cto/.sot/03-PROTOCOLS/CTO-CASE-FAILURE-FIXTURE-MATRIX.md

name	tier	status	owner	source	created	last_reviewed	lifecycle_classification	core_promotion_status	description
cto-case-failure-fixture-matrix	local	draft	jp	.sot/03-PROTOCOLS/CTO-CASE-CANDIDATE-BACKEND-PRD.md	2026-05-31	2026-05-31	planning	not-promoted	Child-local failure fixture matrix for later Case adapter fail-closed testing.

CTO Case Failure Fixture Matrix

Local planning SOT only. Not a Core Protocol. Not active Core authority.

Purpose

Define the required failure fixtures for later Case adapter testing before any executable Case integration exists.

This matrix turns failure-mode language into concrete expected evidence. It prevents the future adapter from proving only the happy path.

Non-Authority Notice

This matrix does not authorize Runtime behavior, WebUI Product behavior, Case execution, real-repo mutation, merge, deploy, push, close, vendor-source mutation, external developer repository mutation, or Core promotion.

Matrix Rules

• Each row maps to the CTO Harness Evidence Interface.
• Each row must produce report.json, events.normalized.jsonl, patch.diff, test.log, and trace.jsonl when implemented.
• Each row must produce artifact_digests and freshness proof when implemented.
• Each row must record a blocker reason in report.json.
• Each row must emit a normalized event when the failure class has one.
• Each row must fail closed with status set to fail or blocked.
• Each row must use nonzero exit behavior when the adapter contract marks the failure executable.
• This matrix is planning-only and does not run Case.

Required Failure Fixtures

Fixture	Trigger	Expected blocker reason	Normalized event	Report status	Exit behavior	Evidence mapping
no-diff	Backend reports success but no source diff exists when a diff is required.	no_diff	git.diff.checked	fail	nonzero	patch.diff exists and is empty; changed_files is empty; blockers includes no_diff.
disallowed-file	Backend changes a path outside allowed_paths.	disallowed_file_change	git.diff.checked	fail	nonzero	changed_files lists offending path; allowed_writes_passed is false; patch.diff captures the change.
failed-tests	Verification command exits nonzero.	verification_failed	verification.completed	fail	nonzero	test.log captures failing command output; verification records command and nonzero exit.
missing-test-command	Task contract requires verification but no command is available.	missing_test_command	verification.completed	blocked	nonzero	test.log states no command was available; verification records missing command.
missing-event	Required normalized event is absent or out of order.	missing_required_event	run.completed	fail	nonzero	events.normalized.jsonl is present; validator identifies missing or out-of-order event.
reviewer-reject	Case reviewer rejects the result.	reviewer_rejected	verification.completed	blocked	nonzero	backend raw logs record reviewer rejection; normalized evidence records blocked result without approving mutation.
approval-denied	Human approval is required and denied.	approval_denied	approval.denied	blocked	nonzero	approval event records actor, scope, mutation mode, timestamp, and denial.
timeout	Backend or verification exceeds configured timeout.	timeout	run.completed	blocked	nonzero	trace.jsonl records timeout point; report.json records timeout blocker.
dirty-starting-tree	Target repository is dirty before backend work starts when clean start is required.	dirty_starting_tree	task.contract.created	blocked	nonzero	trace.jsonl records preflight failure; no mutation occurs.
dirty-ending-tree	Run leaves untracked or unintended dirty state after checks.	dirty_ending_tree	run.completed	fail	nonzero	trace.jsonl records ending state check; report.json names dirty paths.
artifact-write-failure	Required artifact cannot be written.	artifact_write_failure	run.completed	fail	nonzero	report.json may be partial only if write failure happens after report creation; trace records failed artifact path.
provider-unavailable	Backend provider, model, CLI, or dependency is unavailable.	provider_unavailable	run.completed	blocked	nonzero	backend raw logs record provider failure; no source mutation occurs.

Acceptance Rule

A future Case adapter cannot progress to staged proof until these fixture classes have expected evidence defined in the adapter validator.

The first executable implementation may start with a subset only if the staged proof gate explicitly marks the remaining rows as blocked and not accepted for default candidacy.

Validator Expectations

Current validation is planning-only and checks this matrix exists with required rows.

Later adapter validation must execute or simulate each row and verify:

• blocker reason;
• normalized event;
• report status;
• exit behavior;
• required artifact presence;
• digest presence;
• freshness proof;
• no hidden source mutation.