Bug 7107 – Refactor Date object to provide direct access to milliseconds/offset

• Status: RESOLVED
• Resolution: FIXED
• Component: JavaScriptCore

[Alexey Proskuryakov]

This is needed to convert JavaScript dates to AppleScript ones in WebCore.

[Alexey Proskuryakov]

Created attachment 6294 [details]
proposed patch

While refactoring the code, I had to also make several Windows-specific changes.

Apparently, the Windows _daylight global has a different meaning than seems to have been expected by GetTimezoneOffset implementation. In fact, _daylight is non-zero if the machine is configured to support daylight savings time, not when DST is active. In other words, there are two ways to make _daylight non-zero:
1) Tick "Automatically adjust clock for daylight saving changes" checkbox in Date and Time control panel - _daylight becomes 1 (the actual value is undocumented).
2) give TZ environment variable a value that includes a DST timezone. E.g.:
set TZ=MSK3  -> _daylight=0
set TZ=MSK3MSD  -> _daylight=77 (value depends on the timezone, also undocumented).

[Darin Adler]

Comment on attachment 6294 [details]
proposed patch

+static bool isTime_tSigned()
+{
+    time_t minusOne = (time_t)(-1);
+    return minusOne < 0;
+}

The above function should be marked inline, because if so it will act as a compile-time constant.

If tested thoroughly, looks good, r=me.