Bug 1568360 - Don't calculate the accessible names for table or grid rows unless they have an explicit ARIA role, r=Jamie

Previously, we would always calculate the name for tr elements from their descendants unconditionally. Assistive technologies aren't using this information, moreover, it causes problems if the name gets too long, for example in layout tables.

We now only calculate the name if the tr element has an explicit ARIA role.

Differential Revision: https://phabricator.services.mozilla.com/D39314

--HG--
extra : moz-landing-system : lando

accessible/generic/ARIAGridAccessible.cpp

@@ -472,6 +472,19 @@ GroupPos ARIARowAccessible::GroupPosition() {
   return AccessibleWrap::GroupPosition();
 }
 
+// Accessible protected
+ENameValueFlag ARIARowAccessible::NativeName(nsString& aName) const {
+  // We want to calculate the name from content only if an ARIA role is
+  // present. ARIARowAccessible might also be used by tables with
+  // display:block; styling, in which case we do not want the name from
+  // content.
+  if (HasStrongARIARole()) {
+    return AccessibleWrap::NativeName(aName);
+  }
+
+  return eNameOK;
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // ARIAGridCellAccessible
 ////////////////////////////////////////////////////////////////////////////////

accessible/generic/ARIAGridAccessible.h

@@ -81,6 +81,9 @@ class ARIARowAccessible : public HyperTextAccessibleWrap {
 
  protected:
   virtual ~ARIARowAccessible() {}
+
+  // Accessible
+  virtual ENameValueFlag NativeName(nsString& aName) const override;
 };
 
 /**

accessible/html/HTMLTableAccessible.cpp

@@ -328,6 +328,17 @@ GroupPos HTMLTableRowAccessible::GroupPosition() {
   return AccessibleWrap::GroupPosition();
 }
 
+// Accessible protected
+ENameValueFlag HTMLTableRowAccessible::NativeName(nsString& aName) const {
+  // For table row accessibles, we only want to calculate the name from the
+  // sub tree if an ARIA role is present.
+  if (HasStrongARIARole()) {
+    return AccessibleWrap::NativeName(aName);
+  }
+
+  return eNameOK;
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // HTMLTableAccessible
 ////////////////////////////////////////////////////////////////////////////////

accessible/html/HTMLTableAccessible.h

@@ -99,6 +99,9 @@ class HTMLTableRowAccessible : public HyperTextAccessibleWrap {
 
  protected:
   virtual ~HTMLTableRowAccessible() {}
+
+  // Accessible
+  virtual ENameValueFlag NativeName(nsString& aName) const override;
 };
 
 /**

accessible/tests/mochitest/name/test_general.html

@@ -221,6 +221,19 @@
 
       testName("test_note", null);
 
+      // //////////////////////////////////////////////////////////////////////
+      // Tests for name from sub tree of tr element.
+
+      // By default, we want no name.
+      testName("NoNameForTR", null);
+      testName("NoNameForNonStandardTR", null);
+
+      // But we want it if the tr has an ARIA role.
+      testName("NameForTRBecauseStrongARIA", "a b");
+
+      // But not if it is a weak (landmark) ARIA role
+      testName("NoNameForTRBecauseWeakARIA", null);
+
       SimpleTest.finish();
     }
 
@@ -631,5 +644,19 @@
   <!-- duplicate announcement -->
   <div id="test_note" role="note">subtree</div>
 
+  <!-- No name for tr from its sub tree -->
+  <table><tr id="NoNameForTR"><th>a</th><td>b</td></tr></table>
+  <table style="display: block;">
+    <tr id="NoNameForNonStandardTR" style="display:block;">
+      <th>a</th><td>b</td>
+    </tr>
+  </table>
+
+  <!-- Name from sub tree of tr, because it has a strong ARIA role -->
+  <table><tr id="NameForTRBecauseStrongARIA" role="row"><th>a</th><td>b</td></tr></table>
+
+  <!-- No name for tr because of weak (landmark) role -->
+  <table><tr id="NoNameForTRBecauseWeakARIA" role="main"><th>a</th><td>b</td></tr></table>
+
 </body>
 </html>