feat: Autocomplete accessibility features (#5008)

* Accessible autocomplete

* remove ace_line_id and fix autocompletion tests

Author: aoyku

src/autocomplete.js

@@ -2,6 +2,7 @@
 
 var HashHandler = require("./keyboard/hash_handler").HashHandler;
 var AcePopup = require("./autocomplete/popup").AcePopup;
+var getAriaId = require("./autocomplete/popup").getAriaId;
 var util = require("./autocomplete/util");
 var lang = require("./lib/lang");
 var dom = require("./lib/dom");
@@ -54,6 +55,7 @@ var Autocomplete = function() {
         this.popup.autoSelect = this.autoSelect;
 
         this.popup.setData(this.completions.filtered, this.completions.filterText);
+        this.editor.textInput.setAriaOptions({activeDescendant: getAriaId(this.popup.getRow())});
 
         editor.keyBinding.addKeyboardHandler(this.keyboardHandler);
 

src/autocomplete/popup.js

@@ -7,6 +7,10 @@ var event = require("../lib/event");
 var lang = require("../lib/lang");
 var dom = require("../lib/dom");
 
+var getAriaId = function(index) {
+    return `suggest-aria-id:${index}`;
+};
+
 var $singleLineEditor = function(el) {
     var renderer = new Renderer(el);
 
@@ -45,6 +49,10 @@ var AcePopup = function(parentNode) {
     popup.renderer.content.style.cursor = "default";
     popup.renderer.setStyle("ace_autocomplete");
 
+    // Set aria attributes for the popup
+    popup.renderer.container.setAttribute("role", "listbox");
+    popup.renderer.container.setAttribute("aria-label", "Autocomplete suggestions");
+
     popup.setOption("displayIndentGuides", false);
     popup.setOption("dragDelay", 150);
 
@@ -114,11 +122,21 @@ var AcePopup = function(parentNode) {
         var row = popup.getRow();
         var t = popup.renderer.$textLayer;
         var selected = t.element.childNodes[row - t.config.firstRow];
-        if (selected !== t.selectedNode && t.selectedNode)
+        var el = document.activeElement; // Active element is textarea of main editor
+        if (selected !== t.selectedNode && t.selectedNode) {
             dom.removeCssClass(t.selectedNode, "ace_selected");
+            el.removeAttribute("aria-activedescendant");
+            t.selectedNode.removeAttribute("id");
+        }
         t.selectedNode = selected;
-        if (selected)
+        if (selected) {
             dom.addCssClass(selected, "ace_selected");
+            var ariaId = getAriaId(row);
+            selected.id = ariaId;
+            popup.renderer.container.setAttribute("aria-activedescendant", ariaId);
+            el.setAttribute("aria-activedescendant", ariaId);
+            selected.setAttribute("aria-label", popup.getData(row).value);
+        }
     });
     var hideHoverMarker = function() { setHoverMarker(-1); };
     var setHoverMarker = function(row, suppressRedraw) {
@@ -350,3 +368,4 @@ dom.importCssString(`
 
 exports.AcePopup = AcePopup;
 exports.$singleLineEditor = $singleLineEditor;
+exports.getAriaId = getAriaId;

src/autocomplete_test.js

@@ -26,16 +26,16 @@ module.exports = {
         editor.renderer.$themeId = "./theme/textmate";
 
         editor.execCommand("insertstring", "a");
-        checkInnerHTML('<d "ace_line ace_selected"><s "ace_completion-highlight">a</s><s "ace_">rraysort</s><s "ace_completion-meta">local</s></d><d "ace_line"><s "ace_completion-highlight">a</s><s "ace_">looooooooooooooooooooooooooooong_word</s><s "ace_completion-meta">local</s></d>', function() {
+        checkInnerHTML('<d "ace_line ace_selected" role="option" id="suggest-aria-id:0" aria-label="arraysort"><s "ace_completion-highlight">a</s><s "ace_">rraysort</s><s "ace_completion-meta">local</s></d><d "ace_line" role="option"><s "ace_completion-highlight">a</s><s "ace_">looooooooooooooooooooooooooooong_word</s><s "ace_completion-meta">local</s></d>', function() {
             editor.execCommand("insertstring", "rr");
-            checkInnerHTML('<d "ace_line ace_selected"><s "ace_completion-highlight">arr</s><s "ace_">aysort</s><s "ace_completion-meta">local</s></d>', function() {
+            checkInnerHTML('<d "ace_line ace_selected" role="option" id="suggest-aria-id:0" aria-label="arraysort"><s "ace_completion-highlight">arr</s><s "ace_">aysort</s><s "ace_completion-meta">local</s></d>', function() {
                 editor.execCommand("insertstring", "r");
-                checkInnerHTML('<d "ace_line ace_selected"><s "ace_completion-highlight">arr</s><s "ace_">ayso</s><s "ace_completion-highlight">r</s><s "ace_">t</s><s "ace_completion-meta">local</s></d>', function() {
+                checkInnerHTML('<d "ace_line ace_selected" role="option" id="suggest-aria-id:0" aria-label="arraysort"><s "ace_completion-highlight">arr</s><s "ace_">ayso</s><s "ace_completion-highlight">r</s><s "ace_">t</s><s "ace_completion-meta">local</s></d>', function() {
 
                     editor.onCommandKey(null, 0, 13);
                     assert.equal(editor.getValue(), "arraysort\narraysort alooooooooooooooooooooooooooooong_word");
                     editor.execCommand("insertstring", " looooooooooooooooooooooooooooong_");
-                    checkInnerHTML('<d "ace_line ace_selected"><s "ace_">a</s><s "ace_completion-highlight">looooooooooooooooooooooooooooong_</s><s "ace_">word</s><s "ace_completion-meta">local</s></d>', function() {
+                    checkInnerHTML('<d "ace_line ace_selected" role="option" id="suggest-aria-id:0" aria-label="alooooooooooooooooooooooooooooong_word"><s "ace_">a</s><s "ace_completion-highlight">looooooooooooooooooooooooooooong_</s><s "ace_">word</s><s "ace_completion-meta">local</s></d>', function() {
                         editor.onCommandKey(null, 0, 13);
                         editor.destroy();
                         editor.container.remove();

src/keyboard/textinput.js

@@ -48,7 +48,23 @@ var TextInput = function(parentNode, host) {
     // FOCUS
     // ie9 throws error if document.activeElement is accessed too soon
     try { var isFocused = document.activeElement === text; } catch(e) {}
-    
+
+    this.setAriaOptions = function(options) {
+        if (options.activeDescendant) {
+            text.setAttribute("aria-haspopup", "true");
+            text.setAttribute("aria-autocomplete", "list");
+            text.setAttribute("aria-activedescendant", options.activeDescendant);
+        } else {
+            text.setAttribute("aria-haspopup", "false");
+            text.setAttribute("aria-autocomplete", "both");
+            text.removeAttribute("aria-activedescendant");
+        }
+        if (options.role) {
+            text.setAttribute("role", options.role);
+        }
+    };
+    this.setAriaOptions({role: "textbox"});
+
     event.addListener(text, "blur", function(e) {
         if (ignoreFocusEvents) return;
         host.onBlur(e);

src/layer/text.js

@@ -293,6 +293,7 @@ var Text = function(parentEl) {
                 lineEl.className = "ace_line_group";
             } else {
                 lineEl.className = "ace_line";
+                lineEl.setAttribute("role", "option");
             }
             fragment.push(line);