respond to code review and fix tests

tests were failing for a couple of reasons:
(1) I was setting aria-hidden to "false" instead of not having the attribute
(2) tabindex was being set as tabindex=0 instead of now, with js, setting it to tabindex="0" (equivalent, but the getter reflects the difference)

fix the former by changing the behavior and the latter by updating the test expectation

src/controller.ts

@@ -97,6 +97,7 @@ class ControllerBase {
   }
   setAriaLabel(ariaLabel: string) {
     var oldAriaLabel = this.getAriaLabel();
+    if (ariaLabel === oldAriaLabel) return this;
     if (ariaLabel && typeof ariaLabel === 'string' && ariaLabel !== '') {
       this.ariaLabel = ariaLabel;
     } else if (this.editable) {

src/publicapi.ts

@@ -304,7 +304,6 @@ function getInterface(v: number): MathQuill.v3.API | MathQuill.v1.API {
     }
 
     setAriaLabel(ariaLabel: string) {
-      if (ariaLabel === this.__controller.getAriaLabel()) return this;
       this.__controller.setAriaLabel(ariaLabel);
       return this;
     }

src/services/textarea.ts

@@ -65,6 +65,13 @@ class Controller extends Controller_scrollHoriz {
         ? this.options.tabbable
         : this.KIND_OF_MQ !== 'StaticMath';
 
+    if (!this.options.tabbable && this.KIND_OF_MQ === 'StaticMath') {
+      // aria-hide noninteractive textarea element for static math
+      textarea.setAttribute('aria-hidden', 'true');
+    }
+    if (tabbable && this.mathspeakSpan) {
+      this.mathspeakSpan.setAttribute('aria-hidden', 'true');
+    }
     this.setTabbable(tabbable);
   }
 
@@ -73,8 +80,18 @@ class Controller extends Controller_scrollHoriz {
     this.wasTabbable = tabbable;
 
     this.textarea?.setAttribute('tabindex', tabbable ? '0' : '-1');
-    this.textarea?.setAttribute('aria-hidden', !this.options.tabbable && this.KIND_OF_MQ === 'StaticMath' ? 'true' : 'false');
-    this.mathspeakSpan?.setAttribute('aria-hidden', tabbable ? 'true' : 'false');
+
+    if (!tabbable && this.KIND_OF_MQ === 'StaticMath') {
+      this.textarea?.setAttribute('aria-hidden', 'true');
+    } else {
+      this.textarea?.removeAttribute('aria-hidden');
+    }
+
+    if (tabbable) {
+      this.mathspeakSpan?.setAttribute('aria-hidden', 'true');
+    } else {
+      this.mathspeakSpan?.removeAttribute('aria-hidden');
+    }
   }
 
   selectionChanged() {

test/unit/focusBlur.test.js

@@ -118,7 +118,7 @@ suite('focusBlur', function () {
       'full textarea selected'
     );
 
-    assert.equal($(document.activeElement).attr('tabindex'), 0);
+    assert.equal($(document.activeElement).attr('tabindex'), '0');
 
     mq.blur();
     assertHasFocus(mq, 'math field', 'not');