Bug 1633570 - Add setter for AXValue (incrementables only) r=morgan

This commit adds an AXValue setter to incremental accessibles, as well
as tests to validate that setter on both a range and number input.

Differential Revision: https://phabricator.services.mozilla.com/D106333

accessible/mac/mozActionElements.h

@@ -69,6 +69,9 @@
  */
 @interface mozIncrementableAccessible : mozAccessible
 
+// override
+- (void)moxSetValue:(id)value;
+
 // override
 - (void)moxPerformIncrement;
 

accessible/mac/mozActionElements.mm

@@ -153,6 +153,10 @@ enum CheckboxValue {
 
 @implementation mozIncrementableAccessible
 
+- (void)moxSetValue:(id)value {
+  [self setValue:([value doubleValue])];
+}
+
 - (void)moxPerformIncrement {
   [self changeValueBySteps:1];
 }
@@ -174,35 +178,52 @@ enum CheckboxValue {
 }
 
 /*
- * Updates the accessible's current value by (factor * step).
- * If incrementing factor should be positive, if decrementing
- * factor should be negative.
+ * Updates the accessible's current value by factor and step.
+ *
+ * factor: A signed integer representing the number of times to
+ *    apply step to the current value. A positive value will increment,
+ *    while a negative one will decrement.
+ * step: An unsigned integer specified by the webauthor and indicating the
+ *    amount by which to increment/decrement the current value.
  */
-
 - (void)changeValueBySteps:(int)factor {
-  NS_OBJC_BEGIN_TRY_IGNORE_BLOCK;
+  MOZ_ASSERT(!mGeckoAccessible.IsNull(), "mGeckoAccessible is null");
+
+  if (LocalAccessible* acc = mGeckoAccessible.AsAccessible()) {
+    double newValue = acc->CurValue() + (acc->Step() * factor);
+    [self setValue:(newValue)];
+  } else {
+    RemoteAccessible* proxy = mGeckoAccessible.AsProxy();
+    double newValue = proxy->CurValue() + (proxy->Step() * factor);
+    [self setValue:(newValue)];
+  }
+}
+
+/*
+ * Updates the accessible's current value to the specified value
+ */
+- (void)setValue:(double)value {
+  MOZ_ASSERT(!mGeckoAccessible.IsNull(), "mGeckoAccessible is null");
 
   if (LocalAccessible* acc = mGeckoAccessible.AsAccessible()) {
-    double newVal = acc->CurValue() + (acc->Step() * factor);
     double min = acc->MinValue();
     double max = acc->MaxValue();
-    if ((IsNaN(min) || newVal >= min) && (IsNaN(max) || newVal <= max)) {
-      acc->SetCurValue(newVal);
-    }
-  } else if (RemoteAccessible* proxy = mGeckoAccessible.AsProxy()) {
-    double newVal = proxy->CurValue() + (proxy->Step() * factor);
-    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
+    // the value is defined, and we verify our new value falls
     // within the bound (inclusive).
-    if ((IsNaN(min) || newVal >= min) && (IsNaN(max) || newVal <= max)) {
-      proxy->SetCurValue(newVal);
+    if ((IsNaN(min) || value >= min) && (IsNaN(max) || value <= max)) {
+      acc->SetCurValue(value);
+    }
+  } else {
+    RemoteAccessible* proxy = mGeckoAccessible.AsProxy();
+    double min = proxy->MinValue();
+    double max = proxy->MaxValue();
+    // As above, check if the value is within bounds.
+    if ((IsNaN(min) || value >= min) && (IsNaN(max) || value <= max)) {
+      proxy->SetCurValue(value);
     }
   }
-
-  NS_OBJC_END_TRY_IGNORE_BLOCK;
 }
 
 @end

accessible/tests/browser/mac/browser_range.js

@@ -12,6 +12,7 @@ loadScripts(
 );
 
 /**
+ * Verify that the value of a slider input can be incremented/decremented
  * Test input[type=range]
  */
 addAccessibleTask(
@@ -50,10 +51,32 @@ addAccessibleTask(
 );
 
 /**
+ * Verify that the value of a slider input can be set directly
  * Test input[type=range]
  */
 addAccessibleTask(
-  `<input type="number" value="11" id="number">`,
+  `<input id="range" type="range" min="1" max="100" value="1" step="10">`,
+  async (browser, accDoc) => {
+    let nextValue = "21";
+    let range = getNativeInterface(accDoc, "range");
+    is(range.getAttributeValue("AXRole"), "AXSlider", "Correct AXSlider role");
+    is(range.getAttributeValue("AXValue"), "1", "Correct initial value");
+
+    ok(range.isAttributeSettable("AXValue"), "Range AXValue is settable.");
+
+    let evt = waitForMacEvent("AXValueChanged");
+    range.setAttributeValue("AXValue", nextValue);
+    await evt;
+    is(range.getAttributeValue("AXValue"), nextValue, "Correct updated value");
+  }
+);
+
+/**
+ * Verify that the value of a number input can be incremented/decremented
+ * Test input[type=number]
+ */
+addAccessibleTask(
+  `<input type="number" value="11" id="number" step=".05">`,
   async (browser, accDoc) => {
     let number = getNativeInterface(accDoc, "number");
     is(
@@ -70,7 +93,7 @@ addAccessibleTask(
     let evt = waitForMacEvent("AXValueChanged");
     number.performAction("AXIncrement");
     await evt;
-    is(number.getAttributeValue("AXValue"), "12", "Correct increment value");
+    is(number.getAttributeValue("AXValue"), "11.05", "Correct increment value");
 
     evt = waitForMacEvent("AXValueChanged");
     number.performAction("AXDecrement");
@@ -90,3 +113,28 @@ addAccessibleTask(
     );
   }
 );
+
+/**
+ * Verify that the value of a number input can be set directly
+ * Test input[type=number]
+ */
+addAccessibleTask(
+  `<input type="number" value="11" id="number">`,
+  async (browser, accDoc) => {
+    let nextValue = "21";
+    let number = getNativeInterface(accDoc, "number");
+    is(
+      number.getAttributeValue("AXRole"),
+      "AXIncrementor",
+      "Correct AXIncrementor role"
+    );
+    is(number.getAttributeValue("AXValue"), "11", "Correct initial value");
+
+    ok(number.isAttributeSettable("AXValue"), "Range AXValue is settable.");
+
+    let evt = waitForMacEvent("AXValueChanged");
+    number.setAttributeValue("AXValue", nextValue);
+    await evt;
+    is(number.getAttributeValue("AXValue"), nextValue, "Correct updated value");
+  }
+);