Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

4 files changed, 1270 insertions, 0 deletions

diff --git a/devtools/server/actors/accessibility/audit/contrast.js b/devtools/server/actors/accessibility/audit/contrast.js
new file mode 100644
index 0000000000..68e7b497f8
--- /dev/null
+++ b/devtools/server/actors/accessibility/audit/contrast.js
@@ -0,0 +1,306 @@
+/* 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";
+
+loader.lazyRequireGetter(
+  this,
+  "CssLogic",
+  "resource://devtools/server/actors/inspector/css-logic.js",
+  true
+);
+loader.lazyRequireGetter(
+  this,
+  "getCurrentZoom",
+  "resource://devtools/shared/layout/utils.js",
+  true
+);
+loader.lazyRequireGetter(
+  this,
+  "addPseudoClassLock",
+  "resource://devtools/server/actors/highlighters/utils/markup.js",
+  true
+);
+loader.lazyRequireGetter(
+  this,
+  "removePseudoClassLock",
+  "resource://devtools/server/actors/highlighters/utils/markup.js",
+  true
+);
+loader.lazyRequireGetter(
+  this,
+  "getContrastRatioAgainstBackground",
+  "resource://devtools/shared/accessibility.js",
+  true
+);
+loader.lazyRequireGetter(
+  this,
+  "getTextProperties",
+  "resource://devtools/shared/accessibility.js",
+  true
+);
+loader.lazyRequireGetter(
+  this,
+  "DevToolsWorker",
+  "resource://devtools/shared/worker/worker.js",
+  true
+);
+loader.lazyRequireGetter(
+  this,
+  "InspectorActorUtils",
+  "resource://devtools/server/actors/inspector/utils.js"
+);
+
+const WORKER_URL = "resource://devtools/server/actors/accessibility/worker.js";
+const HIGHLIGHTED_PSEUDO_CLASS = ":-moz-devtools-highlighted";
+const {
+  LARGE_TEXT: { BOLD_LARGE_TEXT_MIN_PIXELS, LARGE_TEXT_MIN_PIXELS },
+} = require("resource://devtools/shared/accessibility.js");
+
+loader.lazyGetter(this, "worker", () => new DevToolsWorker(WORKER_URL));
+
+/**
+ * Get canvas rendering context for the current target window bound by the bounds of the
+ * accessible objects.
+ * @param  {Object}  win
+ *         Current target window.
+ * @param  {Object}  bounds
+ *         Bounds for the accessible object.
+ * @param  {Object}  zoom
+ *         Current zoom level for the window.
+ * @param  {Object}  scale
+ *         Scale value to scale down the drawn image.
+ * @param  {null|DOMNode} node
+ *         If not null, a node that corresponds to the accessible object to be used to
+ *         make its text color transparent.
+ * @return {CanvasRenderingContext2D}
+ *         Canvas rendering context for the current window.
+ */
+function getImageCtx(win, bounds, zoom, scale, node) {
+  const doc = win.document;
+  const canvas = doc.createElementNS("http://www.w3.org/1999/xhtml", "canvas");
+
+  const { left, top, width, height } = bounds;
+  canvas.width = width * zoom * scale;
+  canvas.height = height * zoom * scale;
+  const ctx = canvas.getContext("2d", { alpha: false });
+  ctx.imageSmoothingEnabled = false;
+  ctx.scale(scale, scale);
+
+  // If node is passed, make its color related text properties invisible.
+  if (node) {
+    addPseudoClassLock(node, HIGHLIGHTED_PSEUDO_CLASS);
+  }
+
+  ctx.drawWindow(
+    win,
+    left * zoom,
+    top * zoom,
+    width * zoom,
+    height * zoom,
+    "#fff",
+    ctx.DRAWWINDOW_USE_WIDGET_LAYERS
+  );
+
+  // Restore all inline styling.
+  if (node) {
+    removePseudoClassLock(node, HIGHLIGHTED_PSEUDO_CLASS);
+  }
+
+  return ctx;
+}
+
+/**
+ * Calculate the transformed RGBA when a color matrix is set in docShell by
+ * multiplying the color matrix with the RGBA vector.
+ *
+ * @param  {Array}  rgba
+ *         Original RGBA array which we want to transform.
+ * @param  {Array}  colorMatrix
+ *         Flattened 4x5 color matrix that is set in docShell.
+ *         A 4x5 matrix of the form:
+ *           1  2  3  4  5
+ *           6  7  8  9  10
+ *           11 12 13 14 15
+ *           16 17 18 19 20
+ *         will be set in docShell as:
+ *           [1, 6, 11, 16, 2, 7, 12, 17, 3, 8, 13, 18, 4, 9, 14, 19, 5, 10, 15, 20]
+ * @return {Array}
+ *         Transformed RGBA after the color matrix is multiplied with the original RGBA.
+ */
+function getTransformedRGBA(rgba, colorMatrix) {
+  const transformedRGBA = [0, 0, 0, 0];
+
+  // Only use the first four columns of the color matrix corresponding to R, G, B and A
+  // color channels respectively. The fifth column is a fixed offset that does not need
+  // to be considered for the matrix multiplication. We end up multiplying a 4x4 color
+  // matrix with a 4x1 RGBA vector.
+  for (let i = 0; i < 16; i++) {
+    const row = i % 4;
+    const col = Math.floor(i / 4);
+    transformedRGBA[row] += colorMatrix[i] * rgba[col];
+  }
+
+  return transformedRGBA;
+}
+
+/**
+ * Find RGBA or a range of RGBAs for the background pixels under the text.
+ *
+ * @param  {DOMNode}  node
+ *         Node for which we want to get the background color data.
+ * @param  {Object}  options
+ *         - bounds       {Object}
+ *                        Bounds for the accessible object.
+ *         - win          {Object}
+ *                        Target window.
+ *         - size         {Number}
+ *                        Font size of the selected text node
+ *         - isBoldText   {Boolean}
+ *                        True if selected text node is bold
+ * @return {Object}
+ *         Object with one or more of the following RGBA fields: value, min, max
+ */
+function getBackgroundFor(node, { win, bounds, size, isBoldText }) {
+  const zoom = 1 / getCurrentZoom(win);
+  // When calculating colour contrast, we traverse image data for text nodes that are
+  // drawn both with and without transparent text. Image data arrays are typically really
+  // big. In cases when the font size is fairly large or when the page is zoomed in image
+  // data is especially large (retrieving it and/or traversing it takes significant amount
+  // of time). Here we optimize the size of the image data by scaling down the drawn nodes
+  // to a size where their text size equals either BOLD_LARGE_TEXT_MIN_PIXELS or
+  // LARGE_TEXT_MIN_PIXELS (lower threshold for large text size) depending on the font
+  // weight.
+  //
+  // IMPORTANT: this optimization, in some cases where background colour is non-uniform
+  // (gradient or image), can result in small (not noticeable) blending of the background
+  // colours. In turn this might affect the reported values of the contrast ratio. The
+  // delta is fairly small (<0.1) to noticeably skew the results.
+  //
+  // NOTE: this optimization does not help in cases where contrast is being calculated for
+  // nodes with a lot of text.
+  let scale =
+    ((isBoldText ? BOLD_LARGE_TEXT_MIN_PIXELS : LARGE_TEXT_MIN_PIXELS) / size) *
+    zoom;
+  // We do not need to scale the images if the font is smaller than large or if the page
+  // is zoomed out (scaling in this case would've been scaling up).
+  scale = scale > 1 ? 1 : scale;
+
+  const textContext = getImageCtx(win, bounds, zoom, scale);
+  const backgroundContext = getImageCtx(win, bounds, zoom, scale, node);
+
+  const { data: dataText } = textContext.getImageData(
+    0,
+    0,
+    bounds.width * scale,
+    bounds.height * scale
+  );
+  const { data: dataBackground } = backgroundContext.getImageData(
+    0,
+    0,
+    bounds.width * scale,
+    bounds.height * scale
+  );
+
+  return worker.performTask(
+    "getBgRGBA",
+    {
+      dataTextBuf: dataText.buffer,
+      dataBackgroundBuf: dataBackground.buffer,
+    },
+    [dataText.buffer, dataBackground.buffer]
+  );
+}
+
+/**
+ * Calculates the contrast ratio of the referenced DOM node.
+ *
+ * @param  {DOMNode} node
+ *         The node for which we want to calculate the contrast ratio.
+ * @param  {Object}  options
+ *         - bounds                           {Object}
+ *                                            Bounds for the accessible object.
+ *         - win                              {Object}
+ *                                            Target window.
+ *         - appliedColorMatrix               {Array|null}
+ *                                            Simulation color matrix applied to
+ *                                            to the viewport, if it exists.
+ * @return {Object}
+ *         An object that may contain one or more of the following fields: error,
+ *         isLargeText, value, min, max values for contrast.
+ */
+async function getContrastRatioFor(node, options = {}) {
+  const computedStyle = CssLogic.getComputedStyle(node);
+  const props = computedStyle ? getTextProperties(computedStyle) : null;
+
+  if (!props) {
+    return {
+      error: true,
+    };
+  }
+
+  const { isLargeText, isBoldText, size, opacity } = props;
+  const { appliedColorMatrix } = options;
+  const color = appliedColorMatrix
+    ? getTransformedRGBA(props.color, appliedColorMatrix)
+    : props.color;
+  let rgba = await getBackgroundFor(node, {
+    ...options,
+    isBoldText,
+    size,
+  });
+
+  if (!rgba) {
+    // Fallback (original) contrast calculation algorithm. It tries to get the
+    // closest background colour for the node and use it to calculate contrast.
+    const backgroundColor = InspectorActorUtils.getClosestBackgroundColor(node);
+    const backgroundImage = InspectorActorUtils.getClosestBackgroundImage(node);
+
+    if (backgroundImage !== "none") {
+      // Both approaches failed, at this point we don't have a better one yet.
+      return {
+        error: true,
+      };
+    }
+
+    let { r, g, b, a } = InspectorUtils.colorToRGBA(backgroundColor);
+    // If the element has opacity in addition to background alpha value, take it
+    // into account. TODO: this does not handle opacity set on ancestor
+    // elements (see bug https://bugzilla.mozilla.org/show_bug.cgi?id=1544721).
+    if (opacity < 1) {
+      a = opacity * a;
+    }
+
+    return getContrastRatioAgainstBackground(
+      {
+        value: appliedColorMatrix
+          ? getTransformedRGBA([r, g, b, a], appliedColorMatrix)
+          : [r, g, b, a],
+      },
+      {
+        color,
+        isLargeText,
+      }
+    );
+  }
+
+  if (appliedColorMatrix) {
+    rgba = rgba.value
+      ? {
+          value: getTransformedRGBA(rgba.value, appliedColorMatrix),
+        }
+      : {
+          min: getTransformedRGBA(rgba.min, appliedColorMatrix),
+          max: getTransformedRGBA(rgba.max, appliedColorMatrix),
+        };
+  }
+
+  return getContrastRatioAgainstBackground(rgba, {
+    color,
+    isLargeText,
+  });
+}
+
+exports.getContrastRatioFor = getContrastRatioFor;
+exports.getBackgroundFor = getBackgroundFor;
diff --git a/devtools/server/actors/accessibility/audit/keyboard.js b/devtools/server/actors/accessibility/audit/keyboard.js
new file mode 100644
index 0000000000..d1b13dbbf6
--- /dev/null
+++ b/devtools/server/actors/accessibility/audit/keyboard.js
@@ -0,0 +1,514 @@
+/* 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";
+
+loader.lazyRequireGetter(
+  this,
+  "CssLogic",
+  "resource://devtools/server/actors/inspector/css-logic.js",
+  true
+);
+loader.lazyRequireGetter(
+  this,
+  "getCSSStyleRules",
+  "resource://devtools/shared/inspector/css-logic.js",
+  true
+);
+loader.lazyRequireGetter(
+  this,
+  "nodeConstants",
+  "resource://devtools/shared/dom-node-constants.js"
+);
+loader.lazyRequireGetter(
+  this,
+  ["isDefunct", "getAriaRoles"],
+  "resource://devtools/server/actors/utils/accessibility.js",
+  true
+);
+
+const {
+  accessibility: {
+    AUDIT_TYPE: { KEYBOARD },
+    ISSUE_TYPE: {
+      [KEYBOARD]: {
+        FOCUSABLE_NO_SEMANTICS,
+        FOCUSABLE_POSITIVE_TABINDEX,
+        INTERACTIVE_NO_ACTION,
+        INTERACTIVE_NOT_FOCUSABLE,
+        MOUSE_INTERACTIVE_ONLY,
+        NO_FOCUS_VISIBLE,
+      },
+    },
+    SCORES: { FAIL, WARNING },
+  },
+} = require("resource://devtools/shared/constants.js");
+
+// Specified by the author CSS rule type.
+const STYLE_RULE = 1;
+
+// Accessible action for showing long description.
+const CLICK_ACTION = "click";
+
+/**
+ * Focus specific pseudo classes that the keyboard audit simulates to determine
+ * focus styling.
+ */
+const FOCUS_PSEUDO_CLASS = ":focus";
+const MOZ_FOCUSRING_PSEUDO_CLASS = ":-moz-focusring";
+
+const KEYBOARD_FOCUSABLE_ROLES = new Set([
+  Ci.nsIAccessibleRole.ROLE_BUTTONMENU,
+  Ci.nsIAccessibleRole.ROLE_CHECKBUTTON,
+  Ci.nsIAccessibleRole.ROLE_COMBOBOX,
+  Ci.nsIAccessibleRole.ROLE_EDITCOMBOBOX,
+  Ci.nsIAccessibleRole.ROLE_ENTRY,
+  Ci.nsIAccessibleRole.ROLE_LINK,
+  Ci.nsIAccessibleRole.ROLE_LISTBOX,
+  Ci.nsIAccessibleRole.ROLE_PASSWORD_TEXT,
+  Ci.nsIAccessibleRole.ROLE_PUSHBUTTON,
+  Ci.nsIAccessibleRole.ROLE_RADIOBUTTON,
+  Ci.nsIAccessibleRole.ROLE_SLIDER,
+  Ci.nsIAccessibleRole.ROLE_SPINBUTTON,
+  Ci.nsIAccessibleRole.ROLE_SUMMARY,
+  Ci.nsIAccessibleRole.ROLE_SWITCH,
+  Ci.nsIAccessibleRole.ROLE_TOGGLE_BUTTON,
+]);
+
+const INTERACTIVE_ROLES = new Set([
+  ...KEYBOARD_FOCUSABLE_ROLES,
+  Ci.nsIAccessibleRole.ROLE_CHECK_MENU_ITEM,
+  Ci.nsIAccessibleRole.ROLE_CHECK_RICH_OPTION,
+  Ci.nsIAccessibleRole.ROLE_COMBOBOX_OPTION,
+  Ci.nsIAccessibleRole.ROLE_MENUITEM,
+  Ci.nsIAccessibleRole.ROLE_OPTION,
+  Ci.nsIAccessibleRole.ROLE_OUTLINE,
+  Ci.nsIAccessibleRole.ROLE_OUTLINEITEM,
+  Ci.nsIAccessibleRole.ROLE_PAGETAB,
+  Ci.nsIAccessibleRole.ROLE_PARENT_MENUITEM,
+  Ci.nsIAccessibleRole.ROLE_RADIO_MENU_ITEM,
+  Ci.nsIAccessibleRole.ROLE_RICH_OPTION,
+]);
+
+const INTERACTIVE_IF_FOCUSABLE_ROLES = new Set([
+  // If article is focusable, we can assume it is inside a feed.
+  Ci.nsIAccessibleRole.ROLE_ARTICLE,
+  // Column header can be focusable.
+  Ci.nsIAccessibleRole.ROLE_COLUMNHEADER,
+  Ci.nsIAccessibleRole.ROLE_GRID_CELL,
+  Ci.nsIAccessibleRole.ROLE_MENUBAR,
+  Ci.nsIAccessibleRole.ROLE_MENUPOPUP,
+  Ci.nsIAccessibleRole.ROLE_PAGETABLIST,
+  // Row header can be focusable.
+  Ci.nsIAccessibleRole.ROLE_ROWHEADER,
+  Ci.nsIAccessibleRole.ROLE_SCROLLBAR,
+  Ci.nsIAccessibleRole.ROLE_SEPARATOR,
+  Ci.nsIAccessibleRole.ROLE_TOOLBAR,
+]);
+
+/**
+ * Determine if a node is dead or is not an element node.
+ *
+ * @param   {DOMNode} node
+ *          Node to be tested for validity.
+ *
+ * @returns {Boolean}
+ *          True if the node is either dead or is not an element node.
+ */
+function isInvalidNode(node) {
+  return (
+    !node ||
+    Cu.isDeadWrapper(node) ||
+    node.nodeType !== nodeConstants.ELEMENT_NODE ||
+    !node.ownerGlobal
+  );
+}
+
+/**
+ * Determine if accessible is focusable with the keyboard.
+ *
+ * @param   {nsIAccessible} accessible
+ *          Accessible for which to determine if it is keyboard focusable.
+ *
+ * @returns {Boolean}
+ *          True if focusable with the keyboard.
+ */
+function isKeyboardFocusable(accessible) {
+  const state = {};
+  accessible.getState(state, {});
+  // State will be focusable even if the tabindex is negative.
+  return (
+    state.value & Ci.nsIAccessibleStates.STATE_FOCUSABLE &&
+    // Platform accessibility will still report STATE_FOCUSABLE even with the
+    // tabindex="-1" so we need to check that it is >= 0 to be considered
+    // keyboard focusable.
+    accessible.DOMNode.tabIndex > -1
+  );
+}
+
+/**
+ * Determine if a current node has focus specific styling by applying a
+ * focus-related pseudo class (such as :focus or :-moz-focusring) to a focusable
+ * node.
+ *
+ * @param   {DOMNode} focusableNode
+ *          Node to apply focus-related pseudo class to.
+ * @param   {DOMNode} currentNode
+ *          Node to be checked for having focus specific styling.
+ * @param   {String} pseudoClass
+ *          A focus related pseudo-class to be simulated for style comparison.
+ *
+ * @returns {Boolean}
+ *          True if the currentNode has focus specific styling.
+ */
+function hasStylesForFocusRelatedPseudoClass(
+  focusableNode,
+  currentNode,
+  pseudoClass
+) {
+  const defaultRules = getCSSStyleRules(currentNode);
+
+  InspectorUtils.addPseudoClassLock(focusableNode, pseudoClass);
+
+  // Determine a set of properties that are specific to CSS rules that are only
+  // present when a focus related pseudo-class is locked in.
+  const tempRules = getCSSStyleRules(currentNode);
+  const properties = new Set();
+  for (const rule of tempRules) {
+    if (rule.type !== STYLE_RULE) {
+      continue;
+    }
+
+    if (!defaultRules.includes(rule)) {
+      for (let index = 0; index < rule.style.length; index++) {
+        properties.add(rule.style.item(index));
+      }
+    }
+  }
+
+  // If there are no focus specific CSS rules or properties, currentNode does
+  // node have any focus specific styling, we are done.
+  if (properties.size === 0) {
+    InspectorUtils.removePseudoClassLock(focusableNode, pseudoClass);
+    return false;
+  }
+
+  // Determine values for properties that are focus specific.
+  const tempStyle = CssLogic.getComputedStyle(currentNode);
+  const focusStyle = {};
+  for (const name of properties.values()) {
+    focusStyle[name] = tempStyle.getPropertyValue(name);
+  }
+
+  InspectorUtils.removePseudoClassLock(focusableNode, pseudoClass);
+
+  // If values for focus specific properties are different from default style
+  // values, assume we have focus spefic styles for the currentNode.
+  const defaultStyle = CssLogic.getComputedStyle(currentNode);
+  for (const name of properties.values()) {
+    if (defaultStyle.getPropertyValue(name) !== focusStyle[name]) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
+/**
+ * Check if an element node (currentNode) has distinct focus styling. This
+ * function also takes into account a case when focus styling is applied to a
+ * descendant too.
+ *
+ * @param   {DOMNode} focusableNode
+ *          Node to apply focus-related pseudo class to.
+ * @param   {DOMNode} currentNode
+ *          Node to be checked for having focus specific styling.
+ *
+ * @returns {Boolean}
+ *          True if the node or its descendant has distinct focus styling.
+ */
+function hasFocusStyling(focusableNode, currentNode) {
+  if (isInvalidNode(currentNode)) {
+    return false;
+  }
+
+  // Check if an element node has distinct :-moz-focusring styling.
+  const hasStylesForMozFocusring = hasStylesForFocusRelatedPseudoClass(
+    focusableNode,
+    currentNode,
+    MOZ_FOCUSRING_PSEUDO_CLASS
+  );
+  if (hasStylesForMozFocusring) {
+    return true;
+  }
+
+  // Check if an element node has distinct :focus styling.
+  const hasStylesForFocus = hasStylesForFocusRelatedPseudoClass(
+    focusableNode,
+    currentNode,
+    FOCUS_PSEUDO_CLASS
+  );
+  if (hasStylesForFocus) {
+    return true;
+  }
+
+  // If no element specific focus styles where found, check if its element
+  // children have them.
+  for (
+    let child = currentNode.firstElementChild;
+    child;
+    child = currentNode.nextnextElementSibling
+  ) {
+    if (hasFocusStyling(focusableNode, child)) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
+/**
+ * A rule that determines if a focusable accessible object has appropriate focus
+ * styling.
+ *
+ * @param  {nsIAccessible} accessible
+ *         Accessible to be checked for being focusable and having focus
+ *         styling.
+ *
+ * @return {null|Object}
+ *         Null if accessible has keyboard focus styling, audit report object
+ *         otherwise.
+ */
+function focusStyleRule(accessible) {
+  const { DOMNode } = accessible;
+  if (isInvalidNode(DOMNode)) {
+    return null;
+  }
+
+  // Ignore non-focusable elements.
+  if (!isKeyboardFocusable(accessible)) {
+    return null;
+  }
+
+  if (hasFocusStyling(DOMNode, DOMNode)) {
+    return null;
+  }
+
+  // If no browser or author focus styling was found, check if the node is a
+  // widget that is themed by platform native theme.
+  if (InspectorUtils.isElementThemed(DOMNode)) {
+    return null;
+  }
+
+  return { score: WARNING, issue: NO_FOCUS_VISIBLE };
+}
+
+/**
+ * A rule that determines if an interactive accessible has any associated
+ * accessible actions with it. If the element is interactive but and has no
+ * actions, assistive technology users will not be able to interact with it.
+ *
+ * @param  {nsIAccessible} accessible
+ *         Accessible to be checked for being interactive and having accessible
+ *         actions.
+ *
+ * @return {null|Object}
+ *         Null if accessible is not interactive or if it is and it has
+ *         accessible action associated with it, audit report object otherwise.
+ */
+function interactiveRule(accessible) {
+  if (!INTERACTIVE_ROLES.has(accessible.role)) {
+    return null;
+  }
+
+  if (accessible.actionCount > 0) {
+    return null;
+  }
+
+  return { score: FAIL, issue: INTERACTIVE_NO_ACTION };
+}
+
+/**
+ * A rule that determines if an interactive accessible is also focusable when
+ * not disabled.
+ *
+ * @param  {nsIAccessible} accessible
+ *         Accessible to be checked for being interactive and being focusable
+ *         when enabled.
+ *
+ * @return {null|Object}
+ *         Null if accessible is not interactive or if it is and it is focusable
+ *         when enabled, audit report object otherwise.
+ */
+function focusableRule(accessible) {
+  if (!KEYBOARD_FOCUSABLE_ROLES.has(accessible.role)) {
+    return null;
+  }
+
+  const state = {};
+  accessible.getState(state, {});
+  // We only expect in interactive accessible object to be focusable if it is
+  // not disabled.
+  if (state.value & Ci.nsIAccessibleStates.STATE_UNAVAILABLE) {
+    return null;
+  }
+
+  if (isKeyboardFocusable(accessible)) {
+    return null;
+  }
+
+  const ariaRoles = getAriaRoles(accessible);
+  if (
+    ariaRoles &&
+    (ariaRoles.includes("combobox") || ariaRoles.includes("listbox"))
+  ) {
+    // Do not force ARIA combobox or listbox to be focusable.
+    return null;
+  }
+
+  return { score: FAIL, issue: INTERACTIVE_NOT_FOCUSABLE };
+}
+
+/**
+ * A rule that determines if a focusable accessible has an associated
+ * interactive role.
+ *
+ * @param  {nsIAccessible} accessible
+ *         Accessible to be checked for having an interactive role if it is
+ *         focusable.
+ *
+ * @return {null|Object}
+ *         Null if accessible is not interactive or if it is and it has an
+ *         interactive role, audit report object otherwise.
+ */
+function semanticsRule(accessible) {
+  if (
+    INTERACTIVE_ROLES.has(accessible.role) ||
+    // Visible listboxes will have focusable state when inside comboboxes.
+    accessible.role === Ci.nsIAccessibleRole.ROLE_COMBOBOX_LIST
+  ) {
+    return null;
+  }
+
+  if (isKeyboardFocusable(accessible)) {
+    if (INTERACTIVE_IF_FOCUSABLE_ROLES.has(accessible.role)) {
+      return null;
+    }
+
+    // ROLE_TABLE is used for grids too which are considered interactive.
+    if (accessible.role === Ci.nsIAccessibleRole.ROLE_TABLE) {
+      const ariaRoles = getAriaRoles(accessible);
+      if (ariaRoles && ariaRoles.includes("grid")) {
+        return null;
+      }
+    }
+
+    return { score: WARNING, issue: FOCUSABLE_NO_SEMANTICS };
+  }
+
+  const state = {};
+  accessible.getState(state, {});
+  if (
+    // Ignore text leafs.
+    accessible.role === Ci.nsIAccessibleRole.ROLE_TEXT_LEAF ||
+    // Ignore accessibles with no accessible actions.
+    accessible.actionCount === 0 ||
+    // Ignore labels that have a label for relation with their target because
+    // they are clickable.
+    (accessible.role === Ci.nsIAccessibleRole.ROLE_LABEL &&
+      accessible.getRelationByType(Ci.nsIAccessibleRelation.RELATION_LABEL_FOR)
+        .targetsCount > 0) ||
+    // Ignore images that are inside an anchor (have linked state).
+    (accessible.role === Ci.nsIAccessibleRole.ROLE_GRAPHIC &&
+      state.value & Ci.nsIAccessibleStates.STATE_LINKED)
+  ) {
+    return null;
+  }
+
+  // Ignore anything but a click action in the list of actions.
+  for (let i = 0; i < accessible.actionCount; i++) {
+    if (accessible.getActionName(i) === CLICK_ACTION) {
+      return { score: FAIL, issue: MOUSE_INTERACTIVE_ONLY };
+    }
+  }
+
+  return null;
+}
+
+/**
+ * A rule that determines if an element associated with a focusable accessible
+ * has a positive tabindex.
+ *
+ * @param  {nsIAccessible} accessible
+ *         Accessible to be checked for having an element with positive tabindex
+ *         attribute.
+ *
+ * @return {null|Object}
+ *         Null if accessible is not focusable or if it is and its element's
+ *         tabindex attribute is less than 1, audit report object otherwise.
+ */
+function tabIndexRule(accessible) {
+  const { DOMNode } = accessible;
+  if (isInvalidNode(DOMNode)) {
+    return null;
+  }
+
+  if (!isKeyboardFocusable(accessible)) {
+    return null;
+  }
+
+  if (DOMNode.tabIndex > 0) {
+    return { score: WARNING, issue: FOCUSABLE_POSITIVE_TABINDEX };
+  }
+
+  return null;
+}
+
+function auditKeyboard(accessible) {
+  if (isDefunct(accessible)) {
+    return null;
+  }
+  // Do not test anything on accessible objects for documents or frames.
+  if (
+    accessible.role === Ci.nsIAccessibleRole.ROLE_DOCUMENT ||
+    accessible.role === Ci.nsIAccessibleRole.ROLE_INTERNAL_FRAME
+  ) {
+    return null;
+  }
+
+  // Check if interactive accessible can be used by the assistive
+  // technology.
+  let issue = interactiveRule(accessible);
+  if (issue) {
+    return issue;
+  }
+
+  // Check if interactive accessible is also focusable when enabled.
+  issue = focusableRule(accessible);
+  if (issue) {
+    return issue;
+  }
+
+  // Check if accessible object has an element with a positive tabindex.
+  issue = tabIndexRule(accessible);
+  if (issue) {
+    return issue;
+  }
+
+  // Check if a focusable accessible has interactive semantics.
+  issue = semanticsRule(accessible);
+  if (issue) {
+    return issue;
+  }
+
+  // Check if focusable accessible has associated focus styling.
+  issue = focusStyleRule(accessible);
+  if (issue) {
+    return issue;
+  }
+
+  return issue;
+}
+
+module.exports.auditKeyboard = auditKeyboard;
diff --git a/devtools/server/actors/accessibility/audit/moz.build b/devtools/server/actors/accessibility/audit/moz.build
new file mode 100644
index 0000000000..01bd0af849
--- /dev/null
+++ b/devtools/server/actors/accessibility/audit/moz.build
@@ -0,0 +1,12 @@
+# 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/.
+
+DevToolsModules(
+    "contrast.js",
+    "keyboard.js",
+    "text-label.js",
+)
+
+with Files("**"):
+    BUG_COMPONENT = ("DevTools", "Accessibility Tools")
diff --git a/devtools/server/actors/accessibility/audit/text-label.js b/devtools/server/actors/accessibility/audit/text-label.js
new file mode 100644
index 0000000000..8570c5cce8
--- /dev/null
+++ b/devtools/server/actors/accessibility/audit/text-label.js
@@ -0,0 +1,438 @@
+/* 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";
+
+const {
+  accessibility: {
+    AUDIT_TYPE: { TEXT_LABEL },
+    ISSUE_TYPE,
+    SCORES: { BEST_PRACTICES, FAIL, WARNING },
+  },
+} = require("resource://devtools/shared/constants.js");
+
+const {
+  AREA_NO_NAME_FROM_ALT,
+  DIALOG_NO_NAME,
+  DOCUMENT_NO_TITLE,
+  EMBED_NO_NAME,
+  FIGURE_NO_NAME,
+  FORM_FIELDSET_NO_NAME,
+  FORM_FIELDSET_NO_NAME_FROM_LEGEND,
+  FORM_NO_NAME,
+  FORM_NO_VISIBLE_NAME,
+  FORM_OPTGROUP_NO_NAME_FROM_LABEL,
+  FRAME_NO_NAME,
+  HEADING_NO_CONTENT,
+  HEADING_NO_NAME,
+  IFRAME_NO_NAME_FROM_TITLE,
+  IMAGE_NO_NAME,
+  INTERACTIVE_NO_NAME,
+  MATHML_GLYPH_NO_NAME,
+  TOOLBAR_NO_NAME,
+} = ISSUE_TYPE[TEXT_LABEL];
+
+/**
+ * Check if the accessible is visible to the assistive technology.
+ * @param {nsIAccessible} accessible
+ *        Accessible object to be tested for visibility.
+ *
+ * @returns {Boolean}
+ *         True if accessible object is visible to assistive technology.
+ */
+function isVisible(accessible) {
+  const state = {};
+  accessible.getState(state, {});
+  return !(state.value & Ci.nsIAccessibleStates.STATE_INVISIBLE);
+}
+
+/**
+ * Get related accessible objects that are targets of labelled by relation e.g.
+ * labels.
+ * @param {nsIAccessible} accessible
+ *        Accessible objects to get labels for.
+ *
+ * @returns {Array}
+ *          A list of accessible objects that are labels for a given accessible.
+ */
+function getLabels(accessible) {
+  const relation = accessible.getRelationByType(
+    Ci.nsIAccessibleRelation.RELATION_LABELLED_BY
+  );
+  return [...relation.getTargets().enumerate(Ci.nsIAccessible)];
+}
+
+/**
+ * Get a trimmed name of the accessible object.
+ *
+ * @param {nsIAccessible} accessible
+ *        Accessible objects to get a name for.
+ *
+ * @returns {null|String}
+ *          Trimmed name of the accessible object if available.
+ */
+function getAccessibleName(accessible) {
+  return accessible.name && accessible.name.trim();
+}
+
+/**
+ * A text label rule for accessible objects that must have a non empty
+ * accessible name.
+ *
+ * @returns {null|Object}
+ *          Failure audit report if accessible object has no or empty name, null
+ *          otherwise.
+ */
+const mustHaveNonEmptyNameRule = function (issue, accessible) {
+  const name = getAccessibleName(accessible);
+  return name ? null : { score: FAIL, issue };
+};
+
+/**
+ * A text label rule for accessible objects that should have a non empty
+ * accessible name as a best practice.
+ *
+ * @returns {null|Object}
+ *          Best practices audit report if accessible object has no or empty
+ *          name, null otherwise.
+ */
+const shouldHaveNonEmptyNameRule = function (issue, accessible) {
+  const name = getAccessibleName(accessible);
+  return name ? null : { score: BEST_PRACTICES, issue };
+};
+
+/**
+ * A text label rule for accessible objects that can be activated via user
+ * action and must have a non-empty name.
+ *
+ * @returns {null|Object}
+ *          Failure audit report if interactive accessible object has no or
+ *          empty name, null otherwise.
+ */
+const interactiveRule = mustHaveNonEmptyNameRule.bind(
+  null,
+  INTERACTIVE_NO_NAME
+);
+
+/**
+ * A text label rule for accessible objects that correspond to dialogs and thus
+ * should have a non-empty name.
+ *
+ * @returns {null|Object}
+ *          Best practices audit report if dialog accessible object has no or
+ *          empty name, null otherwise.
+ */
+const dialogRule = shouldHaveNonEmptyNameRule.bind(null, DIALOG_NO_NAME);
+
+/**
+ * A text label rule for accessible objects that provide visual information
+ * (images, canvas, etc.) and must have a defined name (that can be empty, e.g.
+ * "").
+ *
+ * @returns {null|Object}
+ *          Failure audit report if interactive accessible object has no name,
+ *          null otherwise.
+ */
+const imageRule = function (accessible) {
+  const name = getAccessibleName(accessible);
+  return name != null ? null : { score: FAIL, issue: IMAGE_NO_NAME };
+};
+
+/**
+ * A text label rule for accessible objects that correspond to form elements.
+ * These objects must have a non-empty name and must have a visible label.
+ *
+ * @returns {null|Object}
+ *          Failure audit report if form element accessible object has no name,
+ *          warning if the name does not come from a visible label, null
+ *          otherwise.
+ */
+const formRule = function (accessible) {
+  const name = getAccessibleName(accessible);
+  if (!name) {
+    return { score: FAIL, issue: FORM_NO_NAME };
+  }
+
+  const labels = getLabels(accessible);
+  const hasNameFromVisibleLabel = labels.some(label => isVisible(label));
+
+  return hasNameFromVisibleLabel
+    ? null
+    : { score: WARNING, issue: FORM_NO_VISIBLE_NAME };
+};
+
+/**
+ * A text label rule for elements that map to ROLE_GROUPING:
+ * * <OPTGROUP> must have a non-empty name and must be provided via the
+ *   "label" attribute.
+ * * <FIELDSET> must have a non-empty name and must be provided via the
+ *   corresponding <LEGEND> element.
+ *
+ * @returns {null|Object}
+ *          Failure audit report if form grouping accessible object has no name,
+ *          or has a name that is not derived from a required location, null
+ *          otherwise.
+ */
+const formGroupingRule = function (accessible) {
+  const name = getAccessibleName(accessible);
+  const { DOMNode } = accessible;
+
+  switch (DOMNode.nodeName) {
+    case "OPTGROUP":
+      return name && DOMNode.label && DOMNode.label.trim() === name
+        ? null
+        : {
+            score: FAIL,
+            issue: FORM_OPTGROUP_NO_NAME_FROM_LABEL,
+          };
+    case "FIELDSET":
+      if (!name) {
+        return { score: FAIL, issue: FORM_FIELDSET_NO_NAME };
+      }
+
+      const labels = getLabels(accessible);
+      const hasNameFromLegend = labels.some(
+        label =>
+          label.DOMNode.nodeName === "LEGEND" &&
+          label.name &&
+          label.name.trim() === name &&
+          isVisible(label)
+      );
+
+      return hasNameFromLegend
+        ? null
+        : {
+            score: WARNING,
+            issue: FORM_FIELDSET_NO_NAME_FROM_LEGEND,
+          };
+    default:
+      return null;
+  }
+};
+
+/**
+ * A text label rule for elements that map to ROLE_TEXT_CONTAINER:
+ * * <METER> mapps to ROLE_TEXT_CONTAINER and must have a name provided via
+ *   the visible label. Note: Will only work when bug 559770 is resolved (right
+ *   now, unlabelled meters are not mapped to an accessible object).
+ *
+ * @returns {null|Object}
+ *          Failure audit report depending on requirements for dialogs or form
+ *          meter element, null otherwise.
+ */
+const textContainerRule = function (accessible) {
+  const { DOMNode } = accessible;
+
+  switch (DOMNode.nodeName) {
+    case "DIALOG":
+      return dialogRule(accessible);
+    case "METER":
+      return formRule(accessible);
+    default:
+      return null;
+  }
+};
+
+/**
+ * A text label rule for elements that map to ROLE_INTERNAL_FRAME:
+ *  * <OBJECT> maps to ROLE_INTERNAL_FRAME. Check the type attribute and whether
+ *    it includes "image/" (e.g. image/jpeg, image/png, image/gif). If so, audit
+ *    it the same way other image roles are audited.
+ *  * <EMBED> maps to ROLE_INTERNAL_FRAME and must have a non-empty name.
+ *  * <FRAME> and <IFRAME> map to ROLE_INTERNAL_FRAME and must have a non-empty
+ *    title attribute.
+ *
+ * @returns {null|Object}
+ *          Failure audit report if the internal frame accessible object name is
+ *          not provided or if it is not derived from a required location, null
+ *          otherwise.
+ */
+const internalFrameRule = function (accessible) {
+  const { DOMNode } = accessible;
+  switch (DOMNode.nodeName) {
+    case "FRAME":
+      return mustHaveNonEmptyNameRule(FRAME_NO_NAME, accessible);
+    case "IFRAME":
+      const name = getAccessibleName(accessible);
+      const title = DOMNode.title && DOMNode.title.trim();
+
+      return title && title === name
+        ? null
+        : { score: FAIL, issue: IFRAME_NO_NAME_FROM_TITLE };
+    case "OBJECT": {
+      const type = DOMNode.getAttribute("type");
+      if (!type || !type.startsWith("image/")) {
+        return null;
+      }
+
+      return imageRule(accessible);
+    }
+    case "EMBED": {
+      const type = DOMNode.getAttribute("type");
+      if (!type || !type.startsWith("image/")) {
+        return mustHaveNonEmptyNameRule(EMBED_NO_NAME, accessible);
+      }
+      return imageRule(accessible);
+    }
+    default:
+      return null;
+  }
+};
+
+/**
+ * A text label rule for accessible objects that represent documents and should
+ * have title element provided.
+ *
+ * @returns {null|Object}
+ *          Failure audit report if document accessible object has no or empty
+ *          title, null otherwise.
+ */
+const documentRule = function (accessible) {
+  const title = accessible.DOMNode.title && accessible.DOMNode.title.trim();
+  return title ? null : { score: FAIL, issue: DOCUMENT_NO_TITLE };
+};
+
+/**
+ * A text label rule for accessible objects that correspond to headings and thus
+ * must be non-empty.
+ *
+ * @returns {null|Object}
+ *          Failure audit report if heading accessible object has no or
+ *          empty name or if its text content is empty, null otherwise.
+ */
+const headingRule = function (accessible) {
+  const name = getAccessibleName(accessible);
+  if (!name) {
+    return { score: FAIL, issue: HEADING_NO_NAME };
+  }
+
+  const content =
+    accessible.DOMNode.textContent && accessible.DOMNode.textContent.trim();
+  return content ? null : { score: WARNING, issue: HEADING_NO_CONTENT };
+};
+
+/**
+ * A text label rule for accessible objects that represent toolbars and must
+ * have a non-empty name if there is more than one toolbar present.
+ *
+ * @returns {null|Object}
+ *          Failure audit report if toolbar accessible object is not the only
+ *          toolbar in the document and has no or empty title, null otherwise.
+ */
+const toolbarRule = function (accessible) {
+  const toolbars =
+    accessible.DOMNode.ownerDocument.querySelectorAll(`[role="toolbar"]`);
+
+  return toolbars.length > 1
+    ? mustHaveNonEmptyNameRule(TOOLBAR_NO_NAME, accessible)
+    : null;
+};
+
+/**
+ * A text label rule for accessible objects that represent link (anchors, areas)
+ * and must have a non-empty name.
+ *
+ * @returns {null|Object}
+ *          Failure audit report if link accessible object has no or empty name,
+ *          or in case when it's an <area> element with href attribute the name
+ *          is not specified by an alt attribute, null otherwise.
+ */
+const linkRule = function (accessible) {
+  const { DOMNode } = accessible;
+  if (DOMNode.nodeName === "AREA" && DOMNode.hasAttribute("href")) {
+    const alt = DOMNode.getAttribute("alt");
+    const name = getAccessibleName(accessible);
+    return alt && alt.trim() === name
+      ? null
+      : { score: FAIL, issue: AREA_NO_NAME_FROM_ALT };
+  }
+
+  return interactiveRule(accessible);
+};
+
+/**
+ * A text label rule for accessible objects that are used to display
+ * non-standard symbols where existing Unicode characters are not available and
+ * must have a non-empty name.
+ *
+ * @returns {null|Object}
+ *          Failure audit report if mglyph accessible object has no or empty
+ *          name, and no or empty alt attribute, null otherwise.
+ */
+const mathmlGlyphRule = function (accessible) {
+  const name = getAccessibleName(accessible);
+  if (name) {
+    return null;
+  }
+
+  const { DOMNode } = accessible;
+  const alt = DOMNode.getAttribute("alt");
+  return alt && alt.trim()
+    ? null
+    : { score: FAIL, issue: MATHML_GLYPH_NO_NAME };
+};
+
+const RULES = {
+  [Ci.nsIAccessibleRole.ROLE_BUTTONMENU]: interactiveRule,
+  [Ci.nsIAccessibleRole.ROLE_CANVAS]: imageRule,
+  [Ci.nsIAccessibleRole.ROLE_CHECKBUTTON]: formRule,
+  [Ci.nsIAccessibleRole.ROLE_CHECK_MENU_ITEM]: interactiveRule,
+  [Ci.nsIAccessibleRole.ROLE_CHECK_RICH_OPTION]: formRule,
+  [Ci.nsIAccessibleRole.ROLE_COLUMNHEADER]: interactiveRule,
+  [Ci.nsIAccessibleRole.ROLE_COMBOBOX]: formRule,
+  [Ci.nsIAccessibleRole.ROLE_COMBOBOX_OPTION]: interactiveRule,
+  [Ci.nsIAccessibleRole.ROLE_DIAGRAM]: imageRule,
+  [Ci.nsIAccessibleRole.ROLE_DIALOG]: dialogRule,
+  [Ci.nsIAccessibleRole.ROLE_DOCUMENT]: documentRule,
+  [Ci.nsIAccessibleRole.ROLE_EDITCOMBOBOX]: formRule,
+  [Ci.nsIAccessibleRole.ROLE_ENTRY]: formRule,
+  [Ci.nsIAccessibleRole.ROLE_FIGURE]: shouldHaveNonEmptyNameRule.bind(
+    null,
+    FIGURE_NO_NAME
+  ),
+  [Ci.nsIAccessibleRole.ROLE_GRAPHIC]: imageRule,
+  [Ci.nsIAccessibleRole.ROLE_GROUPING]: formGroupingRule,
+  [Ci.nsIAccessibleRole.ROLE_HEADING]: headingRule,
+  [Ci.nsIAccessibleRole.ROLE_IMAGE_MAP]: imageRule,
+  [Ci.nsIAccessibleRole.ROLE_INTERNAL_FRAME]: internalFrameRule,
+  [Ci.nsIAccessibleRole.ROLE_LINK]: linkRule,
+  [Ci.nsIAccessibleRole.ROLE_LISTBOX]: formRule,
+  [Ci.nsIAccessibleRole.ROLE_MATHML_GLYPH]: mathmlGlyphRule,
+  [Ci.nsIAccessibleRole.ROLE_MENUITEM]: interactiveRule,
+  [Ci.nsIAccessibleRole.ROLE_OPTION]: interactiveRule,
+  [Ci.nsIAccessibleRole.ROLE_OUTLINEITEM]: interactiveRule,
+  [Ci.nsIAccessibleRole.ROLE_PAGETAB]: interactiveRule,
+  [Ci.nsIAccessibleRole.ROLE_PASSWORD_TEXT]: formRule,
+  [Ci.nsIAccessibleRole.ROLE_PROGRESSBAR]: formRule,
+  [Ci.nsIAccessibleRole.ROLE_PUSHBUTTON]: interactiveRule,
+  [Ci.nsIAccessibleRole.ROLE_RADIOBUTTON]: formRule,
+  [Ci.nsIAccessibleRole.ROLE_RADIO_MENU_ITEM]: interactiveRule,
+  [Ci.nsIAccessibleRole.ROLE_ROWHEADER]: interactiveRule,
+  [Ci.nsIAccessibleRole.ROLE_SLIDER]: formRule,
+  [Ci.nsIAccessibleRole.ROLE_SPINBUTTON]: formRule,
+  [Ci.nsIAccessibleRole.ROLE_SWITCH]: formRule,
+  [Ci.nsIAccessibleRole.ROLE_TEXT_CONTAINER]: textContainerRule,
+  [Ci.nsIAccessibleRole.ROLE_TOGGLE_BUTTON]: interactiveRule,
+  [Ci.nsIAccessibleRole.ROLE_TOOLBAR]: toolbarRule,
+};
+
+/**
+ * Perform audit for WCAG 1.1 criteria related to providing alternative text
+ * depending on the type of content.
+ * @param {nsIAccessible} accessible
+ *        Accessible object to be tested to determine if it requires and has
+ *        an appropriate text alternative.
+ *
+ * @return {null|Object}
+ *         Null if accessible does not need or has the right text alternative,
+ *         audit data otherwise. This data is used in the accessibility panel
+ *         for its audit filters, audit badges, sidebar checks section and
+ *         highlighter.
+ */
+function auditTextLabel(accessible) {
+  const rule = RULES[accessible.role];
+  return rule ? rule(accessible) : null;
+}
+
+module.exports.auditTextLabel = auditTextLabel;