Bug 1790435: Don't apply rotor post-filter if AXSearchText is empty r=eeejay

Differential Revision: https://phabricator.services.mozilla.com/D160836

accessible/mac/MOXSearchInfo.mm

@@ -123,7 +123,9 @@ using namespace mozilla::a11y;
 
 - (BOOL)shouldApplyPostFilter {
   // We currently only support AXSearchText as a post-search filter.
-  return !!mSearchText;
+  // In some cases, VO passes a non-null, empty string for AXSearchText.
+  // In that case, we should act as if no AXSearchText was given.
+  return !!mSearchText && [mSearchText length] > 0;
 }
 
 - (NSArray<mozAccessible*>*)applyPostFilter:(NSArray<mozAccessible*>*)matches {

accessible/tests/browser/mac/browser_rotor.js

@@ -58,6 +58,54 @@ addAccessibleTask(
   }
 );
 
+/**
+ * Test rotor with heading and empty search text
+ */
+addAccessibleTask(
+  `<h1 id="hello">hello</h1><br><h2 id="world">world</h2><br>goodbye`,
+  async (browser, accDoc) => {
+    const searchPred = {
+      AXSearchKey: "AXHeadingSearchKey",
+      AXImmediateDescendantsOnly: 1,
+      AXResultsLimit: -1,
+      AXDirection: "AXDirectionNext",
+      AXSearchText: "",
+    };
+
+    const webArea = accDoc.nativeInterface.QueryInterface(
+      Ci.nsIAccessibleMacInterface
+    );
+    is(
+      webArea.getAttributeValue("AXRole"),
+      "AXWebArea",
+      "Got web area accessible"
+    );
+
+    const headingCount = webArea.getParameterizedAttributeValue(
+      "AXUIElementCountForSearchPredicate",
+      NSDictionary(searchPred)
+    );
+    is(headingCount, 2, "Found two headings");
+
+    const headings = webArea.getParameterizedAttributeValue(
+      "AXUIElementsForSearchPredicate",
+      NSDictionary(searchPred)
+    );
+    const hello = getNativeInterface(accDoc, "hello");
+    const world = getNativeInterface(accDoc, "world");
+    is(
+      headings[0].getAttributeValue("AXTitle"),
+      hello.getAttributeValue("AXTitle"),
+      "Found correct first heading"
+    );
+    is(
+      headings[1].getAttributeValue("AXTitle"),
+      world.getAttributeValue("AXTitle"),
+      "Found correct second heading"
+    );
+  }
+);
+
 /**
  * Test rotor with articles
  */