Playwright.Page.Accessibility (playwright v0.1.17-preview-3) View Source

Playwright.Page.Accessibility provides functions for inspecting Chromium's accessibility tree.

The accessibility tree is used by assistive technology such as screen readers or switches.

Accessibility is a very platform-specific thing. On different platforms, there are different screen readers that might have wildly different output.

Rendering engines of Chromium, Firefox and WebKit have a concept of "accessibility tree", which is then translated into different platform-specific APIs. Accessibility namespace gives access to this Accessibility Tree.

Most of the accessibility tree gets filtered out when converting from internal browser AX Tree to Platform-specific AX-Tree or by assistive technologies themselves. By default, Playwright tries to approximate this filtering, exposing only the "interesting" nodes of the tree.

Link to this section Summary

Types

Options given to snapshot/2

Snapshot result returned from snapshot/2

Functions

Captures the current state of the accessibility tree.

Link to this section Types

Specs

options() ::
  %{} | %{interesting_only: boolean(), root: Playwright.ElementHandle.t()}

Options given to snapshot/2

  • :interesting_only - Prune uninteresting nodes from the tree (default: true)
  • :root - The root DOM element for the snapshot (default: page)

Specs

snapshot() :: %{
  name: String.t(),
  description: String.t(),
  role: String.t(),
  value: String.t() | number(),
  children: list(),
  autocomplete: String.t(),
  checked: boolean() | String.t(),
  disabled: boolean(),
  expanded: boolean(),
  focused: boolean(),
  haspopup: String.t(),
  invalid: String.t(),
  keyshortcuts: String.t(),
  level: number(),
  modal: boolean(),
  multiline: boolean(),
  multiselectable: boolean(),
  orientation: String.t(),
  pressed: boolean() | String.t(),
  readonly: boolean(),
  required: boolean(),
  roledescription: String.t(),
  selected: boolean(),
  valuemax: number(),
  valuemin: number(),
  valuetext: String.t()
}

Snapshot result returned from snapshot/2

  • :name - A human readable name for the node
  • :description - An additional human readable description of the node, if applicable
  • :role - The role
  • :value - The current value of the node, if applicable
  • :children - Child nodes, if any, if applicable
  • :autocomplete - What kind of autocomplete is supported by a control, if applicable
  • :checked - Whether the checkbox is checked, or "mixed", if applicable
  • :disabled - Whether the node is disabled, if applicable
  • :expanded - Whether the node is expanded or collapsed, if applicable
  • :focused - Whether the node is focused, if applicable
  • :haspopup - What kind of popup is currently being shown for a node, if applicable
  • :invalid - Whether and in what way this node's value is invalid, if applicable
  • :keyshortcuts - Keyboard shortcuts associated with this node, if applicable
  • :level - The level of a heading, if applicable
  • :modal - Whether the node is modal, if applicable
  • :multiline - Whether the node text input supports multiline, if applicable
  • :multiselectable - Whether more than one child can be selected, if applicable
  • :orientation - Whether the node is oriented horizontally or vertically, if applicable
  • :pressed - Whether the toggle button is checked, or "mixed", if applicable
  • :readonly - Whether the node is read only, if applicable
  • :required - Whether the node is required, if applicable
  • :roledescription - A human readable alternative to the role, if applicable
  • :selected - Whether the node is selected in its parent node, if applicable
  • :valuemax - The maximum value in a node, if applicable
  • :valuemin - The minimum value in a node, if applicable
  • :valuetext - A description of the current value, if applicable

Link to this section Functions

Link to this function

snapshot(page, options \\ %{})

View Source

Specs

snapshot(Playwright.Page.t(), options()) :: snapshot()

Captures the current state of the accessibility tree.

The result represents the root accessible node of the page.

Examples

Dumping an entire accessibility tree:

Browser.new_page(browser)
  |> Page.set_content("<p>Hello!</p>")
  |> Page.Accessibility.snapshot()
%{children: [%{name: "Hello!", role: "text"}], name: "", role: "WebArea"}

Retrieving the name of a focused node:

body = "<input placeholder='pick me' readonly /><input placeholder='not me' />"
Browser.new_page(browser)
  |> Page.set_content(body)
  |> Page.Accessibility.snapshot()
  |> (&(Enum.find(&1.children, fn e -> e.readonly end))).()
%{name: "pick me", readonly: true, role: "textbox"}