feat(ngSwitch): Allow multiple case matches for one element

[lrlopez]

Now you can also use an array in ng-switch-when, which allows specifying multiple values for the same element. Values will be evaluated within the scope when using the array notation.

I.e. ng-switch-when="[1, 3, 'hello', 5-3]"

Each element will switch only once even if there are multiple matches in the same element.

BREAKING CHANGE: Previously ng-switch-when expressions that matched against square brackets strings won't work anymore. The fix is encapsulate the string into a one-element array.
I.e. before ng-switch-when='[hi]', now ng-switch-when="['[hi]']"

Closes #3410

[mary-poppins]

Thanks for the PR!

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Thanks again for your help!

[lrlopez]

This PR adds 60 bytes to the minified build.

Edit: Mary Poppins is now happy :)

[L42y]

👍

[petebacondarwin]

Arguably this has a breaking change in the case the someone wanted to match to a string that was wrapped in square brackets.

[lrlopez]

@petebacondarwin Thanks, you're right. I've updated the commit message to address this.

[lgalfaso]

Hi, even when I do see some value in this enhancement, the use of $eval gives a big potential for abusing of this feature. Why not limit this to JSON?

[lrlopez]

The idea behind using $eval is precisely that avoids abusing of interpolation: Instead of doing ng-switch-when="[{{var1}}, {{var2}}, {{var3}}]" you could do just ng-switch-when="[var1, var2, var3]"

Anyway, I could switch to JSON.parse if that is the general consensus.

[lgalfaso]

If there is a general consensus that $eval is better, I am fine with that. Anyhow, doing an $eval has some unexpected side-effects

Say $scope.foo = $q.when('bar');, then $scope.$eval('[foo]'); will be an array with a promise and ['{{foo}}'] will print out ['bar'] that is what most people would expect

[lrlopez]

Either way I think it's a valuable feature. I hope it gets reviewed soon...

[lrlopez]

Could someone from the team tag this PR? Thank you!

[caitp]

@lrlopez backlog more or less means its on our list of things to get to, but it may not be a priority for this release (which is mostly revolving around migrating over to the new doc generator).

But, just to give it some quick review, the issue here is that it sort of says "hey, sometimes this attribute is a plain string, and sometimes it's treated as an angular expression", despite not actually using the expression parser.

I think we could have a better solution which doesn't add any inconsistency by having a separate attribute which is parsed as an expression, instead.

[lrlopez]

Caitlin, thanks for your reply. I found the backlog milestone description just after posting. I agree that a possible solution is having a separate attribute, does everybody agree? The new attribute could be named ng-switch-when-expr or something similar.

[atian25]

any good news for this issue?

[lrlopez]

@atian25, I'm just waiting for someone from the core team to give me the green light about the new attribute...

[rodyhaddad]

Why not use a comma-separated list?
<div ng-switch-when="home, settings">

It's to easy to implement and understand

[Narretz]

#10798 is the way forward, I hope we can get it into 1.5

[vsraptor]

This does not seem to be working in angular 1.5.8 !!!

[gkalpak]

@vsraptor, we went with #10798 which will probably be included in 1.5.10.

[vsraptor]

When is the new version expected to be published

[gkalpak]

It should have been released by the end of next week (probably sooner).