Introduce previousPositionOf() for VisiblePosition

Source/core/editing/commands/CompositeEditCommand.cpp

 /*
  * Copyright (C) 2005, 2006, 2007, 2008 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 687 matching lines @@
     LayoutText* layoutText = textNode->layoutObject();
     if (layoutText && !layoutText->style()->collapseWhiteSpace())
         return;
 
     // Delete collapsed whitespace so that inserting nbsps doesn't uncollapse it.
     Position upstreamPos = mostBackwardCaretPosition(position);
     deleteInsignificantText(upstreamPos, mostForwardCaretPosition(position));
     position = mostForwardCaretPosition(upstreamPos);
 
     VisiblePosition visiblePos(position);
-    VisiblePosition previousVisiblePos(visiblePos.previous());
+    VisiblePosition previousVisiblePos(previousPositionOf(visiblePos));
     replaceCollapsibleWhitespaceWithNonBreakingSpaceIfNeeded(previousVisiblePos);
     replaceCollapsibleWhitespaceWithNonBreakingSpaceIfNeeded(visiblePos);
 }
 
 void CompositeEditCommand::replaceCollapsibleWhitespaceWithNonBreakingSpaceIfNeeded(const VisiblePosition& visiblePosition)
 {
     if (!isCollapsibleWhitespace(visiblePosition.characterAfter()))
         return;
     Position pos = mostForwardCaretPosition(visiblePosition.deepEquivalent());
     if (!pos.computeContainerNode() || !pos.computeContainerNode()->isTextNode())
@@ skipping 404 matching lines @@
 // It is currently used only by IndentOutdentCommand but it is meant to be used in the
 // future by several other commands such as InsertList and the align commands.
 // The blockElement parameter is the element to move the paragraph to,
 // outerNode is the top element of the paragraph hierarchy.
 
 void CompositeEditCommand::moveParagraphWithClones(const VisiblePosition& startOfParagraphToMove, const VisiblePosition& endOfParagraphToMove, HTMLElement* blockElement, Node* outerNode)
 {
     ASSERT(outerNode);
     ASSERT(blockElement);
 
-    VisiblePosition beforeParagraph = startOfParagraphToMove.previous();
+    VisiblePosition beforeParagraph = previousPositionOf(startOfParagraphToMove);
     VisiblePosition afterParagraph(endOfParagraphToMove.next());
 
     // We upstream() the end and downstream() the start so that we don't include collapsed whitespace in the move.
     // When we paste a fragment, spaces after the end and before the start are treated as though they were rendered.
     Position start = mostForwardCaretPosition(startOfParagraphToMove.deepEquivalent());
     Position end = startOfParagraphToMove.deepEquivalent() == endOfParagraphToMove.deepEquivalent() ? start : mostBackwardCaretPosition(endOfParagraphToMove.deepEquivalent());
     if (comparePositions(start, end) > 0)
         end = start;
 
     cloneParagraphUnderNewElement(start, end, outerNode, blockElement);
@@ skipping 54 matching lines @@
             startIndex = 0;
             if (startInParagraph)
                 startIndex = TextIterator::rangeLength(startOfParagraphToMove.toParentAnchoredPosition(), visibleStart.toParentAnchoredPosition(), true);
 
             endIndex = 0;
             if (endInParagraph)
                 endIndex = TextIterator::rangeLength(startOfParagraphToMove.toParentAnchoredPosition(), visibleEnd.toParentAnchoredPosition(), true);
         }
     }
 
-    VisiblePosition beforeParagraph = startOfParagraphToMove.previous(CannotCrossEditingBoundary);
+    VisiblePosition beforeParagraph = previousPositionOf(startOfParagraphToMove, CannotCrossEditingBoundary);
     VisiblePosition afterParagraph(endOfParagraphToMove.next(CannotCrossEditingBoundary));
 
     // We upstream() the end and downstream() the start so that we don't include collapsed whitespace in the move.
     // When we paste a fragment, spaces after the end and before the start are treated as though they were rendered.
     Position start = mostForwardCaretPosition(startOfParagraphToMove.deepEquivalent());
     Position end = mostBackwardCaretPosition(endOfParagraphToMove.deepEquivalent());
 
     // FIXME: This is an inefficient way to preserve style on nodes in the paragraph to move. It
     // shouldn't matter though, since moved paragraphs will usually be quite small.
     RefPtrWillBeRawPtr<DocumentFragment> fragment = startOfParagraphToMove.deepEquivalent() != endOfParagraphToMove.deepEquivalent() ?
@@ skipping 146 matching lines @@
         return false;
 
     VisiblePosition caret(endingSelection().visibleStart());
     HTMLQuoteElement* highestBlockquote = toHTMLQuoteElement(highestEnclosingNodeOfType(caret.deepEquivalent(), &isMailHTMLBlockquoteElement));
     if (!highestBlockquote)
         return false;
 
     if (!isStartOfParagraph(caret) || !isEndOfParagraph(caret))
         return false;
 
-    VisiblePosition previous(caret.previous(CannotCrossEditingBoundary));
+    VisiblePosition previous(previousPositionOf(caret, CannotCrossEditingBoundary));
     // Only move forward if there's nothing before the caret, or if there's unquoted content before it.
     if (enclosingNodeOfType(previous.deepEquivalent(), &isMailHTMLBlockquoteElement))
         return false;
 
     RefPtrWillBeRawPtr<HTMLBRElement> br = createBreakElement(document());
     // We want to replace this quoted paragraph with an unquoted one, so insert a br
     // to hold the caret before the highest blockquote.
     insertNodeBefore(br, highestBlockquote);
     VisiblePosition atBR(positionBeforeNode(br.get()));
     // If the br we inserted collapsed, for example foo<br><blockquote>...</blockquote>, insert
@@ skipping 116 matching lines @@
 }
 
 DEFINE_TRACE(CompositeEditCommand)
 {
     visitor->trace(m_commands);
     visitor->trace(m_composition);
     EditCommand::trace(visitor);
 }
 
 } // namespace blink