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diff --git a/libs/minikin/ScriptUtils.h b/libs/minikin/ScriptUtils.h
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+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef MINIKIN_SCRIPT_UTILS_H
+#define MINIKIN_SCRIPT_UTILS_H
+
+#define LOG_TAG "Minikin"
+
+#include <unicode/ubidi.h>
+
+#include <memory>
+
+#include "minikin/Layout.h"
+#include "minikin/Macros.h"
+#include "minikin/U16StringPiece.h"
+
+namespace minikin {
+
+// A helper class for iterating the bidi run transitions.
+class ScriptText {
+public:
+    struct RunInfo {
+        Range range;
+        hb_script_t script;
+    };
+
+    ScriptText(const U16StringPiece& textBuf, uint32_t start, uint32_t end)
+            : mTextBuf(textBuf), mRange(start, end) {}
+
+    class iterator {
+    public:
+        inline bool operator==(const iterator& o) const {
+            return mStart == o.mStart && mParent == o.mParent;
+        }
+
+        inline bool operator!=(const iterator& o) const { return !(*this == o); }
+
+        inline std::pair<Range, hb_script_t> operator*() const {
+            return std::make_pair(Range(mStart, mEnd), mScript);
+        }
+
+        inline iterator& operator++() {
+            mStart = mEnd;
+            std::tie(mEnd, mScript) = getScriptRun(mParent->mTextBuf, mParent->mRange, mStart);
+            return *this;
+        }
+
+    private:
+        friend class ScriptText;
+
+        iterator(const ScriptText* parent, uint32_t start) : mParent(parent), mStart(start) {
+            std::tie(mEnd, mScript) = getScriptRun(mParent->mTextBuf, mParent->mRange, mStart);
+        }
+
+        const ScriptText* mParent;
+        uint32_t mStart;
+        uint32_t mEnd;
+        hb_script_t mScript;
+    };
+
+    inline iterator begin() const { return iterator(this, mRange.getStart()); }
+    inline iterator end() const { return iterator(this, mRange.getEnd()); }
+
+private:
+    U16StringPiece mTextBuf;
+    Range mRange;
+
+    static std::pair<uint32_t, hb_script_t> getScriptRun(U16StringPiece text, Range range,
+                                                         uint32_t pos);
+
+    MINIKIN_PREVENT_COPY_AND_ASSIGN(ScriptText);
+};
+
+}  // namespace minikin
+
+#endif  // MINIKIN_SCRIPT_UTILS_H