CI checks doesn't catch commit subject whitespace errors

$ git log --format="%s" | head -n 10
CLN: revisit build warnings in cython templates
 ENH: Raise ValueError for unsupported Window functions (#27275)
BUG: fix inserting tz-aware datetime to Series, closes #12862 (#27322)
CLN: requested follow-ups (#27332)
BUG: Consistent division by zero behavior for Index/Series (#27321)
TST: suppress rolling warnings correctly for raw= (#27330)
CLN: replace usage internally of .iteritems with .items (#26114)
BUG: appending a Timedelta to Series incorrectly casts to integer (#27303)
CLN: Split test_window.py (#27305)
check early for non-scalar default_fill_value (#27302)

$ git log --format="%s" | grep "^ " | wc -l
44

There are multiple recent instances.

[WillAyd]

Is this a common thing to check for?

[jorisvandenbossche]

How would it be checked? If you have multiple commits, the commit message comes from the github PR title. So you would need a github app / bot that checks that.

[jorisvandenbossche]

So where did the leading space come from?

No idea, but if not from the PR title and not from the commit message, then human error when merging is the only thing I can think of. And we will not be able to have a CI check for human error ;)