Move state machines to state_machines subdir

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

 /*
  * Copyright (C) 2004, 2005, 2006, 2007 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 23 matching lines @@
 #include "core/dom/shadow/ShadowRoot.h"
 #include "core/editing/EditingStrategy.h"
 #include "core/editing/Editor.h"
 #include "core/editing/PlainTextRange.h"
 #include "core/editing/PositionIterator.h"
 #include "core/editing/VisiblePosition.h"
 #include "core/editing/VisibleSelection.h"
 #include "core/editing/VisibleUnits.h"
 #include "core/editing/iterators/TextIterator.h"
 #include "core/editing/serializers/HTMLInterchange.h"
+#include "core/editing/state_machines/BackspaceStateMachine.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/UseCounter.h"
 #include "core/html/HTMLBRElement.h"
 #include "core/html/HTMLDivElement.h"
 #include "core/html/HTMLLIElement.h"
 #include "core/html/HTMLParagraphElement.h"
 #include "core/html/HTMLSpanElement.h"
 #include "core/html/HTMLTableCellElement.h"
 #include "core/html/HTMLUListElement.h"
 #include "core/layout/LayoutObject.h"
@@ skipping 482 matching lines @@
 Position lastEditablePositionBeforePositionInRoot(const Position& position, Node& highestRoot)
 {
     return lastEditablePositionBeforePositionInRootAlgorithm<EditingStrategy>(position, highestRoot);
 }
 
 PositionInFlatTree lastEditablePositionBeforePositionInRoot(const PositionInFlatTree& position, Node& highestRoot)
 {
     return lastEditablePositionBeforePositionInRootAlgorithm<EditingInFlatTreeStrategy>(position, highestRoot);
 }
 
+template<typename StateMachine>
+int findNextBoundaryOffset(const String& str, int current)
+{
+    StateMachine machine;
+    TextSegmentationMachineState state = TextSegmentationMachineState::Invalid;
+
+    for (int i = current - 1; i >= 0; --i) {
+        state = machine.feedPrecedingCodeUnit(str[i]);
+        if (state != TextSegmentationMachineState::NeedMoreCodeUnit)
+            break;
+    }
+    if (state == TextSegmentationMachineState::NeedMoreCodeUnit)
+        state = machine.tellEndOfPrecedingText();
+    if (state == TextSegmentationMachineState::Finished)
+        return current + machine.finalizeAndGetBoundaryOffset();
+    const int length = str.length();
+    DCHECK_EQ(TextSegmentationMachineState::NeedFollowingCodeUnit, state);
+    for (int i = current; i < length; ++i) {
+        state = machine.feedFollowingCodeUnit(str[i]);
+        if (state != TextSegmentationMachineState::NeedMoreCodeUnit)
+            break;
+    }
+    return current + machine.finalizeAndGetBoundaryOffset();
+}
+
 int uncheckedPreviousOffset(const Node* node, int current)
 {
     if (!node->isTextNode())
         return current - 1;
     const String& text = toText(node)->data();
     if (text.is8Bit())
         return current - 1; // TODO(nona): Good to support CR x LF.
     TextBreakIterator* iterator = cursorMovementIterator(text.characters16(), text.length());
     if (!iterator)
         return current - 1;
     const int result = iterator->preceding(current);
     return result == TextBreakDone ? current - 1 : result;
 }
 
 static int uncheckedPreviousOffsetForBackwardDeletion(const Node* node, int current)
 {
     DCHECK_GE(current, 0);
     if (current <= 1)
         return 0;
     if (!node->isTextNode())
         return current - 1;
 
     const String& text = toText(node)->data();
-    DCHECK(static_cast<unsigned>(current - 1) < text.length());
-    if (U16_IS_TRAIL(text[--current]))
-        --current;
-    if (current < 0)
-        current = 0;
-    return current;
+    DCHECK_LT(static_cast<unsigned>(current - 1), text.length());
+    return findNextBoundaryOffset<BackspaceStateMachine>(text, current);
 }
 
 int uncheckedNextOffset(const Node* node, int current)
 {
     if (!node->isTextNode())
         return current + 1;
     const String& text = toText(node)->data();
     if (text.is8Bit())
         return current + 1; // TODO(nona): Good to support CR x LF.
     TextBreakIterator* iterator = cursorMovementIterator(text.characters16(), text.length());
@@ skipping 1092 matching lines @@
     // instead of possibly at the end of the last node before the selection
     return mostForwardCaretPosition(visiblePosition.deepEquivalent());
 }
 
 bool isTextSecurityNode(const Node* node)
 {
     return node && node->layoutObject() && node->layoutObject()->style()->textSecurity() != TSNONE;
 }
 
 } // namespace blink