Fil opened a new issue, #40718:
URL: https://github.com/apache/arrow/issues/40718
### Describe the bug, including details regarding any error messages,
version, and platform.
Doing a round-trip with a JavaScript Date in apache-arrow/js sometimes
results in wrong values:
```js
import * as Arrow from "apache-arrow";
const date = new Date(1950, 1, 0);
const data = [{date}]
console.warn("true date", date, +date);
const arrow = Arrow.tableFromJSON(data);
const [lo, hi] = arrow.batches[0].data.children[0].values;
console.warn("encoded bytes", hi * (2**32) + lo);
for (const d of arrow) console.log("decoded date", d.date, +d.date)
```
this prints:
```
❯ node test-arrow.js
true date 1950-01-30T23:00:00.000Z -628563600000
encoded bytes -628563600000
decoded date 1950-03-21T16:02:47.296Z -624268632704
```
As you can see there is a difference of 45 days. If I go and modify
factories.ts and change `dtypes.DateMillisecond` to `dtypes.Float64` (line
122), the decoding returns the correct number.
version information:
```
apache-arrow@^15.0.2:
resolved
"https://registry.yarnpkg.com/apache-arrow/-/apache-arrow-15.0.2.tgz#d87c6447d64d6fab34aa70119362680b6617ce63";
❯ node -v
v20.11.1
```
The results are correct for dates after epoch, but testing with `new
Date(1969, 11, 31);` exhibits the problem.
### Component(s)
JavaScript
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