test: Phase 5 — 24 tests for filterEdited, filterEphemeral, ContextEdit validation

[e6qu]

Phase 5: Remaining Tests

24 new tests covering the core message filtering and context edit validation logic. These test Frankencode-specific features — none of these systems exist in upstream OpenCode.

Origin and Attribution

The features being tested were designed and built entirely for Frankencode. They are not backports — upstream OpenCode has no equivalent context editing, lifecycle markers, or ephemeral command system.

Original design and implementation:

• Adrian Mârza (@e6qu) — designed the context editing architecture (CAS, edit graph, 6 operations, lifecycle markers, deterministic sweeper, ephemeral commands, side threads, focus agents)
• Implementation assistance by Claude (Anthropic) across Phases 0-5 of the Frankencode roadmap

Upstream contributions that informed the design:

• The message pipeline structure (toModelMessages, convertToModelMessages) was designed by the upstream OpenCode team (Dax Raad, Kit Langton) — our filterEdited and filterEphemeral plug into this existing pipeline
• The permission system (PermissionNext) used by ContextEdit validation was originally by Jason Quense (anomalyco/opencode#17064) — we extended it with ownership, budget, and recency rules
• The AsyncLocalStorage context propagation pattern (InstanceALS) used in test fixtures was refactored by Kit Langton (anomalyco/opencode#17544) — we further refactored it into InstanceALS + InstanceLifecycle + InstanceContext

Bug fixes found during implementation (by Frankencode):

• B3: unhide/annotate missing transaction — found and fixed in code review
• B7: filterEdited breaks message alternation — fixed with synthetic placeholder (the exact behavior tested here)
• B15: Ephemeral commands crash (schema validation) — fixed by replacing sweep with filterEphemeral() (tested here)
• B16: Ephemeral sweep leaks content into LLM turn — fixed by upstream filter via filterEphemeral() (tested here)
• B49: context-edit mark() not in transaction — found and fixed in PR fix: bug fixes (B47-B52), type safety audit, architecture docs #22

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filterEdited (8 tests) — test/session/filter-edited.test.ts

Tests for MessageV2.filterEdited() (source).

Pure function tests (no DB):

• No-edit passthrough (identity optimization)
• Hidden part removal (edit.hidden === true)
• Superseded part removal (edit.supersededBy set)
• Parts with edit.hidden === false kept
• Mixed hidden/visible filtering
• Synthetic placeholder on all-hidden message ("[Content edited out]", synthetic: true)
• Message alternation preserved with placeholder (B7 fix)
• Object identity preserved when no filtering needed

filterEphemeral (6 tests) — test/session/filter-ephemeral.test.ts

Tests for MessageV2.filterEphemeral() (source).

Pure function tests (no DB):

• No-ephemeral passthrough
• All-ephemeral message removal
• Partial ephemeral kept (some parts ephemeral, others not)
• Paired assistant removal via parentID link
• User message kept when only assistant is ephemeral
• Multiple ephemeral messages filtered correctly

ContextEdit validation (10 tests) — test/context-edit/validation.test.ts

Tests for validation logic in ContextEdit (source).

Integration tests (DB-backed via Instance.provide):

• Ownership: privileged agent bypass, user message protection, cross-agent block, self-edit
• Budget: under/over 70% hidden ratio
• Recency: last 2 turns protected, older messages editable
• Tool protection: "skill" tool parts blocked
• General: successful hide() returns CAS hash

See docs/context-editing.md for full architecture documentation.

Test plan

• bun run typecheck (tsgo) — 0 errors
• bun test — 1512 pass, 0 fail (24 new)