The `getSelectedEditors` function is largely a copy of the `getEditors`
function, with three small differences:
1. `getEditors` allows getting any kind of editor whereas
`getSelectedEditors` is harcoded to only getting selected editors.
2. `getEditors` returns editor selectors (strings) whereas
`getSelectedEditors` returns editor IDs (integers).
3. `getSelectedEditors` returns a sorted array of editor IDs whereas
`getEditors` does not ensure that the array is sorted.
This commit makes the `getEditors` function a drop-in replacement for
the `getSelectedEditors` function to deduplicate the code and to have a
unified way of getting editors.
Note that we don't actually use the contents of the returned array
(only its length), so we can safely change `getEditors` to return a
sorted array of integer editor IDs instead. Sorting the array makes the
return value deterministic, which is a nice property for test stability,
and integer IDs are also easier to handle in test assertions. Note that
the corresponding selector strings can also easily be obtained from the
integer IDs using the `getEditorSelector` function if needed.
It was due the resize observer which is removed thanks to this patch.
In order to reuse the dragAndDrop function in test, this patch slighty refactors it
in order to make it easier to use.
This patch makes a clear separation between the way to draw and the editing stuff.
It adds a class DrawEditor which should be extended in order to create new drawing tools.
As an example, the ink tool has been rewritten in order to use it.
Over time the number of integration tests that get the rectangle for a
given selector has increased quite a bit, and the code to do so has
consequently become duplicated.
This commit refactors the integration tests to move the rectangle
fetching code to a single place, which reduces the code by over 400
lines and makes the individual tests simpler.
The original bug was because the parent was null when trying to show
an highlight annotation which led to an exception.
That led me to think about having some null/non-null parent when removing
an editor: it's a mess especially if a destroyed parent is still attached
to an editor. Consequently, this patch always sets the parent to null when
deleting the editor.
