Date constructor should allow arguments to overflow/underflow

[DartBot]

This issue was originally filed by @seaneagan

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In JavaScript, the Date constructor allows the individual parts to overflow and underflow. This facilitates calendar based date addition and subtraction, and other relative date manipulation, for example:

final now = new Date.now();

// "end of" dates
final endOfDay = new Date(now.year, now.month, now.day + 1, 0, 0, 0, 0);
final endOfMonth = new Date(now.year, now.month + 1, 0, 0, 0, 0);

// date addition, including DST transitions
final inNinetyDays = new Date(now.year, now.month, now.day + 90, now.hours, now.minutes, now.seconds, now.milliseconds);
final sixMonthsAgo = new Date(now.year, now.month - 6, now.day, now.hours, now.minutes, now.seconds, now.milliseconds);

The dart2js version of Date supports this, since it just compiles to using the native JavaScript Date constructor. The VM version though currently does not allow this, it adds checks that each part is within bounds (1 - 12 for month, 1 - 31 for day, 0 - 23 for hour, 0 - 59 for minute and second, 0 - 999 for millisecond).

[DartBot]

This comment was originally written by @seaneagan

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Go lang agrees:

http://golang.org/pkg/time/#Date

[dgrove]

Added Area-VM, Triaged labels.

[ghost]

Set owner to @floitschG.
Removed Area-VM label.
Added Area-Library label.

[floitschG]

Issue #1154 has been merged into this issue.

[floitschG]

Issue #445 has been merged into this issue.

[DartBot]

This comment was originally written by domi...@google.com

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Set owner to domi...@google.com.
Added Started label.

[DartBot]

This comment was originally written by dominich@chromium.org

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https://chromiumcodereview.appspot.com/10832166

[DartBot]

This comment was originally written by domi...@google.com

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Added Fixed label.