[Smart Text] Make SurroundingText work for input elements

third_party/WebKit/Source/core/editing/SurroundingText.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 15 matching lines @@
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "core/editing/SurroundingText.h"
 
 #include "core/dom/Document.h"
 #include "core/dom/Element.h"
 #include "core/dom/Range.h"
+#include "core/editing/EditingUtilities.h"
 #include "core/editing/Position.h"
 #include "core/editing/iterators/BackwardsCharacterIterator.h"
 #include "core/editing/iterators/CharacterIterator.h"
 
 namespace blink {
 
 SurroundingText::SurroundingText(const Range& range, unsigned max_length)
     : start_offset_in_content_(0), end_offset_in_content_(0) {
   Initialize(range.StartPosition(), range.EndPosition(), max_length);
 }
@@ skipping 10 matching lines @@
 
   const unsigned half_max_length = max_length / 2;
 
   Document* document = start_position.GetDocument();
   // The position will have no document if it is null (as in no position).
   if (!document || !document->documentElement())
     return;
   DCHECK(!document->NeedsLayoutTreeUpdate());
 
   // The forward range starts at the selection end and ends at the document's
-  // end. It will then be updated to only contain the text in the text in the
-  // right range around the selection.
+  // or the input element's end. It will then be updated to only contain the
+  // text in the right range around the selection.
+  DCHECK_EQ(RootEditableElementOf(start_position),
+            RootEditableElementOf(end_position));
+  Element* const root_editable = RootEditableElementOf(start_position);
+  Element* const root_element =
+      root_editable ? root_editable : document->documentElement();
+
   CharacterIterator forward_iterator(
       end_position,
-      Position::LastPositionInNode(document->documentElement())
-          .ParentAnchoredEquivalent(),
+      Position::LastPositionInNode(root_element).ParentAnchoredEquivalent(),
       TextIteratorBehavior::Builder().SetStopsOnFormControls(true).Build());
   // FIXME: why do we stop going trough the text if we were not able to select
   // something on the right?
   if (!forward_iterator.AtEnd())
     forward_iterator.Advance(max_length - half_max_length);
 
   EphemeralRange forward_range = forward_iterator.Range();
   if (forward_range.IsNull() ||
       !Range::Create(*document, end_position, forward_range.StartPosition())
            ->GetText()
            .length())
     return;
 
   // Same as with the forward range but with the backward range. The range
-  // starts at the document's start and ends at the selection start and will
-  // be updated.
+  // starts at the document's or input element's start and ends at the selection
+  // start and will be updated.
   BackwardsCharacterIterator backwards_iterator(
-      Position::FirstPositionInNode(document->documentElement())
-          .ParentAnchoredEquivalent(),
+      Position::FirstPositionInNode(root_element).ParentAnchoredEquivalent(),
       start_position,
       TextIteratorBehavior::Builder().SetStopsOnFormControls(true).Build());
   if (!backwards_iterator.AtEnd())
     backwards_iterator.Advance(half_max_length);
 
   const TextIteratorBehavior behavior =
       TextIteratorBehavior::NoTrailingSpaceRangeLengthBehavior();
   start_offset_in_content_ = TextIterator::RangeLength(
       backwards_iterator.EndPosition(), start_position, behavior);
   end_offset_in_content_ = TextIterator::RangeLength(
@@ skipping 15 matching lines @@
 
 unsigned SurroundingText::StartOffsetInContent() const {
   return start_offset_in_content_;
 }
 
 unsigned SurroundingText::EndOffsetInContent() const {
   return end_offset_in_content_;
 }
 
 }  // namespace blink