i/6536: Implemented the select all feature

[oleq]

Feature: Implemented the select all feature. Closes ckeditor/ckeditor5#6536.

---

To be merged together with:

• A PR in ckeditor5-essentials making this an essential editor feature.
• A PR in ckeditor5-widget in which I removed the Ctrl+A handling added by the Widget plugin. SelectAll takes care of widgets now.
• A PR in ckeditor5-theme-lark adding the select all icon to the manual test.
• A branch in ckeditor5.

---

Q: Do we need a feature guide? That would be a very short one but maybe it's worth adding. cc @Reinmar

---

FYI: The feature brings a UI button, which looks as follows:

[jodator]

Basically I see room for improvement in tests. Maybe it is worth testing it with table > image also?

I'm confused with the keystrokes vs listenTo( viewDocument ) usage as I don't see difference in them and personally I would use editor.keystrokes. So this is question to @Reinmar alongside @oleq ones.

ps.: besides that LGTM 👍 for merging.

[jodator]

I think that we are safe but WDYT about adding a table test?

This would be a scenario for nested-nested editable.

[oleq]

Nested editable is tested in the image caption.

[jodator]

Yes, but a nested editable in a nested editable case - to be sure that we select inner, not the outer nested editable.

[oleq]

Alright, makes sense 👍

[oleq]

Ready for another round of review.

[oleq]

An afterthought: do you think it would be a nice UX if pressing Ctrl+A in a nested editable which content is already selected (double Ctrl+A) selected the closest limit ancestor?

For instance, root->table->cell->image width caption. Double Ctrl+A in the caption would select the entire content of a cell. And a double Ctrl+A would select the entire root.

[Reinmar]

Q: Do we need a feature guide? That would be a very short one but maybe it's worth adding. cc @Reinmar

👍  because of the "select all"  button. Otherwise, it will be extremely hard to find.

[Reinmar]

An afterthought: do you think it would be a nice UX if pressing Ctrl+A in a nested editable which content is already selected (double Ctrl+A) selected the closest limit ancestor?

Just to make sure that I understand correctly. In the following case:

For instance, root->table->cell->image->caption

1. Ctrl+A to select image caption
2. Ctrl+A to select the image
3. Ctrl+A to select the cell content (if the image is not already its only content)
4. Ctrl+A to select the entire table
5. Ctrl+A to select the entire root?

Sounds great.

[oleq]

Honestly, I’d skip 2 and 4. They don’t feel like select all but widget features.

[Reinmar]

BTW, the way to implement that behaviour of selecting the next "thing" on Ctrl+A press when entire content of a limit element is selected is to look for the next object element. That'll be more semantically correct than looking for another limit element.

All objects are by default limit elements, so looking for another limit would work fine. But conceptually we're looking then for another object.

See #1 (comment).

[Reinmar]

Honestly, I’d skip 2 and 4. They don’t feel like select all but widget features.

Could be this way too 👍

This would also invalidate my previous comment.

[oleq]

👍  because of the "select all"  button. Otherwise, it will be extremely hard to find.

Created.

Sounds great.

I created a follow-up: ckeditor/ckeditor5#6621. I think this could be a great intro ticket.

---

Ready for another round of review :)