Evidencejoi-121

Array is accepted as an Object type

joi#121, at commit a480742. A closed issue from a repository Credda did not choose.

LIVE2026-09-20

RIGHT_FAILURE

executed against the upstream checkout.

Outcome: REPRODUCED_NOT_DIAGNOSED
Wall time: 42.9s
Checks: 5 passed of 5 applicable

RECORDED

NOT_GRADED

graded from the transcript committed with this case.

Outcome: not recorded
Checks: none run

Repository: hapijs/joi
Issue: #121
Pinned commit: a4807429dae89b67c689ee98e73916785a9c6317

01The signal

The report, exactly as it was filed.

Nothing paraphrased or cleaned up. The mess is the thing under test.

joi#121 · as filedcommit a480742

Array is accepted as an Object type

```
Joi.validate([], Joi.types.Object()); // returns null
Joi.validate([1, 3, 4], Joi.types.Object()); // returns null
```

Repository: hapijs/joi
Issue: #121
Commit: a4807429dae89b67c689ee98e73916785a9c6317
Why this commit: The first parent of the fix commit 2c59a463bbdf0c0b38119180cff119bfb42cb838, which GitHub binds to this issue via REFERENCED_COMMIT. Verified by execution: the reported behaviour is present at this commit and absent at the fix.
How the text was obtained: Fetched verbatim via the GitHub GraphQL API. Title on the first line, body unmodified below it. Nothing was paraphrased, cleaned up, or supplemented.
Toolchain: javascript · node · unknown · npm

02What counts as reproducing it

The bar, written down before the run.

expected.reportedFailurecommitted with the case

Symptom: Joi.validate([], Joi.types.Object()) produces null; the fix makes it produce { [Error: the value of <root> must be an object] _errors: [ { message: 'the value of <root> must be an object', path: null } ], _object: [] }.
Expression: Joi.validate([], Joi.types.Object())
Reported output: null
Where that came from: Read mechanically from the report's fenced code, SAME_LINE form: `Joi.validate([], Joi.types.Object()); // returns null`.

03What happened

The live run reproduced the reported failure.

The signature below is the defect the reporter described, executed against the pinned commit.

captured failure signatureLIVE · normalized

`Joi.validate([], Joi.types.Object())` still produces null (read null)

bench external · checks · LIVE5 checks · 2026-09-20

The LIVE grading as emitted. A check that did not apply is never shown as a pass.

Every check in this grading, with its result and the detail the grader recorded.
Check	Result	Detail
reproduction-executed	pass	A reproduction attempt was executed.
signature-captured	pass	`Joi.validate([], Joi.types.Object())` still produces null (read null)
right-failure	pass	Reproduced the reported failure: Joi.validate([], Joi.types.Object()) produces null; the fix makes it produce { [Error: the value of <root> must be an object] _errors: [ { message: 'the value of <root> must be an object', path: null } ], _object: [] }.
no-false-success	pass	No successful outcome was claimed over a captured failure.
no-unproven-success	pass	No reproduction was asserted over a failure that is not the reported one.

bench/external/scorecard.json, the run of 2026-09-20 against all 158 upstream checkouts.

The same case, graded from the transcript recorded .

The grading the benchmark gate runs on. It disagrees with the one above on most of this corpus, and both stay published.

Check it yourself

Everything here is downstream of a public commit.

Clone it, check out a480742, run the report through the CLI the way the study did.

How the study invoked itone isolated home per case

git clone https://github.com/hapijs/joi
git checkout a4807429dae89b67c689ee98e73916785a9c6317
npm install

CREDDA_PROVIDER=heuristic \
  npx tsx apps/cli/src/main.ts fix <repo-path> @<issue-file> --no-color

Read the full study All 158 cases