The start and end arguments should be unsigned long in setSelectionRange() function

Source/core/html/HTMLTextFormControlElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 248 matching lines @@
 
         if (newSelectionEnd > end)
             newSelectionEnd += delta;
         else if (newSelectionEnd > start)
             newSelectionEnd = start + replacementLength;
     }
 
     setSelectionRange(newSelectionStart, newSelectionEnd, SelectionHasNoDirection);
 }
 
-void HTMLTextFormControlElement::setSelectionRange(int start, int end, const String& directionString)
+void HTMLTextFormControlElement::setSelectionRange(unsigned start, unsigned end, const String& directionString)
 {
     TextFieldSelectionDirection direction = SelectionHasNoDirection;
     if (directionString == "forward")
         direction = SelectionHasForwardDirection;
     else if (directionString == "backward")
         direction = SelectionHasBackwardDirection;
 
     if (direction == SelectionHasNoDirection && document().frame() && document().frame()->editor().behavior().shouldConsiderSelectionAsDirectional())
         direction = SelectionHasForwardDirection;
 
@@ skipping 59 matching lines @@
                 index += length;
         } else if (node->hasTagName(brTag)) {
             ++index;
         }
     }
 
     ASSERT(index >= 0);
     return index;
 }
 
-void HTMLTextFormControlElement::setSelectionRange(int start, int end, TextFieldSelectionDirection direction, NeedToDispatchSelectEvent eventBehaviour, SelectionOption selectionOption)
+void HTMLTextFormControlElement::setSelectionRange(unsigned start, unsigned end, TextFieldSelectionDirection direction, NeedToDispatchSelectEvent eventBehaviour, SelectionOption selectionOption)
 {
     if (openShadowRoot() || !isTextFormControl() || !inDocument())
         return;
 
     const int editorValueLength = static_cast<int>(innerEditorValue().length());

[philipj_slow, 2015/08/12 13:20:03]

Making this unsigned now would make more sense.

[tanay.c, 2015/08/14 05:39:11]

Done.

     ASSERT(editorValueLength >= 0);
-    end = std::max(std::min(end, editorValueLength), 0);
-    start = std::min(std::max(start, 0), end);
+    end = std::min<unsigned>(end, editorValueLength);
+    start = std::min<unsigned>(start, end);
     cacheSelection(start, end, direction);
 
     if (selectionOption == NotChangeSelection || (selectionOption == ChangeSelectionIfFocused && document().focusedElement() != this)) {
         if (eventBehaviour == DispatchSelectEvent)
             scheduleSelectEvent();
         return;
     }
 
     LocalFrame* frame = document().frame();
     HTMLElement* innerEditor = innerEditorElement();
     if (!frame || !innerEditor)
         return;
 
     Position startPosition = positionForIndex(innerEditor, start);
     Position endPosition = start == end ? startPosition : positionForIndex(innerEditor, end);
 
-    ASSERT(start == indexForPosition(innerEditor, startPosition));
-    ASSERT(end == indexForPosition(innerEditor, endPosition));
+    ASSERT(start == (unsigned)indexForPosition(innerEditor, startPosition));

[philipj_slow, 2015/08/12 13:20:03]

So indexForPosition() still returns int. It looks to me like it's int all the
way down here, for example the methods on Position return int and not unsigned.
Is there a clean cut that can be made at some point, without getting some
nonsensical behavior for the range INT_MAX..UINT_MAX?

[tanay.c, 2015/08/14 05:39:11]

It may not be possible to find a clean cut boundary. In that case, it would be
better to change the caller and callee function definitions to unsigned. I will
investigate the same.

+    ASSERT(end == (unsigned)indexForPosition(innerEditor, endPosition));
 
     // startPosition and endPosition can be null position for example when
     // "-webkit-user-select: none" style attribute is specified.
     if (startPosition.isNotNull() && endPosition.isNotNull()) {
         ASSERT(startPosition.anchorNode()->shadowHost() == this
             && endPosition.anchorNode()->shadowHost() == this);
     }
     VisibleSelection newSelection;
     if (direction == SelectionHasBackwardDirection)
         newSelection.setWithoutValidation(endPosition, startPosition);
@@ skipping 617 matching lines @@
 }
 
 void HTMLTextFormControlElement::copyNonAttributePropertiesFromElement(const Element& source)
 {
     const HTMLTextFormControlElement& sourceElement = static_cast<const HTMLTextFormControlElement&>(source);
     m_lastChangeWasUserEdit = sourceElement.m_lastChangeWasUserEdit;
     HTMLFormControlElement::copyNonAttributePropertiesFromElement(source);
 }
 
 } // namespace blink