Evidenceslice-ansi-26

Lose characters when fullwidth characters exist and end is not specified

slice-ansi#26, at commit 9df7d27. A closed issue from a repository Credda did not choose.

LIVE2026-09-20

RIGHT_FAILURE

executed against the upstream checkout.

Outcome: PARTIALLY_VERIFIED
Wall time: 107.8s
Checks: 5 passed of 5 applicable

RECORDED

NOT_GRADED

graded from the transcript committed with this case.

Outcome: not recorded
Checks: none run

Repository: chalk/slice-ansi
Issue: #26
Pinned commit: 9df7d275bbb72b198fbb86818ae277949b16a244

01The signal

The report, exactly as it was filed.

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

slice-ansi#26 · as filedcommit 9df7d27

Lose characters when fullwidth characters exist and end is not specified

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Lose characters when there are fullwidth characters in the string and the third argument `end` is not specified:
```javascript
const str = sliceAnsi("古古test", 0);
// => '古古te'
```


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### Submitted pull Requests
- [#29 supports fullwidth characters & not specified end](https://issuehunt.io/r/chalk/slice-ansi/pull/29)
- [#27 Adjust string length for fullwidth characters when `end` is undefined](https://issuehunt.io/r/chalk/slice-ansi/pull/27)
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Repository: chalk/slice-ansi
Issue: #26
Commit: 9df7d275bbb72b198fbb86818ae277949b16a244
Why this commit: The first parent of the fix commit 013d918970b594d0efd638d0f6fdae6c397ce143, 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: sliceAnsi("古古test", 0) produces '古古te'; the fix makes it produce '古古test'.
Expression: sliceAnsi("古古test", 0)
Reported output: '古古te'
Where that came from: Read mechanically from the report's fenced code, NEXT_LINE form: `const str = sliceAnsi("古古test", 0); // => '古古te'`.

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

`sliceAnsi("古古test", 0)` still produces '古古te' (read 古古te)

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	`sliceAnsi("古古test", 0)` still produces '古古te' (read 古古te)
right-failure	pass	Reproduced the reported failure: sliceAnsi("古古test", 0) produces '古古te'; the fix makes it produce '古古test'.
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 9df7d27, 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/chalk/slice-ansi
git checkout 9df7d275bbb72b198fbb86818ae277949b16a244
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