feat: Add relevant things to full-block field labels

[mikeharv]

The basics

• I validated my changes

The details

Resolves

Fixes #9864

Proposed Changes

This updates how ARIA labels are computed for field classes that support full-block fields (FieldInput and FieldDropdown). When recomputeAriaContext() is called for these fields, we were update the aria-label using the full block's label, which includes a lot of additional information. This requires re-inserting the expected field label (with type name) to the right place with the block label.

Examples:

Focusing full-block field, number top block

Focusing full-block field, child

Information shortcut, shadow

Focusing full-block field, dropdown top block

Information shortcut

Focusing full-block field

Information shortcut, disabled

Extended Information shortcut

Labels are also refreshed automatically when block context changes: BlockSvg delegates aria recomputation to the full-block field on connect/disconnect (setParent) and after drag ends (setDragging(false)), with tests for those paths.

Reason for Changes

Blocks that are full-block field blocks get special cased in block aria composer, but the special case didn't include adding things like "begin stack", "disabled", the custom input name, etc if they are relevant to the block.

Test Coverage

Tests were added that check expected labels for focused blocks similar to those screenshotted above.

[mikeharv]

This admittedly feels a bit janky, but it's needed because getInputLabels will use includeTypeInfo = false for standard verbosity.

[mikeharv]

This is vibes based, but it felt odd to read/hear "Edit Begin stack, number:10..."

[microbit-robert]

I've done some initial testing with these changes in MakeCode. When I refresh the page, I see a lot of full block numbers as block inputs that get the "begin stack" prefix when I think they shouldn't. If I delete the block, then hit undo, the "begin stack" prefix is removed and the input name is added. I'm not sure if there's a timing issue here - perhaps the full block field labels are calculated on load before they are attached to block they are in?

Screen.Recording.2026-06-19.at.13.35.14.mov

[microbit-robert]

This is a really daft example, but it's more likely to happen in MakeCode where we have full block text inputs. If the value of the input matches the input name, then weird things happen to the output. The order of elements is switched and repeated? I don't really know what's happening here.

Screen.Recording.2026-06-19.at.17.20.17.mov

[microbit-robert]

Is it worth adding input names to fields as well? Nice to know what P0 and P1 relate to when I focus them for this block for example?

[microbit-robert]

I ran into another text mangling example and it does seem to depend on the value of the input. I was able to reproduce in the Blockly playground running locally. Some kind of replacement problem maybe? I haven't investigated.

Update: Ahh it's this code. For this example it amounts to "value 1, a".replace("a", "number: a") - it replaces the first "a" in "value".

I've raised #10050 separately.

Screen.Recording.2026-06-22.at.16.34.55.mov

[mikeharv]

Hi @microbit-robert. Thanks for the thorough testing here! I've updated this branch with fixes that should remove the timing problems and text mangling. Please feel free to take another look!