## The basics
- [x] I [validated my changes](https://developers.google.com/blockly/guides/contribute/core#making_and_verifying_a_change)
## The details
### Resolves
Fixes#8952Fixes#8950Fixes#8971
Fixes a bunch of other keyboard + mouse synchronization issues found during the testing discussed in https://github.com/google/blockly-keyboard-experimentation/pull/482#issuecomment-2846341307.
### Proposed Changes
This introduces a number of changes to:
- Ensure that gestures which change selection state also change focus.
- Ensure that ephemeral focus is more robust against certain classes of failures.
### Reason for Changes
There are some ephemeral focus issues that can come up with certain actions (like clicking or dragging) don't properly change focus. Beyond that, some users will likely mix clicking and keyboard navigation, so it's essential that focus and selection state stay in sync when switching between these two types of navigation modalities.
Other changes:
- Drop-down div was actually incorrectly releasing ephemeral focus before animated closes finish which could reset focus afterwards, breaking focus state.
- Both drop-down and widget divs have been updated to only return focus _after_ marking the workspace as focused since the last focused node should always be the thing returned.
- In a number of gesture cases selection has been removed. This is due to `BlockSvg` self-managing its selection state based on focus, so focusing is sufficient. I've also centralized some of the focusing calls (such as putting one in `bringBlockToFront` to ensure focusing happens after potential DOM changes).
- Similarly, `BlockSvg`'s own `bringToFront` has been updated to automatically restore focus after the operation completes. Since `bringToFront` can always result in focus loss, this provides robustness to ensure focus is restored.
- Block pasting now ensures that focus is properly set, however a delay is needed due to additional rendering changes that need to complete (I didn't dig deeply into the _why_ of this).
- Dragging has been updated to always focus the moved block if it's not in the process of being deleted.
- There was some selection resetting logic removed from gesture's `doWorkspaceClick` function. As far as I can tell, this won't be needed anymore since blocks self-regulate their selection state now.
- `FocusManager` has a new extra check for ephemeral focus to catch a specific class of failure where the browser takes away focus immediately after it's returned. This can happen if there are delay timing situations (like animations) which result in a focused node being deleted (which then results in the document body receiving focus). The robustness check is possibly not needed, but it help discover the animation issue with drop-down div and shows some promise for helping to fix the variables-closing-flyout problem.
Some caveats:
- Some undo/redo steps can still result in focus being lost. This may introduce some regressions for selection state, and definitely introduces some annoyances with keyboard navigation. More work will be needed to understand how to better redirect focus (and to what) in cases when blocks disappear.
- There are many other places where focus is being forced or selection state being overwritten that could, in theory, cause issues with focus state. These may need to be fixed in the future.
- There's a lot of redundancy with `focusNode` being called more than it needs to be. `FocusManager` does avoid calling `focus()` more than once for the same node, but it's possible for focus state to switch between multiple nodes or elements even for a single gesture (for example, due to bringing the block to the front causing a DOM refresh). While the eventual consistency nature of the manager means this isn't a real problem, it may cause problems with screen reader output in the future and warrant another pass at reducing `focusNode` calls (particularly for gestures and the click event pipeline).
### Test Coverage
This PR is largely relying on existing tests for regression verification, though no new tests have been added for the specific regression cases.
#8910 is tracking improving `FocusManager` tests which could include some cases for the new ephemeral focus improvements.
#8915 is tracking general accessibility testing which could include adding tests for these specific regression cases.
### Documentation
No new documentation is expected to be needed here.
### Additional Information
These changes originate from both #8875 and from a branch @rachel-fenichel created to investigate some of the failures this PR addresses. These changes have also been verified against both Core's playground and the keyboard navigation plugin's test environment.
* test(BlockSvg): Add tests for setParent(null) when dragging
Add tests for scenarios where block(s) unrelated to the block
being disconnected has/have been marked as as being dragged.
Due to a bug in BlockSvg.prototype.setParent, one of these
fails in the case that the dragging block is not a top
block.
Also add a check to assertNonParentAndOrphan to check that the
orphan block's SVG root's parent is the workspace's canvass
(i.e., that orphan is a top-level block in the DOM too).
* fix(BlockSvg): Fix bug in setParent re: dragging block
Fix an incorrect assumption in setParent: the topmost block
whose root SVG element has the blocklyDragging class may not
actually be a top-level block.
* refactor(BlockDragStrategy): Hide connection preview earlier
* chore(BlockDragStrategy): prefer ?. to !.
Per nit on PR #8934.
* fix(BlockSvg): Spelling: "canvass" -> "canvas"
* feat: Add methods for toggling and inspecting the readonly state of a workspace.
* refactor: Use the new readonly setters/getters in place of checking the injection options.
* fix: Fix bug that allowed dragging blocks from a flyout onto a readonly workspace.
* feat: Toggle a `blocklyReadOnly` class when readonly status is changed.
* chore: Placate the linter.
* chore: Placate the compiler.
* refactor(events): Use "export ... from" where applicable
* refactor(events): Introduce EventType enum
Introduce an enum for the event .type values. We can't actually
use it as the type of the .type property on Abstract events,
because we want to allow developers to add their own custom
event types inheriting from this type, but at least this way we
can be reasonably sure that all of our own event subclasses have
distinct .type values—plus consistent use of enum syntax
(EventType.TYPE_NAME) is probably good for readability overall.
Put it in a separate module from the rest of events/utils.ts
because it would be helpful if event utils could use
event instanceof SomeEventType
for type narrowing but but at the moment most events are in
modules that depend on events/utils.ts for their .type
constant, and although circular ESM dependencies should work
in principle there are various restrictions and this
particular circularity causes issues at the moment.
A few of the event classes also depend on utils.ts for fire()
or other functions, which will be harder to deal with, but at
least this commit is win in terms of reducing the complexity
of our dependencies, making most of the Abstract event subclass
module dependent on type.ts, which has no imports, rather than
on utils.ts which has multiple imports.
* chore(deps): Add pretter-plugin-organize-imports
* chore: Remove insignificant blank lines in import sections
Since prettier-plugin-organize-imports sorts imports within
sections separated by blank lines, but preserves the section
divisions, remove any blank lines that are not dividing imports
into meaningful sections.
Do not remove blank lines separating side-effect-only imports
from main imports.
* chore: Remove unneded eslint-disable directives
* chore: Organise imports
Add a condition check so that we don't unset
the group ID that is not set by us. Otherwise the
multi-select plugin undo/redo will be broken (apply
individually instead of all together)
Signed-off-by: Hollow Man <hollowman@opensuse.org>
* fix: delete area animation
* chore: format
* Update core/dragging/dragger.ts
Co-authored-by: Christopher Allen <cpcallen+github@gmail.com>
---------
Co-authored-by: Christopher Allen <cpcallen+github@gmail.com>
* feat: have block use drag strategy
* fix: gesture to use dragger for blocks
* chore: register dragger
* chore: remove getInsertionMarkers and pull logic into workspace
