; the test pins them, so a new one fails):

• thread-supabase.ts:393, 433, 821: filters come from buildScopedThreadQuery() in another file (thread-scope tests pin them);
• write-health.ts:72: loops over getTableName("learnings" | "decisions") and selects id only;
• session-close.ts:1470: sessionData is narrowed to SESSION_COLUMNS, which the last check compares with v1.8.0.

All Release C branches scanned too (#37–#45): each has exactly the same 11 findings and no new unresolved sites. None of this release's fixes reaches a column a v1.8.0 store lacks.

How to test

npx vitest run tests/unit/schema-drift.test.ts: 9/9. Full suite 1283/1283 (+9).

Negative control on real code: adding drift_probe_column: 1 to create_decision's payload fails the gate with gitmem_decisions.drift_probe_column [write] (in no setup.sql) at src/tools/create-decision.ts:87. Reverted.

Venue: not applicable. This is a static test; nothing runs against a store.

Checklist

• npm run test:unit passes (1283)
• Planted-drift self-test and a real negative control
• No schema change
• Docs: n/a

Breaking changes

None. Test only.

🤖 Generated with Claude Code