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Evidenceyargs-parser-261

`--option=--value` is wrongly parsed when `option` is an array or has `narg` set

yargs-parser#261, at commit b96b989. A closed issue from a repository Credda did not choose.

LIVE2026-09-20

WRONG_FAILURE

executed against the upstream checkout.

Outcome
INCONCLUSIVE
Wall time
56.0s
Checks
4 passed of 5 applicable

RECORDED

NOT_GRADED

graded from the transcript committed with this case.

Outcome
not recorded
Checks
none run
Repository
yargs/yargs-parser
Issue
#261
Pinned commit
b96b989680be8259ed530876c1e6cb69608e19ef

01The signal

The report, exactly as it was filed.

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

yargs-parser#261 · as filedcommit b96b989

`--option=--value` is wrongly parsed when `option` is an array or has `narg` set

```js
const parse = require('yargs-parser')
console.log(parse('--option=--value'))
```
returns, as expected:
```js
{ _: [], option: '--value' }
```
However:
```js
const parse = require('yargs-parser')
console.log(parse('--option=--value', {
  array: ['option']
}))
```
returns:
```js
{ _: [], option: [], value: true }
```
when it would be expected to return:
```js
{ _: [], option: [ '--value' ] }
```
Same issue with `narg: { option: 1 }`.

`nargs-eats-options` does not change anything to this behavior.
Issue
#261
Commit
b96b989680be8259ed530876c1e6cb69608e19ef
Why this commit
The first parent of the fix commit 41d3f8139e116706b28de9b0de3433feb08d2f13, 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
parse('--option=--value', { array: ['option'] }) does not produce { _: [], option: [ '--value' ] }; the fix makes it do so.
Expression
parse('--option=--value', { array: ['option'] })
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: `parse('--option=--value', { array: ['option'] }) //=> { _: [], option: [ '--value' ] }`. 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

A real failure was captured. It was the wrong one.

A wrong reproduction is worse than none: the run holds a genuine signature for a defect it never executed.

captured failure signatureLIVE · normalized
`parse('--option=--value')` still produces { _: [], option: '--value' } (read { _: [], option: '--value' })
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.

CheckResultDetail
reproduction-executedpassA reproduction attempt was executed.
signature-capturedpass`parse('--option=--value')` still produces { _: [], option: '--value' } (read { _: [], option: '--value' })
right-failurefailExpected `parse('--option=--value', { array: ['option'] })` not producing { _: [], option: [ '--value' ] }.
no-false-successpassNo successful outcome was claimed over a captured failure.
no-unproven-successpassNo 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 b96b989, 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/yargs/yargs-parser
git checkout b96b989680be8259ed530876c1e6cb69608e19ef
npm install

CREDDA_PROVIDER=heuristic \
  npx tsx apps/cli/src/main.ts fix <repo-path> @<issue-file> --no-color
Read the full studyAll 158 cases