atomic-design-poc/docs/project/archive/refactor-backlog-setup/refactor-backlog/implementation/rb-33.md

RB-33 — unwrapOk: adopt or delete

Status: implemented · 2026-08-28 · Source finding: 06-adr-conformance.md ADR-C-011 · 99-backlog.md RB-33

Decision: delete

The ticket names this "adopt or delete", not "adopt", and asks for the judgment call, not the default. I deleted unwrapOk.

Why delete, not adopt

unwrapOk (libs/shared/src/testing/value-object.ts) has had zero consumers across the whole codebase since ADR-0006 shipped it, except its own definition and one sentence in libs/shared/docs/testing.mdx. I verified this before changing anything:

grep -rn "unwrapOk" apps libs --include=*.ts --include=*.mdx
libs/shared/docs/testing.mdx:92:  ...unwrapOk(parseX(raw))...
libs/shared/src/testing/value-object.ts:9:export function unwrapOk<E, T>(...)
libs/shared/src/testing/value-object.ts:11:  throw new Error(`unwrapOk: ...`);

The one call site the finding names, apps/ssp/src/app/registratie/application/submit-change-request.spec.ts, still has the exact hand-rolled guard the finding quotes:

const telefoon = parseTelefoonnummer('0612345678');
if (!telefoon.ok) throw new Error('fixture phone should parse');

I also checked whether any other spec has the same shape, in case the finding's "one call site" undercounted the real duplication:

grep -rln "if (!.*\.ok)\s*throw" apps libs --include=*.spec.ts
apps/ssp/src/app/registratie/application/submit-change-request.spec.ts

Only this one file, anywhere. There is no cast ('x' as Telefoonnummer) to close off either — the spec already calls the real parseTelefoonnummer and checks .ok before touching .value. ADR-0006 §3's actual requirement ("never a cast") is already met by the inline code, with or without the helper.

Weighing it honestly:

• For adopt: it is a one-line change, and the ADR's own worked example literally shows this exact call. Doing it would make the finding's "zero adopters" claim technically false.
• For delete: a helper that gains its only real-codebase consumer by an agent adding that one call site as an act of ticket compliance is not organic adoption — it is manufacturing a usage to justify keeping the file. unwrapOk has sat available, exported, and documented since ADR-0006 (well before this session) without a single spec reaching for it on its own. One caller, forever, is not "removing duplication" (the stated point of a shared test helper) — there is no duplication with only one occurrence. The inline guard is also arguably clearer here: its error message ('fixture phone should parse') names the actual fixture, where unwrapOk's generic message (unwrapOk: expected ok, got error: ...) does not.

Delete wins: it removes dead, unadopted code and its stale doc reference, changes no runtime behaviour anywhere, and costs nothing to reverse if a second real need for this idiom shows up later (three lines, trivial to re-add against actual duplication instead of a single hypothetical site).

What changed

File	Change
libs/shared/src/testing/value-object.ts	Deleted. Its only export, unwrapOk, is what this ticket removes; the file had nothing else in it.
libs/shared/docs/testing.mdx	Rewrote the sentence that named unwrapOk and the deleted file's path. It now states the same rule in plain terms — call the real parse* and check .ok, never a cast — and keeps the RemoteData half of the sentence pointing at remote-data.ts (unchanged, still in use).
apps/ssp/src/app/registratie/application/submit-change-request.spec.ts	Not touched. Its inline guard already satisfies ADR-0006 §3; this is the "delete" branch, so the fixture-construction behaviour stays exactly as it was.
99-backlog.md	RB-33's status cell: open → implemented.

What this ticket did not touch

docs/reference/architecture/0006-test-data-builders.md (the ADR itself) still shows unwrapOk in its worked example and decision table. That is deliberate: RB-33 is a code ticket, not one of the five ADR-fix tickets that need architect sign-off (06-adr-conformance.md's "ADR-fix tickets" section). The ADR's illustrated pattern ("call the real parser, unwrap through a checked path, never a cast") is still the correct principle — this ticket only removes one now-unused concrete implementation of it, which the inline guard in submit-change-request.spec.ts already satisfies without the named helper. Amending the ADR's own text is out of this ticket's scope and is left for a future ADR-fix ticket if one is ever raised. The finding document (06-adr-conformance.md) and the historical WP-70/WP-71 backlog notes that mention unwrapOk are left as-is — they are records of what was true when written, not living code.

No other file in libs/shared/src/testing/ was touched (expect-tag.ts, machine.ts, remote-data.ts are all unrelated and still have real consumers).

Verification

• grep -rn "unwrapOk" apps libs --include=*.ts --include=*.mdx — zero occurrences.
• apps/ssp/src/app/registratie/application/submit-change-request.spec.ts — unchanged file, still passes (see npm run ci result below).
• No new test added. The ticket is a deletion of unused code plus a doc-sentence rewrite; the surviving inline guard in the spec is exercised the same way it always was, by the spec's three existing it blocks.
• npm run ci (foreground): see the session report for the exit code and step count.