undefined | Better HN

0 pointstorstenvl2y ago0 comments

The bug occurs when using setMonth() to a month value containing fewer days than the current date.

There is no limitation in setMonth() such that you can only set the month to "the month after."

I'm sorry, but I think you misunderstand this bug.

0 comments

3 comments · 1 top-level

Izkata2y ago· 2 in thread

I think you did too, I don't have the slightest clue where your math came from. This bug happens when the month you're setting it to has fewer days than the month in the date object, so it rolls the day forward into the next month. It's the same functionality that lets you just add days and iterate over the whole year.

torstenvlOP2y ago

In non-leap years, there are potential invalid target months when the current date is January 29th, January 30th, January 31st, March 29th, March 30th, March 31st, April 29th, April 30th, May 29th, May 30th, May 31st, June 29th, June 30th, July 29th, July 30th, July 31st, August 29th, August 30th, August 31st, September 29th, September 30th, October 29th, October 30th, October 31st, November 29th, November 30th, December 29th, December 30th, or December 31st.

That is, the number of days of a given year where this bug applies are: 3 in January, 3 in March, 2 in April, 3 in May, 2 in June, 3 in July, 3 in August, 2 in September, 3 in October, 2 in November, and 3 in December.

3+3+2+3+2+3+3+2+3+2+3

Izkata2y ago

Where did the 5 come from?

1 more reply

j / k navigate · click thread line to collapse