Steps to Reproduce

1. run the attached example
2. click the button to copy the sheet to another book
3. type =username in a blank cell
 

Current Result

SEVERE: Index: 1, Size: 1 when eval username
java.lang.IndexOutOfBoundsException: Index: 1, Size: 1
at java.util.ArrayList.rangeCheck(ArrayList.java:653)
at java.util.ArrayList.get(ArrayList.java:429)
at io.keikai.model.impl.BookImpl.getSheet(BookImpl.java:186)
at io.keikai.model.impl.sys.formula.EvalBook.getName(EvalBook.java:117)
at org.zkoss.poi.ss.formula.WorkbookEvaluator.getEvalForPtg(WorkbookEvaluator.java:715)
at org.zkoss.poi.ss.formula.WorkbookEvaluator.evaluateFormula(WorkbookEvaluator.java:619)
at org.zkoss.poi.ss.formula.WorkbookEvaluator.evaluateAny(WorkbookEvaluator.java:349)
at org.zkoss.poi.ss.formula.WorkbookEvaluator.evaluate(WorkbookEvaluator.java:288)
at io.keikai.model.impl.sys.formula.FormulaEngineImpl.evaluateFormula(FormulaEngineImpl.java:582)
at io.keikai.model.impl.sys.formula.FormulaEngineImpl.evaluate(FormulaEngineImpl.java:462)
at io.keikai.model.impl.CellImpl.evalFormula(CellImpl.java:200)
at io.keikai.model.impl.CellImpl.getFormulaResultType(CellImpl.java:217)
at io.keikai.ui.SpreadsheetCtrlImpl.getCellAttr(SpreadsheetCtrlImpl.java:495)
at io.keikai.ui.SpreadsheetCtrlImpl.getRangeAttrs(SpreadsheetCtrlImpl.java:382)
at io.keikai.ui.Spreadsheet.responseUpdateCell(Spreadsheet.java:2307)
at io.keikai.ui.Spreadsheet.updateCell(Spreadsheet.java:2272)
at io.keikai.ui.InnerModelEventDispatcher.onCellContentChange(InnerModelEventDispatcher.java:222)
at io.keikai.ui.ModelEventDispatcher.onEvent(ModelEventDispatcher.java:45)
at io.keikai.model.impl.EventQueueListenerAdaptor$WrappedListener.onEvent(EventQueueListenerAdaptor.java:106)
at org.zkoss.zk.ui.event.impl.DesktopEventQueue$QueueListener.onEvent(DesktopEventQueue.java:168)
at org.zkoss.zk.ui.AbstractComponent.onEvent(AbstractComponent.java:3184)
at org.zkoss.zk.ui.AbstractComponent.service(AbstractComponent.java:3154)
at org.zkoss.zk.ui.AbstractComponent.service(AbstractComponent.java:3096)
at org.zkoss.zk.ui.impl.EventProcessor.process(EventProcessor.java:138)
at org.zkoss.zk.ui.impl.UiEngineImpl.processEvent(UiEngineImpl.java:1851)
 

Expected Result

no error
 

Debug Information

• if clone a sheet in the same book, it doesn't have such error.