/* Utilities related to WAI-ARIA */ const AriaUtils = { /* Tests simple role assignment:
x
Not intended for nested, context-dependent, or other complex role tests. Ex: AriaUtils.assignAndVerifyRolesByRoleNames(["group", "main", "button"]) */ assignAndVerifyRolesByRoleNames: function(roleNames) { if (!Array.isArray(roleNames) || !roleNames.length) { throw `Param roleNames of assignAndVerifyRolesByRoleNames("${roleNames}") should be an array containing at least one role string.`; } for (const role of roleNames) { promise_test(async t => { let el = document.createElement("div"); el.appendChild(document.createTextNode("x")); el.setAttribute("role", role); // el.role not yet supported by Gecko. document.body.appendChild(el); const computedRole = await test_driver.get_computed_role(el); assert_equals(computedRole, role.toLowerCase(), el.outerHTML); }, `role: ${role}`); } }, /* Tests computed ROLE of all elements matching selector against the string value of their data-expectedrole attribute. Ex:
AriaUtils.verifyRolesBySelector(".ex") */ verifyRolesBySelector: function(selector, roleTestNamePrefix) { const els = document.querySelectorAll(selector); if (!els.length) { throw `Selector passed in verifyRolesBySelector("${selector}") should match at least one element.`; } for (const el of els) { if (!el.hasAttribute("data-expectedrole")) { throw `Element should have attribute 'data-expectedrole'. Element: ${el.outerHTML}`; } let role = el.getAttribute("data-expectedrole"); let testName = el.getAttribute("data-testname") || role; // data-testname optional if role is unique per test file if (typeof roleTestNamePrefix !== "undefined") { testName = roleTestNamePrefix + testName; } promise_test(async t => { const expectedRole = el.getAttribute("data-expectedrole"); const computedRole = await test_driver.get_computed_role(el); assert_equals(computedRole, expectedRole, el.outerHTML); }, `${testName}`); } }, /* Tests computed ROLE of selected elements matching selector against the string value of provided roles array. Ex: AriaUtils.verifyRoleOrVariantRolesBySelector(".ex-foo-or-bar", ["fooRole", "barRole"]); See also helper function verifyGenericRolesBySelector shorthand of the above using ["generic", "", "none"]. Note: This function should not be used to circumvent unexpected interop differences in implementations. It should only be used in specific cases (like "generic") determined by ARIA WG or other spec maintainers to be acceptable for the purposes of testing. */ verifyRoleOrVariantRolesBySelector: function(selector, roles) { const els = document.querySelectorAll(selector); if (!els.length) { throw `Selector "${selector}" should match at least one element.`; } if (!roles.length || roles.length < 2) { throw `Roles array ["${roles.join('", "')}"] should include at least two strings, a primary role and at least one acceptable implementation-specific variant. E.g. ["generic", "", "none"]…`; } for (const el of els) { let testName = el.getAttribute("data-testname"); promise_test(async t => { const expectedRoles = roles; const computedRole = await test_driver.get_computed_role(el); for (role of roles){ if (computedRole === role) { return assert_equals(computedRole, role, `Computed Role: "${computedRole}" matches one of the acceptable role strings in ["${roles.join('", "')}"]: ${el.outerHTML}`); } } return assert_false(true, `Computed Role: "${computedRole}" does not match any of the acceptable role strings in ["${roles.join('", "')}"]: ${el.outerHTML}`); }, `${testName}`); } }, /* Helper function for "generic" ROLE tests. Ex: AriaUtils.verifyGenericRolesBySelector(".ex-generic"); This helper function is equivalant to AriaUtils.verifyRoleOrVariantRolesBySelector(".ex-generic", ["generic", "", "none"]); See various issues and discussions linked from https://github.com/web-platform-tests/interop-accessibility/issues/48 */ verifyGenericRolesBySelector: function(selector) { // ARIA WG determined implementation variants "none" (Chromium), and the empty string "" (WebKit), are sufficiently equivalent to "generic" for WPT test verification of HTML-AAM. // See various discussions linked from https://github.com/web-platform-tests/interop-accessibility/issues/48 this.verifyRoleOrVariantRolesBySelector(selector, ["generic", "", "none"]); }, /* Tests computed LABEL of all elements matching selector against the string value of their data-expectedlabel attribute. Ex:
AriaUtils.verifyLabelsBySelector(".ex") */ verifyLabelsBySelector: function(selector, labelTestNamePrefix) { const els = document.querySelectorAll(selector); if (!els.length) { throw `Selector passed in verifyLabelsBySelector("${selector}") should match at least one element.`; } for (const el of els) { if (!el.hasAttribute("data-expectedlabel")) { throw `Element should have attribute 'data-expectedlabel'. Element: ${el.outerHTML}`; } let label = el.getAttribute("data-expectedlabel"); let testName = el.getAttribute("data-testname") || label; // data-testname optional if label is unique per test file if (typeof labelTestNamePrefix !== "undefined") { testName = labelTestNamePrefix + testName; } promise_test(async t => { const expectedLabel = el.getAttribute("data-expectedlabel"); let computedLabel = await test_driver.get_computed_label(el); assert_not_equals(computedLabel, null, `get_computed_label(el) shouldn't return null for ${el.outerHTML}`); // See: // - https://github.com/w3c/accname/pull/165 // - https://github.com/w3c/accname/issues/192 // - https://github.com/w3c/accname/issues/208 // // AccName references HTML's definition of ASCII Whitespace // https://infra.spec.whatwg.org/#ascii-whitespace // which matches tab (\t), newline (\n), formfeed (\f), return (\r), and regular space (\u0020). // but it does NOT match non-breaking space (\xA0,\u00A0) and others matched by \s const asciiWhitespace = /[\t\n\f\r\u0020]+/g; computedLabel = computedLabel.replace(asciiWhitespace, '\u0020').replace(/^\u0020|\u0020$/g, ''); assert_equals(computedLabel, expectedLabel, el.outerHTML); }, `${testName}`); } }, /* Tests computed LABEL and ROLE of all elements matching selector using existing verifyLabelsBySelector(), verifyRolesBySelector() functions and passes a test name prefix to ensure uniqueness. Ex:
AriaUtils.verifyRolesAndLabelsBySelector(".ex-role-and-label") */ verifyRolesAndLabelsBySelector: function(selector) { let labelTestNamePrefix = "Label: "; let roleTestNamePrefix = "Role: "; const els = document.querySelectorAll(selector); if (!els.length) { throw `Selector passed in verifyRolesAndLabelsBySelector("${selector}") should match at least one element.`; } for (const el of els) { el.classList.add("ex-label-only"); el.classList.add("ex-role-only"); } this.verifyLabelsBySelector(".ex-label-only", labelTestNamePrefix); this.verifyRolesBySelector(".ex-role-only", roleTestNamePrefix); }, /* Tests accessibility properties of all elements matching selector against the expected properties specified using JSON in their data-expected attribute. For example:
foo
... AriaUtils.verifyPropertiesBySelector(".ex-props"); */ verifyPropertiesBySelector: function(selector) { const els = document.querySelectorAll(selector); if (!els.length) { throw `Selector passed in verifyPropertiesBySelector("${selector}") should match at least one element.`; } for (const el of els) { const expected = JSON.parse(el.getAttribute("data-expectedproperties")); const testName = el.getAttribute("data-testname"); promise_test(async t => { const actual = await test_driver.get_accessibility_properties_for_element(el); for (const key in expected) { assert_equals(actual[key], expected[key], `${key}: ${el.outerHTML}`); } }, testName); } }, /* Verifies that the subtree for a given accessible node matches the specified tree structure. This takes either a DOM Element or a CSS selector. It wraps the call in promise_test. For example:
... AriaUtils.verifyAccessibilitySubtree("#listbox", { role: "listbox", label: "listbox", children: [ { role: "option", label: "option1", children: [] }, { role: "option", label: "option2", children: [] }, ], }); Note that there can be differences in the structure of the accessibility tree across browser engines for various valid reasons. This should only be used to test a subtree where the structure of that subtree has been explicitly standardized with consensus from multiple browser vendors. */ verifyAccessibilitySubtree: function(subtreeRoot, expectedTree) { const desc = subtreeRoot; if (typeof subtreeRoot == "string") { subtreeRoot = document.querySelector(subtreeRoot); if (!subtreeRoot) { throw `selector passed to verifyAccessibilitySubtree("${subtreeRoot}") doesn't match an element`; } } promise_test(async t => { const acc = await test_driver.get_accessibility_properties_for_element(subtreeRoot); await AriaUtils._assertAccessibilitySubtree(acc, expectedTree, desc); }, `accessibility tree for ${desc}`); }, /* Helper function called recursively to assert that the subtree for a given accessible node matches the specified tree structure. This is initiated by verifyAccessibilitySubtree. It takes an accessible properties object, the expected tree structure and a string describing the element to be used as the prefix for assertion messages. For example:
...
... const listbox = await test_driver.get_accessibility_properties_for_element(document.getElementById("listbox")); await AriaUtils.assertAccessibilitySubtree(listbox, { ... }, "#listbox"); */ _assertAccessibilitySubtree: async function(accProps, expectedTree, position) { for (const key in expectedTree) { if (key == "children") { assert_equals( accProps.children.length, expectedTree.children.length, `${position} children.length` ); for (let c = 0; c < accProps.children.length; ++c) { const childId = accProps.children[c]; const childAcc = await test_driver.get_accessibility_properties_for_accessibility_node(childId); await AriaUtils._assertAccessibilitySubtree( childAcc, expectedTree.children[c], `${position}[${c}]` ); } continue; } assert_equals(accProps[key], expectedTree[key], `${position} ${key}`); } }, };