docs(ngModel): getterSetter and arguments.length vs. angular.isDefined

[yankee42]

When using ng-model-options="{ getterSetter: true }" one should be aware that the getter/setter method could be called with an argument set to undefined even if the method is used as setter. This e.g. happens when the model is invalid:

angular.js/src/ng/directive/ngModel.js

Line 535 in dd8b157

ctrl.$modelValue = allValid ? modelValue : undefined;

Using arguments.length reliably detects whether the getter/setter should act as getter or setter.
Credits for the concept:
#11361 (comment)

I believe that this should be documented as failing to realise this can cause weird behaviour and large time spendings on hunting bugs (at least that happened to me).

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[yankee42]

I signed and also added my github username. I suppose I do not need to set the username AND the email address?!

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[icorne]

I just ran into this issue, Should this not be on master as well?

[gkalpak]

Not sure what you mean. This is a docs change and it has been merged into master as well.

[icorne]

I'm not sure either, yesterday I still saw it with the angular.isDefined , today, it's changed to this version. Maybe my mind is playing tricks on me. Sorry for the disturbance!

[gkalpak]

Np 😃 You were probably viewing the docs of an older version the other day (there is version picker in the top-left).