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Evidenceramda-2391

Discrepancy between propOr and pathOr

ramda#2391, at commit 4e3c65d. A closed issue from a repository Credda did not choose.

LIVE2026-09-20

RIGHT_FAILURE

executed against the upstream checkout.

Outcome
PATCH_REJECTED
Wall time
554.0s
Checks
5 passed of 5 applicable

RECORDED

NOT_GRADED

graded from the transcript committed with this case.

Outcome
not recorded
Checks
none run
Repository
ramda/ramda
Issue
#2391
Pinned commit
4e3c65dbd05bf77061db112358ced5d3b4962ad2

01The signal

The report, exactly as it was filed.

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

ramda#2391 · as filedcommit 4e3c65d

Discrepancy between propOr and pathOr

See REPL link here: https://goo.gl/7UGda4

It seems to me that `propOr` and `pathOr` behave differently.

```
const getProp1 = R.propOr([], 'x');
const getProp2 = R.pathOr([], ['x']);

getProp1({x: null});    // returns null
getProp2({x: null});    // returns []
```

Without checking the code, I'm guessing `propOr` uses `has` internally, whereas `pathOr` is just checking for a falsey result.

Is this expected, or is this a bug?
Repository
ramda/ramda
Issue
#2391
Commit
4e3c65dbd05bf77061db112358ced5d3b4962ad2
Why this commit
The first parent of the fix commit e26fe5bd606855e9c52d291dc9ce6a56ccfbf461, which GitHub binds to this issue via CLOSED_EVENT_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
(R.propOr([], 'x'))({x: null}) produces null; the fix makes it produce [].
Expression
(R.propOr([], 'x'))({x: null})
Reported output
null
Where that came from
Read mechanically from the report's fenced code, SAME_LINE form: `getProp1({x: null}); // 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
`getProp1({x: null})` 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.

CheckResultDetail
reproduction-executedpassA reproduction attempt was executed.
signature-capturedpass`getProp1({x: null})` still produces null (read null)
right-failurepassReproduced the reported failure: (R.propOr([], 'x'))({x: null}) produces null; the fix makes it produce [].
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 4e3c65d, 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/ramda/ramda
git checkout 4e3c65dbd05bf77061db112358ced5d3b4962ad2
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