Evidenceluxon-1058

Parsing fractional hours durations

luxon#1058, at commit f4e0605. 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: 73.5s
Checks: 5 passed of 5 applicable

RECORDED

NOT_GRADED

graded from the transcript committed with this case.

Outcome: not recorded
Checks: none run

Repository: moment/luxon
Issue: #1058
Pinned commit: f4e06053b27e0737be50d9569feb86cf91d5fb80

01The signal

The report, exactly as it was filed.

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

luxon#1058 · as filedcommit f4e0605

Parsing fractional hours durations

**Describe the bug**
I've discovered this problem when trying to parse back ISO duration acquired from Luxon previously. Many of my durations ended up being empty objects. After some further investigation, it appears to be a problem in parsing fractional hours durations.


**To Reproduce**

I've made following test case to prove this problem: 478abdc82319336b5ab1b6b385927e5bde423eb4

You can also test this problem in my RunKit: https://runkit.com/spodjasek/luxon-fractional-hours

**Actual vs Expected behavior**

After running:
```javascript
Duration.fromISO('PT9.5H').toObject()
```

I expect returned object to be:
```javascript
{hours: 9.5}
```

Instead of above I receive empty object:
```
{}
```

**Desktop (please complete the following information):**

- OS: Linux
- Run on Node
- Luxon version 2.0.2
- Timezone `Europe/Warsaw`, but also tested in `America/New_York`

Repository: moment/luxon
Issue: #1058
Commit: f4e06053b27e0737be50d9569feb86cf91d5fb80
Why this commit: The first parent of the fix commit e5a66144b2986237e77206520eac5c4b8319663d, which GitHub binds to this issue via CLOSED_EVENT_PR. 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: Duration.fromISO('PT9.5H').toObject() produces {}; the fix makes it produce { hours: 9.5 }.
Expression: Duration.fromISO('PT9.5H').toObject()
Reported output: {}
Where that came from: Proposed by a model reading this report and nothing else -- it never saw the repository or the fix commit -- and read back as a claim by the same parser the harvest uses, SAME_LINE form: `Duration.fromISO('PT9.5H').toObject() //=> {}`. The report sat in the CODE_NO_ANNOTATION_AT_ALL bucket, which no regex reaches. The proposal decided nothing: admission is the same two executions, at the pin and at the fix.

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

`Duration.fromISO('PT9.5H').toObject()` still produces {} (read {})

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	`Duration.fromISO('PT9.5H').toObject()` still produces {} (read {})
right-failure	pass	Reproduced the reported failure: Duration.fromISO('PT9.5H').toObject() produces {}; the fix makes it produce { hours: 9.5 }.
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 f4e0605, 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/moment/luxon
git checkout f4e06053b27e0737be50d9569feb86cf91d5fb80
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