Bug 1901465: Implement ITextRangeProvider::ScrollIntoView. r=nlapre

Differential Revision: https://phabricator.services.mozilla.com/D232178

accessible/tests/browser/windows/uia/browser_textPatterns.js

@@ -1856,3 +1856,55 @@ addUiaTask(
   },
   { uiaEnabled: true, uiaDisabled: true, chrome: true }
 );
+
+/**
+ * Test the TextRange pattern's ScrollIntoView method.
+ */
+addUiaTask(
+  `
+<style>
+  body {
+    margin: 0;
+  }
+</style>
+<p>p1</p>
+<hr style="height: 200vh;">
+<p id="p2">p2</p>
+<hr style="height: 200vh;">
+<p>p3</p>
+  `,
+  async function testTextRangeScrollIntoView(browser, docAcc) {
+    const [docLeft, docTop, , docBottom] = await runPython(`
+      global doc
+      doc = getDocUia()
+      rect = doc.CurrentBoundingRectangle
+      return (rect.left, rect.top, rect.right, rect.bottom)
+    `);
+
+    info("Scrolling p2 to top");
+    let scrolled = waitForEvent(EVENT_SCROLLING_END, docAcc);
+    await runPython(`
+      global docText, p2, range
+      docText = getUiaPattern(doc, "Text")
+      p2 = findUiaByDomId(doc, "p2")
+      range = docText.RangeFromChild(p2)
+      range.ScrollIntoView(True)
+    `);
+    await scrolled;
+    let [left, top, , height] = await runPython(
+      `range.GetBoundingRectangles()`
+    );
+    is(left, docLeft, "range is at left of document");
+    is(top, docTop, "range is at top of document");
+
+    info("Scrolling p2 to bottom");
+    scrolled = waitForEvent(EVENT_SCROLLING_END, docAcc);
+    await runPython(`
+      range.ScrollIntoView(False)
+    `);
+    await scrolled;
+    [left, top, , height] = await runPython(`range.GetBoundingRectangles()`);
+    is(left, docLeft, "range is at left of document");
+    is(top + height, docBottom, "range is at bottom of document");
+  }
+);

accessible/windows/uia/UiaTextRange.cpp

@@ -7,6 +7,7 @@
 #include "UiaTextRange.h"
 
 #include "nsAccUtils.h"
+#include "nsIAccessibleTypes.h"
 #include "TextLeafRange.h"
 #include <comdef.h>
 #include <unordered_set>
@@ -653,8 +654,18 @@ UiaTextRange::AddToSelection() { return E_NOTIMPL; }
 STDMETHODIMP
 UiaTextRange::RemoveFromSelection() { return E_NOTIMPL; }
 
-STDMETHODIMP
+// XXX Use MOZ_CAN_RUN_SCRIPT_BOUNDARY for now due to bug 1543294.
-UiaTextRange::ScrollIntoView(BOOL aAlignToTop) { return E_NOTIMPL; }
+MOZ_CAN_RUN_SCRIPT_BOUNDARY STDMETHODIMP
+UiaTextRange::ScrollIntoView(BOOL aAlignToTop) {
+  TextLeafRange range = GetRange();
+  if (!range) {
+    return CO_E_OBJNOTCONNECTED;
+  }
+  range.ScrollIntoView(aAlignToTop
+                           ? nsIAccessibleScrollType::SCROLL_TYPE_TOP_LEFT
+                           : nsIAccessibleScrollType::SCROLL_TYPE_BOTTOM_RIGHT);
+  return S_OK;
+}
 
 STDMETHODIMP
 UiaTextRange::GetChildren(__RPC__deref_out_opt SAFEARRAY** aRetVal) {