a11y(Alert): give Alert alertdialog role

[bvandercar-vt]

Checklist

• [N/A] Includes tests
• [N/A] Update documentation

Changes proposed in this pull request:

1. Make Dialog role prop configurable (default="dialog")
2. Set Alert's Dialog's role to alertdialog: https://developer.mozilla.org/en-US/docs/Web/Accessibility/ARIA/Roles/alertdialog_role

[changelog-app]

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Type

• Feature
• Improvement
• Fix
• Break
• Deprecation
• Manual task
• Migration

Description

feat(a11y): give Alert alertdialog role

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[evansjohnson]

We may also want to set aria-modal="true" when setting this role

---

We may also want to follow this guidance if adding this role

The alert dialog must have at least one focusable control — such as Confirm, Close, and Cancel — and focus must be moved to that control when the alert dialog appears. Alertdialogs can have additional interactive controls such as text fields and checkboxes.

From my logging it appears focus is initially on the start of the dialog focus trap

[bvandercar-vt]

Good call. Tied aria-modal to the enforceFocus prop in Dialog, these seemed to be one in the same. 1a9709b

[evansjohnson]

Could we have an explicit list of values we expect to be valid given the setup of this component? "dialog" | "alertdialog" feels like a reasonable place to start that can be expanded as needed.

[bvandercar-vt]

97104bb

[evansjohnson]

LGTM