## Summary
Fixes#22475
`cookie.isExpired()` was incorrectly returning `false` for cookies with
`Expires` set to Unix epoch (Thu, 01 Jan 1970 00:00:00 GMT).
## The Problem
The bug had two parts:
1. **In `Cookie::isExpired()`**: The condition `m_expires < 1`
incorrectly treated Unix epoch (0) as a session cookie instead of an
expired cookie.
2. **In `Cookie::parse()`**: When parsing date strings that evaluate to
0 (Unix epoch), the code used implicit boolean conversion which treated
0 as false, preventing the expires value from being set.
## The Fix
- Removed the `m_expires < 1` check from `isExpired()`, keeping only the
check for `emptyExpiresAtValue` to identify session cookies
- Fixed date parsing to use `std::isfinite()` instead of implicit
boolean conversion, properly handling Unix epoch (0)
## Test Plan
- Added regression test in `test/regression/issue/22475.test.ts`
covering Unix epoch and edge cases
- All existing cookie tests pass (`bun bd test test/js/bun/cookie/`)
- Manually tested the reported issue from #22475
```javascript
const cookies = [
'a=; Expires=Thu, 01 Jan 1970 00:00:00 GMT',
'b=; Expires=Thu, 01 Jan 1970 00:00:01 GMT'
];
for (const _cookie of cookies) {
const cookie = new Bun.Cookie(_cookie);
console.log(cookie.name, cookie.expires, cookie.isExpired());
}
```
Now correctly outputs:
```
a 1970-01-01T00:00:00.000Z true
b 1970-01-01T00:00:01.000Z true
```
🤖 Generated with [Claude Code](https://claude.ai/code)
---------
Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
