Code optimization for datepicker.js

[saket-joshi]

No description provided.

[wesleycho]

This should not have a merge commit in history.

[wesleycho]

Is this an optimization? I believe that the change should be slower than the original.

[saket-joshi]

• Actually not! Since $scope.datepickerOptions = $scope.datepickerOptions || {} is expression rather than a condition.
• In case $scope.datepickerOptions does not have a value, a blank object would be returned in the same statement. If we use the if.. condition block, the "!" condition would still be checked even if it has a value.

[pkozlowski-opensource]

Guys, this is probably a case of a micro-optimization that can trigger a nice discussion but probably will have negligible impact in practice - unless has numbers that prove things otherwise! So, let's have something that is more readable.

[icfantv]

@saket-joshi, if you would like this to remain open, please produce numbers with associated code that indicates this is a performance improvement. Otherwise, this will be closed. Thanks.

[ghost]

Actually this "micro-optimization" is slower than a condition.
https://jsbench.github.io/#7bdb181e8c7e4fd249726e4b8159d63d When values exists.
https://jsbench.github.io/#0e971943cf0e394f910cfdf1f6918abe When value does not exist.

In Firefox 50.0 $scope.object = $scope.object || {}; is 3 times slower than if (!$scope.object) {$scope.object = {};}
Google Chrome performs better but still the if case is faster.

Maybe my test Setup and Teardown are not correct, but I doubt it.