Fixup: unselection of items from AJAX data sources with non-string identifiers

[jayaddison]

This pull request includes a

• Bug fix

The following changes were made

• Adds the jquery-mockjax plugin as a vendored integration test dependency.
• Provides integration test coverage for selection-then-unselection of items based on an AJAX data source.
• Performs normalization of result items received from AJAX sources.

Resolves #6128.

[kevin-brown]

• Maybe-controversial: removes some special-case handling for multi-select controls

Yeah those are too controversial to roll in here. We intentionally don't have single-select elements issue unselect because that'd always be paired with a select.

[kevin-brown]

I am likely going to spin a new ajax-tests.js module out of this and move this test into it, since we don't currently have good tests around AJAX handling and this would be a solid first test to add. More than likely I would switch this to just be testing the AjaxAdapter itself and create a new test around the weirdness with creating <option>s on select events.

[jayaddison]

Thanks @kevin-brown - how would you like to co-ordinate the creation of that test file? (should I attempt to create it here, or would you prefer to do that separately and move these changes into it?)

[jayaddison]

Yeah those are too controversial to roll in here. We intentionally don't have single-select elements issue unselect because that'd always be paired with a select.

Sounds good; the single-select unselect event change here has been reverted.

[jayaddison]

Also a note: the jquery-mockjax component is available under dual MIT-or-GPLv2 licensing terms (it's up to the authors of the codebase where it is included to decide on the applicable terms). I think I did check the license compatibility before choosing it for this branch, but wanted to double-check that again anyway.

[kevin-brown]

Good call on checking the license, thank you for switching back the unselect changes. This looks good to go from a high level, so I'll mark it for my next sweep.

I'll take care of the testing changes independently, the tests you wrote get the job done for this change set. Anything I add would likely be in addition to the ones here and aren't required.

[jayaddison]

Hey @kevin-brown - I'm afraid I'm joining the chorus of 'any updates on this' here - is there anything I can do to help this and/or the 4.1.0 milestone along?

[jayaddison]

Note, partly since licensing was discussed here previously: jquery-mockjax v2.6.1 has consolidated from dual MIT-and-GPLv2 licensing to a single MIT license (ref: jakerella/jquery-mockjax@8183c94 and the associated changelog entry).