Bug 1625266: Add stepper subclass, support value changes. r=eeejay

Differential Revision: https://phabricator.services.mozilla.com/D70772

accessible/mac/AccessibleWrap.mm

@@ -182,9 +182,7 @@ Class a11y::GetTypeFromRole(roles::Role aRole) {
   switch (aRole) {
     case roles::COMBOBOX:
     case roles::PUSHBUTTON:
-    case roles::SPLITBUTTON: {
       return [mozButtonAccessible class];
-    }
 
     case roles::PAGETAB:
       return [mozTabAccessible class];
@@ -194,8 +192,9 @@ Class a11y::GetTypeFromRole(roles::Role aRole) {
     case roles::RADIOBUTTON:
       return [mozCheckboxAccessible class];
 
+    case roles::SPINBUTTON:
     case roles::SLIDER:
-      return [mozSliderAccessible class];
+      return [mozIncrementableAccessible class];
 
     case roles::HEADING:
       return [mozHeadingAccessible class];

accessible/mac/mozActionElements.h

@@ -26,8 +26,8 @@
 @end
 
 /**
- * Accessible for a slider
+ * Base accessible for an incrementable
  */
-@interface mozSliderAccessible : mozAccessible
+@interface mozIncrementableAccessible : mozAccessible
 
 @end

accessible/mac/mozActionElements.mm

@@ -162,7 +162,7 @@ enum CheckboxValue {
 
 @end
 
-@implementation mozSliderAccessible
+@implementation mozIncrementableAccessible
 
 - (NSArray*)accessibilityActionNames {
   NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NIL;
@@ -207,12 +207,20 @@ enum CheckboxValue {
 
   if (AccessibleWrap* accWrap = [self getGeckoAccessible]) {
     double newVal = accWrap->CurValue() + (accWrap->Step() * factor);
-    if (newVal >= accWrap->MinValue() && newVal <= accWrap->MaxValue()) {
+    double min = accWrap->MinValue();
+    double max = accWrap->MaxValue();
+    if ((IsNaN(min) || newVal >= min) && (IsNaN(max) || newVal <= max)) {
       accWrap->SetCurValue(newVal);
     }
   } else if (ProxyAccessible* proxy = [self getProxyAccessible]) {
     double newVal = proxy->CurValue() + (proxy->Step() * factor);
-    if (newVal >= proxy->MinValue() && newVal <= proxy->MaxValue()) {
+    double min = proxy->MinValue();
+    double max = proxy->MaxValue();
+    // Because min and max are not required attributes, we first check
+    // if the value is undefined. If this check fails,
+    // the value is defined, and we we verify our new value falls
+    // within the bound (inclusive).
+    if ((IsNaN(min) || newVal >= min) && (IsNaN(max) || newVal <= max)) {
       proxy->SetCurValue(newVal);
     }
   }
@@ -222,6 +230,7 @@ enum CheckboxValue {
 
 - (void)handleAccessibleEvent:(uint32_t)eventType {
   switch (eventType) {
+    case nsIAccessibleEvent::EVENT_TEXT_VALUE_CHANGE:
     case nsIAccessibleEvent::EVENT_VALUE_CHANGE:
       [self postNotification:NSAccessibilityValueChangedNotification];
       break;

accessible/tests/browser/mac/browser_range.js

@@ -48,3 +48,45 @@ addAccessibleTask(
     );
   }
 );
+
+/**
+ * Test input[type=range]
+ */
+addAccessibleTask(
+  `<input type="number" value="11" id="number">`,
+  async (browser, accDoc) => {
+    let number = getNativeInterface(accDoc, "number");
+    is(
+      number.getAttributeValue("AXRole"),
+      "AXIncrementor",
+      "Correct AXIncrementor role"
+    );
+    is(number.getAttributeValue("AXValue"), 11, "Correct initial value");
+
+    let actions = number.actionNames;
+    ok(actions.includes("AXDecrement"), "Has decrement action");
+    ok(actions.includes("AXIncrement"), "Has increment action");
+
+    let evt = waitForMacEvent("AXValueChanged");
+    number.performAction("AXIncrement");
+    await evt;
+    is(number.getAttributeValue("AXValue"), 12, "Correct increment value");
+
+    evt = waitForMacEvent("AXValueChanged");
+    number.performAction("AXDecrement");
+    await evt;
+    is(number.getAttributeValue("AXValue"), 11, "Correct decrement value");
+
+    evt = waitForMacEvent("AXValueChanged");
+    // Adjust value via script in content
+    await SpecialPowers.spawn(browser, [], () => {
+      content.document.getElementById("number").value = 42;
+    });
+    await evt;
+    is(
+      number.getAttributeValue("AXValue"),
+      42,
+      "Correct value from content change"
+    );
+  }
+);