Bug 1540904 - added full page API for accessibility walker actor. r=pbro

Differential Revision: https://phabricator.services.mozilla.com/D26458

--HG--
extra : moz-landing-system : lando

devtools/server/actors/accessibility/walker.js

@@ -122,6 +122,27 @@ function isStale(accessible) {
   return !!(extraState.value & Ci.nsIAccessibleStates.EXT_STATE_STALE);
 }
 
+/**
+ * Get accessibility audit starting with the passed accessible object as a root.
+ *
+ * @param {Object} acc
+ *        AccessibileActor to be used as the root for the audit.
+ * @param {Map} report
+ *        An accumulator map to be used to store audit information.
+ */
+function getAudit(acc, report) {
+  if (acc.isDefunct) {
+    return;
+  }
+
+  // Audit returns a promise, save the actual value in the report.
+  report.set(acc, acc.audit().then(result => report.set(acc, result)));
+
+  for (const child of acc.children()) {
+    getAudit(child, report);
+  }
+}
+
 /**
  * The AccessibleWalkerActor stores a cache of AccessibleActors that represent
  * accessible objects in a given document.
@@ -367,6 +388,30 @@ const AccessibleWalkerActor = ActorClassWithSpec(accessibleWalkerSpec, {
       { accessible: parent, children: parent.children() }));
   },
 
+  /**
+   * Run accessibility audit and return relevant ancestries for AccessibleActors
+   * that have non-empty audit checks.
+   *
+   * @return {Promise}
+   *         A promise that resolves when the audit is complete and all relevant
+   *         ancestries are calculated.
+   */
+  async audit() {
+    const doc = await this.getDocument();
+    const report = new Map();
+    getAudit(doc, report);
+    await Promise.all(report.values());
+
+    const ancestries = [];
+    for (const [acc, audit] of report.entries()) {
+      if (audit && Object.values(audit).filter(check => check != null).length > 0) {
+        ancestries.push(this.getAncestry(acc));
+      }
+    }
+
+    return Promise.all(ancestries);
+  },
+
   onHighlighterEvent: function(data) {
     this.emit("highlighter-event", data);
   },

devtools/server/tests/browser/browser.ini

@@ -5,6 +5,7 @@ support-files =
   head.js
   animation.html
   animation-data.html
+  doc_accessibility_audit.html
   doc_accessibility_infobar.html
   doc_accessibility.html
   doc_allocations.html
@@ -47,6 +48,7 @@ skip-if = (os == 'win' && processor == 'aarch64') # bug 1533184
 skip-if = (os == 'win' && processor == 'aarch64') # bug 1533184
 [browser_accessibility_simple.js]
 skip-if = (os == 'win' && processor == 'aarch64') # bug 1533184
+[browser_accessibility_walker_audit.js]
 [browser_accessibility_walker.js]
 skip-if = (os == 'win' && processor == 'aarch64') # bug 1533487
 [browser_actor_error.js]

devtools/server/tests/browser/browser_accessibility_walker_audit.js

@@ -0,0 +1,163 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+// Checks for the AccessibleWalkerActor audit.
+add_task(async function() {
+  const {target, accessibility} =
+    await initAccessibilityFrontForUrl(MAIN_DOMAIN + "doc_accessibility_audit.html");
+
+  const accessibles = [{
+    name: "",
+    role: "document",
+    value: "",
+    description: "",
+    keyboardShortcut: "",
+    childCount: 2,
+    domNodeType: 9,
+    indexInParent: 0,
+    states: [
+      "focused", "readonly", "focusable", "active", "opaque", "enabled", "sensitive",
+    ],
+    actions: [],
+    attributes: {
+      display: "block",
+      "explicit-name": "true",
+      "margin-bottom": "8px",
+      "margin-left": "8px",
+      "margin-right": "8px",
+      "margin-top": "8px",
+      tag: "body",
+      "text-align": "start",
+      "text-indent": "0px",
+    },
+    checks: {
+      "CONTRAST": null,
+    },
+  }, {
+    name: "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do " +
+          "eiusmod tempor incididunt ut labore et dolore magna aliqua.",
+    role: "heading",
+    value: "",
+    description: "",
+    keyboardShortcut: "",
+    childCount: 1,
+    domNodeType: 1,
+    indexInParent: 0,
+    states: [ "selectable text", "opaque", "enabled", "sensitive" ],
+    actions: [],
+    attributes: {
+      display: "block",
+      formatting: "block",
+      id: "h1",
+      level: "1",
+      "margin-bottom": "21.4333px",
+      "margin-left": "0px",
+      "margin-right": "0px",
+      "margin-top": "21.4333px",
+      tag: "h1",
+      "text-align": "start",
+      "text-indent": "0px",
+    },
+    checks: {
+      "CONTRAST": null,
+    },
+  }, {
+    name: "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do " +
+           "eiusmod tempor incididunt ut labore et dolore magna aliqua.",
+    role: "text leaf",
+    value: "",
+    description: "",
+    keyboardShortcut: "",
+    childCount: 0,
+    domNodeType: 3,
+    indexInParent: 0,
+    states: [ "opaque", "enabled", "sensitive" ],
+    actions: [],
+    attributes: { "explicit-name": "true" },
+    checks: {
+      "CONTRAST": {
+        "value": 21,
+        "color": [0, 0, 0, 1],
+        "backgroundColor": [255, 255, 255, 1],
+        "isLargeText": true,
+      },
+    },
+  }, {
+    name: "",
+    role: "paragraph",
+    value: "",
+    description: "",
+    keyboardShortcut: "",
+    childCount: 1,
+    domNodeType: 1,
+    indexInParent: 1,
+    states: [ "selectable text", "opaque", "enabled", "sensitive" ],
+    actions: [ "Press" ],
+    attributes: {
+      display: "block",
+      formatting: "block",
+      id: "p",
+      "margin-bottom": "16px",
+      "margin-left": "0px",
+      "margin-right": "0px",
+      "margin-top": "16px",
+      tag: "p",
+      "text-align": "start",
+      "text-indent": "0px",
+    },
+    checks: {
+      "CONTRAST": null,
+    },
+  }, {
+    name: "Accessible Paragraph",
+    role: "text leaf",
+    value: "",
+    description: "",
+    keyboardShortcut: "",
+    childCount: 0,
+    domNodeType: 3,
+    indexInParent: 0,
+    states: [ "opaque", "enabled", "sensitive" ],
+    actions: [],
+    attributes: { "explicit-name": "true" },
+    checks: {
+      "CONTRAST": {
+        "value": 21,
+        "color": [0, 0, 0, 1],
+        "backgroundColor": [255, 255, 255, 1],
+        "isLargeText": false,
+      },
+    },
+  }];
+
+  function findAccessible(name, role) {
+    return accessibles.find(accessible =>
+      accessible.name === name && accessible.role === role);
+  }
+
+  const a11yWalker = await accessibility.getWalker();
+  ok(a11yWalker, "The AccessibleWalkerFront was returned");
+  await accessibility.enable();
+
+  info("Checking AccessibleWalker audit functionality");
+  const ancestries = await a11yWalker.audit();
+
+  for (const ancestry of ancestries) {
+    for (const { accessible, children } of ancestry) {
+      checkA11yFront(accessible,
+                     findAccessible(accessibles.name, accessibles.role));
+      for (const child of children) {
+        checkA11yFront(child,
+                       findAccessible(child.name, child.role));
+      }
+    }
+  }
+
+  await accessibility.disable();
+  await waitForA11yShutdown();
+  await target.destroy();
+  gBrowser.removeCurrentTab();
+});

devtools/server/tests/browser/doc_accessibility_audit.html

@@ -0,0 +1,10 @@
+<!DOCTYPE HTML>
+<html>
+  <head>
+    <meta charset="utf-8">
+  </head>
+<body>
+  <h1 id="h1">Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.</h1>
+  <p id="p">Accessible Paragraph</p>
+</body>
+</html>

devtools/server/tests/browser/head.js

@@ -272,7 +272,7 @@ function checkA11yFront(front, expected, expectedFront) {
   }
 
   for (const key in expected) {
-    if (["actions", "states", "attributes"].includes(key)) {
+    if (["actions", "states", "attributes", "checks"].includes(key)) {
       SimpleTest.isDeeply(front[key], expected[key],
         `Accessible Front has correct ${key}`);
     } else {

devtools/shared/specs/accessibility.js

@@ -162,6 +162,12 @@ const accessibleWalkerSpec = generateActorSpec({
         ancestry: RetVal("array:accessibleWithChildren"),
       },
     },
+    audit: {
+      request: {},
+      response: {
+        audit: RetVal("array:array:accessibleWithChildren"),
+      },
+    },
     highlightAccessible: {
       request: {
         accessible: Arg(0, "accessible"),