Open Radar

 
29-Jan-2013 04:04 PM Brian Webster:
Summary:
When using Applescript to set the date of a photo in the iPhoto library, if the date is on a day when daylight savings time is either beginning or ending, the date is incorrectly adjusted by an hour.

Steps to Reproduce:
Copy and paste the following Applescript into AppleScript Editor and click "Run":

set aDate to date "Saturday, January 1, 2000 4:24:05 PM"
repeat until aDate > date "Sunday, January 1, 2012 4:24:05 PM"
	tell application "iPhoto"
		set date of first photo to aDate
		set newDate to date of first photo
		if not aDate = newDate then
			display dialog "Date mismatch: " & aDate & " vs " & newDate
		end if
	end tell
	set day of aDate to (1 + (day of aDate))
end repeat

Expected Results:
Setting the photo's date then immediately retrieving it again should always result in the two values being equal, with the "display dialog" command never being hit.

Actual Results:
On certain days, the values do not match, and a message is displayed in a dialog via the script. When I run the script, I get mismatches on:

April 2, 2000
October 29, 2000
April 1, 2001
October 28, 2001
April 7, 2002
October 27, 2002
...
March 11, 2007
November 4, 2007
March 9, 2008
November 2, 2008
... and so on

On the dates in the spring, the times are behind by an hour, and in the fall they are ahead by an hour.

Regression:
Note that the days are definitely the switch days, since they change from April/October to March/November in 2007, when congress passed legislation to lengthen daylight savings time.

Notes: