865627 - Change exists method for handling Lookup expression that does not exist

Status: RESOLVED DUPLICATE of bug 860659

(Testing Graveyard :: Mozmill, defect)

Description

[Daniela Petrovici]

After investigating bug 864375, we have found out that exists method in mozelement does not handle the case where the lookup expression does not exist and an exception is thrown from elementslib.Lookup.

In Mozmill 1.5.21 we had this method: https://github.com/mozilla/mozmill/blob/hotfix-1.5/mozmill/mozmill/extension/resource/modules/elementslib.js#L417 that handled an element that did not exist.

In Mozmill 2.0 when trying to get the element https://github.com/mozilla/mozmill/blob/master/mozmill/mozmill/extension/resource/driver/mozelement.js#L126 (this.element from __defineGetter__ method) we are calling again elementslib.Lookup which will cause an exception since the element does not exist on the page.

Comment 1

[Daniela Petrovici]

Attachment: patch v1.0

Modified exists in mozelement.js returns true if the this.element exists or false in case the element does not exist or an error is thrown when searching for the element.

Comment 2

[Henrik Skupin [:whimboo][⌚️UTC+1]]

Comment on attachment 741794 [details] [diff] [review]
patch v1.0

Review of attachment 741794 [details] [diff] [review]:
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Before we review this please make sure to add a proper test for this particular case.

Comment 3

[Henrik Skupin [:whimboo][⌚️UTC+1]]

I wanna see a testcase here given that I can't see how an exception can be raised by the element getter.

Comment 4

[Henrik Skupin [:whimboo][⌚️UTC+1]]

Attachment: testcase

Comment 5

[Henrik Skupin [:whimboo][⌚️UTC+1]]

So this is not something we should wallpaper in mozelement.js. The real problem lays in elementslib.js and has to be fixed in that file.

Comment 6

[Henrik Skupin [:whimboo][⌚️UTC+1]]

This is actually a dupe of bug 860659.