Index: third_party/WebKit/Source/core/editing/state_machines/BackwardCodePointStateMachine.h |
diff --git a/third_party/WebKit/Source/core/editing/state_machines/BackwardCodePointStateMachine.h b/third_party/WebKit/Source/core/editing/state_machines/BackwardCodePointStateMachine.h |
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index 0000000000000000000000000000000000000000..502517188fd96b79c0c2b6da1baf74d61e43115a |
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+// Copyright 2017 The Chromium Authors. All rights reserved. |
+// Use of this source code is governed by a BSD-style license that can be |
+// found in the LICENSE file. |
+ |
+#ifndef BackwardCodePointStateMachine_h |
+#define BackwardCodePointStateMachine_h |
+ |
+#include "core/CoreExport.h" |
+#include "core/editing/state_machines/TextSegmentationMachineState.h" |
+#include "wtf/Allocator.h" |
+#include "wtf/Noncopyable.h" |
+#include "wtf/text/Unicode.h" |
+ |
+namespace blink { |
+ |
+class CORE_EXPORT BackwardCodePointStateMachine { |
+ STACK_ALLOCATED(); |
+ WTF_MAKE_NONCOPYABLE(BackwardCodePointStateMachine); |
+ |
+ public: |
+ BackwardCodePointStateMachine(); |
+ ~BackwardCodePointStateMachine() = default; |
+ |
+ // Prepares by feeding preceding text. |
+ TextSegmentationMachineState feedPrecedingCodeUnit(UChar codeUnit); |
+ |
+ // Finds boundary offset by feeding following text. |
+ TextSegmentationMachineState feedFollowingCodeUnit(UChar codeUnit); |
+ |
+ // Returns true if we are at code point boundary. |
+ bool atCodePointBoundary(); |
+ |
+ // Returns the next boundary offset. |
+ int getBoundaryOffset(); |
+ |
+ // Resets the internal state to the initial state. |
+ void reset(); |
+ |
+ private: |
+ enum class BackwardCodePointState; |
+ |
+ // The number of code units to be deleted. |
+ // Nothing to delete if there is an invalid surrogate pair. |
+ int m_codeUnitsToBeDeleted = 0; |
+ |
+ // The internal state. |
+ BackwardCodePointState m_state; |
+}; |
+ |
+} // namespace blink |
+ |
+#endif |