In order to enable the ability to uniquely identify a result by an ID
in the DOM, we generate a new ID for the result based on a combination
of things, including the container ID prefix that is generated and
used elsewhere in Select2. This has worked fairly well for use cases
including attaching Select2 to an existing `<select>` and loading in
options from a remote data set.
Unfortunately, because this process relied on the container ID being
used as a prefix, this failed for options which were automatically
generated on initialization using the `data:` option to Select2.
These were not being generated with an ID because at the time that
they were being generated, the data adapter was not aware of the
container it was being used in. This broke some accessibility features
because we had a mix of options in the results list with IDs, and
some without, so we fixed the ordering to make this work.
Option generation no longer happens when the data adapter is first
initialized, which is where it was previously happening, and instead
it now occurs when the data adapter is bound to the container. This
allows us to ensure that the data adapter is always aware of the
container it is being associated with, so now it will be able to
generate the result IDs.
This also fixes the tests for the array adapter as well as the
legacy `<input />` adapter so they properly bind to a container
during the test. This was causing test failures becuase the options
which would previously be generated during initialization were no
longer appearing.
Fixes#4350
* Update tests to be compatible with jQuery 3.0.0
There was a change in jQuery 3 that ensures that the return value of `.val()` on a multiple select is always an array. This is a breaking change from previous versions, where `null` or `undefined` were returned in these scenarios. Because we cannot `assert.equal` on a list of possible values, these assertions were switched to `assert.ok` which should be good enough.
* Properly strip out units in positioning tests
Before we were assuming that there were no units, and only were we stripping them out if we were expecting 3 digits. Now we just strip out all non-digit characters, so that should do the job and get us what we want.
There was a change in jQuery 3.2.0 that caused the units to be returned in these specific calls. They were not previously being returned, so this was not actually an issue.
* Add automated testing against jQuery 3.4.1
No tests appear to be currently failing.
This adds a broken test that demonstrates the issue seen in
https://github.com/select2/select2/issues/3990 where existing selected
options are being reset once Select2 is initialized. This issue cannot
be reproduced on the options page [1] because the issue only appear to
happen if the selected option is not the first one in the list of
possible options.
[1]: https://select2.github.io/examples.html#data-array
While deep nesting will not work on a standard `<select>`, we can
emulate it through data objects still, and just handle the display
of the data in the results.
This also means that the horrific deep-nested CSS is back to handle
the padding. I hope that will get fixed over time.
This also fixes one of the performance issues with adding array
data, as options are added at the very end instead of one by one.
This converts individual objects passed in through the `array`
parameter to `<option>` tags when Select2 is initialized. This
removes a lot of duplicate code from the `ArrayAdapter`, and keeps
everything closer to the native `<select>` element.
This introduces a breaking change from previous versions of Select2,
where the initial value for array data was blank, even if a blank
option was not present in the original array of objects. Now the
first object passed in will be selected by default, following the
behavior of a standard `<select>` element.
This breaking change does not affect `<select multiple="multiple">`
elements, which by default have no selection.
When using array data, and an option is selected, the data that is
attached to the DOM element will be run through `item` and should
have any private, automatically generated attributes added and
merged with it.
We should only be checking the option values that matter, such as
`id` and `text`, instead of checking all of the option values. This
will prevent unexpected breaking when new properties are added to
the options.
Existing properties should be covered by tests to avoid regressions.
We have to enforce ids being strings as the values of options within
a select will always be an id. This fixes an issue that we had with
array selections not being highlighted in the results.
