TestFormulaParser.java

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   this work for additional information regarding copyright ownership.
   The ASF licenses this file to You under the Apache License, Version 2.0
   (the "License"); you may not use this file except in compliance with
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   distributed under the License is distributed on an "AS IS" BASIS,
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package org.apache.poi.hssf.model;

import static org.apache.poi.hssf.model.HSSFFormulaParser.parse;
import static org.junit.jupiter.api.Assertions.*;

import java.io.IOException;
import java.util.Locale;

import org.apache.poi.hssf.HSSFTestDataSamples;
import org.apache.poi.hssf.record.NameRecord;
import org.apache.poi.hssf.record.common.UnicodeString;
import org.apache.poi.hssf.usermodel.FormulaExtractor;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFEvaluationWorkbook;
import org.apache.poi.hssf.usermodel.HSSFName;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.usermodel.TestHSSFName;
import org.apache.poi.ss.formula.FormulaParseException;
import org.apache.poi.ss.formula.FormulaParser;
import org.apache.poi.ss.formula.FormulaType;
import org.apache.poi.ss.formula.constant.ErrorConstant;
import org.apache.poi.ss.formula.ptg.*;
import org.apache.poi.ss.usermodel.BaseTestBugzillaIssues;
import org.apache.poi.ss.usermodel.FormulaError;
import org.apache.poi.ss.usermodel.FormulaEvaluator;
import org.apache.poi.ss.usermodel.Name;
import org.apache.poi.util.HexRead;
import org.apache.poi.util.LittleEndianByteArrayInputStream;
import org.junit.jupiter.api.Test;

/**
 * Test the low level formula parser functionality. High level tests are to
 * be done via usermodel/HSSFCell.setFormulaValue().
 */
final class TestFormulaParser {

    /**
     * @return parsed token array already confirmed not {@code null}
     */
    /* package */ static Ptg[] parseFormula(String formula) {
        Ptg[] result = parse(formula, null);
        assertNotNull(result, "Ptg array should not be null");
        return result;
    }
    private static String toFormulaString(Ptg[] ptgs) {
        return HSSFFormulaParser.toFormulaString(null, ptgs);
    }

    @Test
    void testSimpleFormula() {
        confirmTokenClasses("2+2",IntPtg.class, IntPtg.class, AddPtg.class);
    }

    @Test
    void testFormulaWithSpace1() {
        confirmTokenClasses(" 2 + 2 ",IntPtg.class, IntPtg.class, AddPtg.class);
    }

    @Test
    void testFormulaWithSpace2() {
        Ptg[] ptgs = parseFormula("2+ sum( 3 , 4) ");
        assertEquals(5, ptgs.length);
    }

    @Test
    void testFormulaWithSpaceNRef() {
        Ptg[] ptgs = parseFormula("sum( A2:A3 )");
        assertEquals(2, ptgs.length);
    }

    @Test
    void testFormulaWithString() {
        Ptg[] ptgs = parseFormula("\"hello\" & \"world\" ");
        assertEquals(3, ptgs.length);
    }

    @Test
    void testTRUE() {
        Ptg[] ptgs = parseFormula("TRUE");
        assertEquals(1, ptgs.length);
        BoolPtg flag  = (BoolPtg) ptgs[0];
        assertTrue(flag.getValue());
    }

    @Test
    void testSumIf() {
        Ptg[] ptgs = parseFormula("SUMIF(A1:A5,\">4000\",B1:B5)");
        assertEquals(4, ptgs.length);
    }

    /**
     * Bug Reported by xt-jens.riis@nokia.com (Jens Riis)
     * Refers to Bug <a href="http://issues.apache.org/bugzilla/show_bug.cgi?id=17582">#17582</a>
     *
     */
    @Test
    void testNonAlphaFormula() {
        Ptg[] ptgs = parseFormula("\"TOTAL[\"&F3&\"]\"");
        confirmTokenClasses(ptgs, StringPtg.class, RefPtg.class, ConcatPtg.class, StringPtg.class, ConcatPtg.class);
        assertEquals("TOTAL[", ((StringPtg)ptgs[0]).getValue());
    }

    @Test
    void testMacroFunction() throws IOException {
        // testNames.xls contains a VB function called 'myFunc'
        final String testFile = "testNames.xls";
        try (HSSFWorkbook wb = HSSFTestDataSamples.openSampleWorkbook(testFile)) {
            HSSFEvaluationWorkbook book = HSSFEvaluationWorkbook.create(wb);

            //Expected ptg stack: [NamePtg(myFunc), StringPtg(arg), (additional operands go here...), FunctionPtg(myFunc)]
            Ptg[] ptg = FormulaParser.parse("myFunc(\"arg\")", book, FormulaType.CELL, -1);
            assertEquals(3, ptg.length);

            // the name gets encoded as the first operand on the stack
            NamePtg tname = (NamePtg) ptg[0];
            assertEquals("myFunc", tname.toFormulaString(book));

            // the function's arguments are pushed onto the stack from left-to-right as OperandPtgs
            StringPtg arg = (StringPtg) ptg[1];
            assertEquals("arg", arg.getValue());

            // The external FunctionPtg is the last Ptg added to the stack
            // During formula evaluation, this Ptg pops off the appropriate number of
            // arguments (getNumberOfOperands()) and pushes the result on the stack
            AbstractFunctionPtg tfunc = (AbstractFunctionPtg) ptg[2]; //FuncVarPtg
            assertTrue(tfunc.isExternalFunction());

            // confirm formula parsing is case-insensitive
            FormulaParser.parse("mYfUnC(\"arg\")", book, FormulaType.CELL, -1);

            // confirm formula parsing doesn't care about argument count or type
            // this should only throw an error when evaluating the formula.
            FormulaParser.parse("myFunc()", book, FormulaType.CELL, -1);
            FormulaParser.parse("myFunc(\"arg\", 0, TRUE)", book, FormulaType.CELL, -1);

            // A completely unknown formula name (not saved in workbook) should still be parseable and renderable
            // but will throw an NotImplementedFunctionException or return a #NAME? error value if evaluated.
            FormulaParser.parse("yourFunc(\"arg\")", book, FormulaType.CELL, -1);

            // Verify that myFunc and yourFunc were successfully added to Workbook names
            try (HSSFWorkbook wb2 = HSSFTestDataSamples.writeOutAndReadBack(wb)) {
                // HSSFWorkbook/EXCEL97-specific side-effects user-defined function names must be added to Workbook's defined names in order to be saved.
                HSSFName myFunc = wb2.getName("myFunc");
                assertNotNull(myFunc);
                assertEqualsIgnoreCase("myFunc", myFunc.getNameName());
                HSSFName yourFunc = wb2.getName("yourFunc");
                assertNotNull(yourFunc);
                assertEqualsIgnoreCase("yourFunc", yourFunc.getNameName());
            }
        }
    }

    private static void assertEqualsIgnoreCase(String expected, String actual) {
        assertEquals(expected.toLowerCase(Locale.ROOT), actual.toLowerCase(Locale.ROOT));
    }

    @Test
    void testEmbeddedSlash() {
        confirmTokenClasses("HYPERLINK(\"http://www.jakarta.org\",\"Jakarta\")",
                        StringPtg.class, StringPtg.class, FuncVarPtg.class);
    }

    @Test
    void testConcatenate() {
        confirmTokenClasses("CONCATENATE(\"first\",\"second\")",
                StringPtg.class, StringPtg.class, FuncVarPtg.class);
    }

    @Test
    void testWorksheetReferences() throws IOException {
        try (HSSFWorkbook wb = new HSSFWorkbook()) {

            HSSFSheet sheet1 = wb.createSheet("NoQuotesNeeded");
            sheet1.createRow(0).createCell(0).setCellValue("NoQuotesNeeded");
            HSSFSheet sheet2 = wb.createSheet("Quotes Needed Here &#$@");
            sheet2.createRow(0).createCell(0).setCellValue("Quotes Needed Here &#$@");

            HSSFSheet sheet = wb.createSheet("Test");
            HSSFRow row = sheet.createRow(0);

            FormulaEvaluator evaluator = wb.getCreationHelper().createFormulaEvaluator();
            HSSFCell cell;
            String act;

            cell = row.createCell(0);
            cell.setCellFormula("NoQuotesNeeded!A1");
            act = evaluator.evaluate(cell).getStringValue();
            assertEquals("NoQuotesNeeded", act);

            cell = row.createCell(1);
            cell.setCellFormula("'Quotes Needed Here &#$@'!A1");
            act = evaluator.evaluate(cell).getStringValue();
            assertEquals("Quotes Needed Here &#$@", act);
        }
    }

    @Test
    void testUnaryMinus() {
        confirmTokenClasses("-A1", RefPtg.class, UnaryMinusPtg.class);
    }

    @Test
    void testUnaryPlus() {
        confirmTokenClasses("+A1", RefPtg.class, UnaryPlusPtg.class);
    }

    /**
     * There may be multiple ways to encode an expression involving {@link UnaryPlusPtg}
     * or {@link UnaryMinusPtg}.  These may be perfectly equivalent from a formula
     * evaluation perspective, or formula rendering.  However, differences in the way
     * POI encodes formulas may cause unnecessary confusion.  These non-critical tests
     * check that POI follows the same encoding rules as Excel.
     */
    @Test
    void testExactEncodingOfUnaryPlusAndMinus() {
        // as tested in Excel:
        confirmUnary("-3", -3, NumberPtg.class);
        confirmUnary("--4", -4, NumberPtg.class, UnaryMinusPtg.class);
        confirmUnary("+++5", 5, IntPtg.class, UnaryPlusPtg.class, UnaryPlusPtg.class);
        confirmUnary("++-6", -6, NumberPtg.class, UnaryPlusPtg.class, UnaryPlusPtg.class);

        // Spaces muck things up a bit.  It would be clearer why the following cases are
        // reasonable if POI encoded tAttrSpace in the right places.
        // Otherwise these differences look capricious.
        confirmUnary("+ 12", 12, IntPtg.class, UnaryPlusPtg.class);
        confirmUnary("- 13", 13, IntPtg.class, UnaryMinusPtg.class);
    }

    private static void confirmUnary(String formulaText, double val, Class<?>...expectedTokenTypes) {
        Ptg[] ptgs = parseFormula(formulaText);
        confirmTokenClasses(ptgs, expectedTokenTypes);
        Ptg ptg0 = ptgs[0];
        if (ptg0 instanceof IntPtg) {
            IntPtg intPtg = (IntPtg) ptg0;
            assertEquals((int)val, intPtg.getValue());
        } else if (ptg0 instanceof NumberPtg) {
            NumberPtg numberPtg = (NumberPtg) ptg0;
            assertEquals(val, numberPtg.getValue(), 0.0);
        } else {
            fail("bad ptg0 " + ptg0);
        }
    }

    @Test
    void testLeadingSpaceInString() {
        String value = "  hi  ";
        Ptg[] ptgs = parseFormula("\"" + value + "\"");
        confirmTokenClasses(ptgs, StringPtg.class);
        assertEquals(((StringPtg) ptgs[0]).getValue(), value, "ptg0 contains exact value");
    }

    @Test
    void testLookupAndMatchFunctionArgs() {
        Ptg[] ptgs = parseFormula("lookup(A1, A3:A52, B3:B52)");
        confirmTokenClasses(ptgs, RefPtg.class, AreaPtg.class, AreaPtg.class, FuncVarPtg.class);
        assertEquals(Ptg.CLASS_VALUE, ptgs[0].getPtgClass(), "ptg0 has Value class");

        ptgs = parseFormula("match(A1, A3:A52)");
        confirmTokenClasses(ptgs, RefPtg.class, AreaPtg.class, FuncVarPtg.class);
        assertEquals(Ptg.CLASS_VALUE, ptgs[0].getPtgClass(), "ptg0 has Value class");
    }

    /** bug 33160*/
    @Test
    void testLargeInt() {
        confirmTokenClasses("40", IntPtg.class);
        confirmTokenClasses("40000", IntPtg.class);
    }

    /** bug 33160 */
    @Test
    void testSimpleLongFormula() {
        confirmTokenClasses("40000/2", IntPtg.class, IntPtg.class, DividePtg.class);
    }

    /** bug 35027, underscore in sheet name */
    @Test
    void testUnderscore() throws IOException {
        try (HSSFWorkbook wb = new HSSFWorkbook()) {
            HSSFSheet sheet1 = wb.createSheet("Cash_Flow");
            sheet1.createRow(0).createCell(0).setCellValue("Cash_Flow");

            HSSFSheet sheet = wb.createSheet("Test");
            HSSFRow row = sheet.createRow(0);
            HSSFCell cell;

            cell = row.createCell(0);
            cell.setCellFormula("Cash_Flow!A1");

            FormulaEvaluator evaluator = wb.getCreationHelper().createFormulaEvaluator();
            String act = evaluator.evaluate(cell).getStringValue();
            assertEquals("Cash_Flow", act);
        }
    }

    /** bug 49725, defined names with underscore */
    @Test
    void testNamesWithUnderscore() throws IOException {
        HSSFWorkbook wb = new HSSFWorkbook(); //or new XSSFWorkbook();
        HSSFSheet sheet = wb.createSheet("NamesWithUnderscore");

        HSSFName nm;

        nm = wb.createName();
        nm.setNameName("DA6_LEO_WBS_Number");
        nm.setRefersToFormula("33");

        nm = wb.createName();
        nm.setNameName("DA6_LEO_WBS_Name");
        nm.setRefersToFormula("33");

        nm = wb.createName();
        nm.setNameName("A1_");
        nm.setRefersToFormula("22");

        nm = wb.createName();
        nm.setNameName("_A1");
        nm.setRefersToFormula("11");

        nm = wb.createName();
        nm.setNameName("A_1");
        nm.setRefersToFormula("44");

        nm = wb.createName();
        nm.setNameName("A_1_");
        nm.setRefersToFormula("44");

        HSSFRow row = sheet.createRow(0);
        HSSFCell cell = row.createCell(0);

        cell.setCellFormula("DA6_LEO_WBS_Number*2");
        assertEquals("DA6_LEO_WBS_Number*2", cell.getCellFormula());

        cell.setCellFormula("(A1_*_A1+A_1)/A_1_");
        assertEquals("(A1_*_A1+A_1)/A_1_", cell.getCellFormula());

        cell.setCellFormula("INDEX(DA6_LEO_WBS_Name,MATCH($A3,DA6_LEO_WBS_Number,0))");
        assertEquals("INDEX(DA6_LEO_WBS_Name,MATCH($A3,DA6_LEO_WBS_Number,0))", cell.getCellFormula());

        wb.close();
    }

    // bug 38396 : Formula with exponential numbers not parsed correctly.
    @Test
    void testExponentialParsing() {
        confirmTokenClasses("1.3E21/2",  NumberPtg.class, IntPtg.class, DividePtg.class);
        confirmTokenClasses("1322E21/2", NumberPtg.class, IntPtg.class, DividePtg.class);
        confirmTokenClasses("1.3E1/2",   NumberPtg.class, IntPtg.class, DividePtg.class);
    }

    @Test
    void testExponentialInSheet() throws IOException {
        HSSFWorkbook wb = new HSSFWorkbook();

        wb.createSheet("Cash_Flow");

        HSSFSheet sheet = wb.createSheet("Test");
        HSSFRow row = sheet.createRow(0);
        HSSFCell cell = row.createCell(0);
        String formula;

        cell.setCellFormula("1.3E21/3");
        formula = cell.getCellFormula();
        assertEquals("1.3E+21/3", formula);

        cell.setCellFormula("-1.3E21/3");
        formula = cell.getCellFormula();
        assertEquals("-1.3E+21/3", formula);

        cell.setCellFormula("1322E21/3");
        formula = cell.getCellFormula();
        assertEquals("1.322E+24/3", formula);

        cell.setCellFormula("-1322E21/3");
        formula = cell.getCellFormula();
        assertEquals("-1.322E+24/3", formula);

        cell.setCellFormula("1.3E1/3");
        formula = cell.getCellFormula();
        assertEquals("13/3", formula);

        cell.setCellFormula("-1.3E1/3");
        formula = cell.getCellFormula();
        assertEquals("-13/3", formula);

        cell.setCellFormula("1.3E-4/3");
        formula = cell.getCellFormula();
        assertEquals("0.00013/3", formula);

        cell.setCellFormula("-1.3E-4/3");
        formula = cell.getCellFormula();
        assertEquals("-0.00013/3", formula);

        cell.setCellFormula("13E-15/3");
        formula = cell.getCellFormula();
        assertEquals("0.000000000000013/3", formula);

        cell.setCellFormula("-13E-15/3");
        formula = cell.getCellFormula();
        assertEquals("-0.000000000000013/3", formula);

        cell.setCellFormula("1.3E3/3");
        formula = cell.getCellFormula();
        assertEquals("1300/3", formula);

        cell.setCellFormula("-1.3E3/3");
        formula = cell.getCellFormula();
        assertEquals("-1300/3", formula);

        cell.setCellFormula("1300000000000000/3");
        formula = cell.getCellFormula();
        assertEquals("1300000000000000/3", formula);

        cell.setCellFormula("-1300000000000000/3");
        formula = cell.getCellFormula();
        assertEquals("-1300000000000000/3", formula);

        cell.setCellFormula("-10E-1/3.1E2*4E3/3E4");
        formula = cell.getCellFormula();
        assertEquals("-1/310*4000/30000", formula);

        wb.close();
    }

    @Test
    void testNumbers() throws IOException {
        HSSFWorkbook wb = new HSSFWorkbook();

        wb.createSheet("Cash_Flow");

        HSSFSheet sheet = wb.createSheet("Test");
        HSSFRow row = sheet.createRow(0);
        HSSFCell cell = row.createCell(0);
        String formula;

        // starts from decimal point

        cell.setCellFormula(".1");
        formula = cell.getCellFormula();
        assertEquals("0.1", formula);

        cell.setCellFormula("+.1");
        formula = cell.getCellFormula();
        assertEquals("0.1", formula);

        cell.setCellFormula("-.1");
        formula = cell.getCellFormula();
        assertEquals("-0.1", formula);

        // has exponent

        cell.setCellFormula("10E1");
        formula = cell.getCellFormula();
        assertEquals("100", formula);

        cell.setCellFormula("10E+1");
        formula = cell.getCellFormula();
        assertEquals("100", formula);

        cell.setCellFormula("10E-1");
        formula = cell.getCellFormula();
        assertEquals("1", formula);

        wb.close();
    }

    @Test
    void testRanges() throws IOException {
        HSSFWorkbook wb = new HSSFWorkbook();

        wb.createSheet("Cash_Flow");

        HSSFSheet sheet = wb.createSheet("Test");
        HSSFRow row = sheet.createRow(0);
        HSSFCell cell = row.createCell(0);
        String formula;

        cell.setCellFormula("A1.A2");
        formula = cell.getCellFormula();
        assertEquals("A1:A2", formula);

        cell.setCellFormula("A1..A2");
        formula = cell.getCellFormula();
        assertEquals("A1:A2", formula);

        cell.setCellFormula("A1...A2");
        formula = cell.getCellFormula();
        assertEquals("A1:A2", formula);

        wb.close();
    }

    @Test
    void testMultiSheetReference() throws IOException {
        HSSFWorkbook wb = new HSSFWorkbook();

        wb.createSheet("Cash_Flow");
        wb.createSheet("Test Sheet");
        wb.createSheet("Sheet 3>");

        HSSFSheet sheet = wb.createSheet("Test");
        HSSFRow row = sheet.createRow(0);
        HSSFCell cell = row.createCell(0);
        String formula;


        // References to a single cell:

        // One sheet
        cell.setCellFormula("Cash_Flow!A1");
        formula = cell.getCellFormula();
        assertEquals("Cash_Flow!A1", formula);

        // Then the other
        cell.setCellFormula("'Test Sheet'!A1");
        formula = cell.getCellFormula();
        assertEquals("'Test Sheet'!A1", formula);

        // Now both
        cell.setCellFormula("'Cash_Flow:Test Sheet'!A1");
        formula = cell.getCellFormula();
        assertEquals("'Cash_Flow:Test Sheet'!A1", formula);

        // special character
        cell.setCellFormula("'Cash_Flow:Sheet 3>'!A1");
        formula = cell.getCellFormula();
        assertEquals("'Cash_Flow:Sheet 3>'!A1", formula);

        // References to a range (area) of cells:

        // One sheet
        cell.setCellFormula("Cash_Flow!A1:B2");
        formula = cell.getCellFormula();
        assertEquals("Cash_Flow!A1:B2", formula);

        // Then the other
        cell.setCellFormula("'Test Sheet'!A1:B2");
        formula = cell.getCellFormula();
        assertEquals("'Test Sheet'!A1:B2", formula);

        // Now both
        cell.setCellFormula("'Cash_Flow:Test Sheet'!A1:B2");
        formula = cell.getCellFormula();
        assertEquals("'Cash_Flow:Test Sheet'!A1:B2", formula);

        wb.close();
    }

    /**
     * Test for bug observable at svn revision 618865 (5-Feb-2008)<br>
     * a formula consisting of a single no-arg function got rendered without the function braces
     */
    @Test
    void testToFormulaStringZeroArgFunction() throws IOException {
        HSSFWorkbook book = new HSSFWorkbook();

        Ptg[] ptgs = {
                FuncPtg.create(10),
        };
        assertEquals("NA()", HSSFFormulaParser.toFormulaString(book, ptgs));

        book.close();
    }

    @Test
    void testPercent() {

        confirmTokenClasses("5%", IntPtg.class, PercentPtg.class);
        // spaces OK
        confirmTokenClasses(" 250 % ", IntPtg.class, PercentPtg.class);
        // double percent OK
        confirmTokenClasses("12345.678%%", NumberPtg.class, PercentPtg.class, PercentPtg.class);

        // percent of a bracketed expression
        confirmTokenClasses("(A1+35)%*B1%", RefPtg.class, IntPtg.class, AddPtg.class, ParenthesisPtg.class,
                PercentPtg.class, RefPtg.class, PercentPtg.class, MultiplyPtg.class);

        // percent of a text quantity
        confirmTokenClasses("\"8.75\"%", StringPtg.class, PercentPtg.class);

        // percent to the power of
        confirmTokenClasses("50%^3", IntPtg.class, PercentPtg.class, IntPtg.class, PowerPtg.class);

        // things that parse OK but would *evaluate* to an error
        confirmTokenClasses("\"abc\"%", StringPtg.class, PercentPtg.class);
        confirmTokenClasses("#N/A%", ErrPtg.class, PercentPtg.class);
    }

    /**
     * Tests combinations of various operators in the absence of brackets
     */
    @Test
    void testPrecedenceAndAssociativity() {

        // TRUE=TRUE=2=2  evaluates to FALSE
        confirmTokenClasses("TRUE=TRUE=2=2", BoolPtg.class, BoolPtg.class, EqualPtg.class,
                IntPtg.class, EqualPtg.class, IntPtg.class, EqualPtg.class);

        //  2^3^2    evaluates to 64 not 512
        confirmTokenClasses("2^3^2", IntPtg.class, IntPtg.class, PowerPtg.class,
                IntPtg.class, PowerPtg.class);

        // "abc" & 2 + 3 & "def"   evaluates to "abc5def"
        confirmTokenClasses("\"abc\"&2+3&\"def\"", StringPtg.class, IntPtg.class, IntPtg.class,
                AddPtg.class, ConcatPtg.class, StringPtg.class, ConcatPtg.class);

        //  (1 / 2) - (3 * 4)
        confirmTokenClasses("1/2-3*4", IntPtg.class, IntPtg.class, DividePtg.class,
                IntPtg.class, IntPtg.class, MultiplyPtg.class, SubtractPtg.class);

        // 2 * (2^2)
        // NOT: (2 *2) ^ 2 -> int int multiply int power
        confirmTokenClasses("2*2^2", IntPtg.class, IntPtg.class, IntPtg.class, PowerPtg.class, MultiplyPtg.class);

        //  2^200% -> 2 not 1.6E58
        confirmTokenClasses("2^200%", IntPtg.class, IntPtg.class, PercentPtg.class, PowerPtg.class);
    }

    /* package */ static Ptg[] confirmTokenClasses(String formula, Class<?>...expectedClasses) {
        Ptg[] ptgs = parseFormula(formula);
        confirmTokenClasses(ptgs, expectedClasses);
        return ptgs;
    }

    private static void confirmTokenClasses(Ptg[] ptgs, Class<?>...expectedClasses) {
        assertEquals(expectedClasses.length, ptgs.length);
        for (int i = 0; i < expectedClasses.length; i++) {
            assertSame(expectedClasses[i], ptgs[i].getClass(),
                "difference at token[" + i + "] for Ptg " + ptgs[i] + ": expected ("
                + expectedClasses[i].getName() + ") but got ("
                + ptgs[i].getClass().getName() + ")");
        }
    }

    @Test
    void testPower() {
        confirmTokenClasses("2^5", IntPtg.class, IntPtg.class, PowerPtg.class);
    }

    private static Ptg parseSingleToken(String formula, Class<? extends Ptg> ptgClass) {
        Ptg[] ptgs = parseFormula(formula);
        assertEquals(1, ptgs.length);
        Ptg result = ptgs[0];
        assertSame(ptgClass, result.getClass());
        return result;
    }

    @Test
    void testParseNumber() {
        IntPtg ip;

        // bug 33160
        ip = (IntPtg) parseSingleToken("40", IntPtg.class);
        assertEquals(40, ip.getValue());
        ip = (IntPtg) parseSingleToken("40000", IntPtg.class);
        assertEquals(40000, ip.getValue());

        // check the upper edge of the IntPtg range:
        ip = (IntPtg) parseSingleToken("65535", IntPtg.class);
        assertEquals(65535, ip.getValue());
        NumberPtg np = (NumberPtg) parseSingleToken("65536", NumberPtg.class);
        assertEquals(65536, np.getValue(), 0);

        np = (NumberPtg) parseSingleToken("65534.6", NumberPtg.class);
        assertEquals(65534.6, np.getValue(), 0);
    }

    @Test
    void testMissingArgs() {
        confirmTokenClasses("if(A1, ,C1)",
                RefPtg.class,
                AttrPtg.class, // tAttrIf
                MissingArgPtg.class,
                AttrPtg.class, // tAttrSkip
                RefPtg.class,
                AttrPtg.class, // tAttrSkip
                FuncVarPtg.class
        );

        confirmTokenClasses("counta( , A1:B2, )", MissingArgPtg.class, AreaPtg.class, MissingArgPtg.class,
                FuncVarPtg.class);
    }

    @Test
    void testParseErrorLiterals() {

        confirmParseErrorLiteral(ErrPtg.NULL_INTERSECTION, "#NULL!");
        confirmParseErrorLiteral(ErrPtg.DIV_ZERO, "#DIV/0!");
        confirmParseErrorLiteral(ErrPtg.VALUE_INVALID, "#VALUE!");
        confirmParseErrorLiteral(ErrPtg.REF_INVALID, "#REF!");
        confirmParseErrorLiteral(ErrPtg.NAME_INVALID, "#NAME?");
        confirmParseErrorLiteral(ErrPtg.NUM_ERROR, "#NUM!");
        confirmParseErrorLiteral(ErrPtg.N_A, "#N/A");
        parseFormula("HLOOKUP(F7,#REF!,G7,#REF!)");
    }

    private static void confirmParseErrorLiteral(ErrPtg expectedToken, String formula) {
        assertEquals(expectedToken, parseSingleToken(formula, ErrPtg.class));
    }

    /**
     * To aid readability the parameters have been encoded with single quotes instead of double
     * quotes.  This method converts single quotes to double quotes before performing the parse
     * and result check.
     */
    private static void confirmStringParse(String singleQuotedValue) {
        // formula: internal quotes become double double, surround with double quotes
        String formula = '"' + singleQuotedValue.replaceAll("'", "\"\"") + '"';
        String expectedValue = singleQuotedValue.replace('\'', '"');

        StringPtg sp = (StringPtg) parseSingleToken(formula, StringPtg.class);
        assertEquals(expectedValue, sp.getValue());
    }

    @Test
    void testParseStringLiterals_bug28754() throws IOException {

        StringPtg sp;
        try {
            sp = (StringPtg) parseSingleToken("\"test\"\"ing\"", StringPtg.class);
        } catch (RuntimeException e) {
            if(e.getMessage().startsWith("Cannot Parse")) {
                fail("Identified bug 28754a");
            }
            throw e;
        }
        assertEquals("test\"ing", sp.getValue());

        try (HSSFWorkbook wb = new HSSFWorkbook()) {
            HSSFSheet sheet = wb.createSheet();
            wb.setSheetName(0, "Sheet1");

            HSSFRow row = sheet.createRow(0);
            HSSFCell cell = row.createCell(0);
            cell.setCellFormula("right(\"test\"\"ing\", 3)");
            String actualCellFormula = cell.getCellFormula();
            assertNotEquals("RIGHT(\"test\"ing\",3)", actualCellFormula, "Identified bug 28754b");
            assertEquals("RIGHT(\"test\"\"ing\",3)", actualCellFormula);
        }
    }

    @Test
    void testParseStringLiterals() {
        confirmStringParse("goto considered harmful");

        confirmStringParse("goto 'considered' harmful");

        confirmStringParse("");
        confirmStringParse("'");
        confirmStringParse("''");
        confirmStringParse("' '");
        confirmStringParse(" ' ");
    }

    @Test
    void testParseSumIfSum() {
        String formulaString;
        Ptg[] ptgs;
        ptgs = parseFormula("sum(5, 2, if(3>2, sum(A1:A2), 6))");
        formulaString = toFormulaString(ptgs);
        assertEquals("SUM(5,2,IF(3>2,SUM(A1:A2),6))", formulaString);

        ptgs = parseFormula("if(1<2,sum(5, 2, if(3>2, sum(A1:A2), 6)),4)");
        formulaString = toFormulaString(ptgs);
        assertEquals("IF(1<2,SUM(5,2,IF(3>2,SUM(A1:A2),6)),4)", formulaString);
    }

    @Test
    void testParserErrors() {
        parseExpectedException(" 12 . 345  ");
        parseExpectedException("1 .23  ");

        parseExpectedException("sum(#NAME)");
        parseExpectedException("1 + #N / A * 2");
        parseExpectedException("#value?");
        parseExpectedException("#DIV/ 0+2");


        parseExpectedException("IF(TRUE)");
        parseExpectedException("countif(A1:B5, C1, D1)");

        parseExpectedException("(");
        parseExpectedException(")");
        parseExpectedException("+");
        parseExpectedException("42+");

        parseExpectedException("IF(");
    }

    private static void parseExpectedException(String formula) {
        FormulaParseException e = assertThrows(FormulaParseException.class, () -> parseFormula(formula));
        assertNotNull(e.getMessage());
    }

    @Test
    void testSetFormulaWithRowBeyond32768_Bug44539() throws IOException {

        HSSFWorkbook wb = new HSSFWorkbook();
        HSSFSheet sheet = wb.createSheet();
        wb.setSheetName(0, "Sheet1");

        HSSFRow row = sheet.createRow(0);
        HSSFCell cell = row.createCell(0);
        cell.setCellFormula("SUM(A32769:A32770)");
        assertNotEquals("SUM(A-32767:A-32766)", cell.getCellFormula(), "Identified bug 44539");
        assertEquals("SUM(A32769:A32770)", cell.getCellFormula());

        wb.close();
    }

    @Test
    void testSpaceAtStartOfFormula() {
        // Simulating cell formula of "= 4" (note space)
        // The same Ptg array can be observed if an excel file is saved with that exact formula

        AttrPtg spacePtg = AttrPtg.createSpace(AttrPtg.SpaceType.SPACE_BEFORE, 1);
        Ptg[] ptgs = { spacePtg, new IntPtg(4), };
        String formulaString;
        try {
            formulaString = toFormulaString(ptgs);
        } catch (IllegalStateException e) {
            if(e.getMessage().equalsIgnoreCase("too much stuff left on the stack")) {
                fail("Identified bug 44609");
            }
            // else some unexpected error
            throw e;
        }
        // FormulaParser strips spaces anyway
        assertEquals("4", formulaString);

        ptgs = new Ptg[] { new IntPtg(3), spacePtg, new IntPtg(4), spacePtg, AddPtg.instance, };
        formulaString = toFormulaString(ptgs);
        assertEquals("3+4", formulaString);
    }

    /**
     * Checks some internal error detecting logic ('stack underflow error' in toFormulaString)
     */
    @Test
    void testTooFewOperandArgs() {
        // Simulating badly encoded cell formula of "=/1"
        // Not sure if Excel could ever produce this
        Ptg[] ptgs = {
                // Excel would probably have put tMissArg here
                new IntPtg(1),
                DividePtg.instance,
        };
        IllegalStateException e = assertThrows(IllegalStateException.class, () -> toFormulaString(ptgs));
        assertTrue(e.getMessage().startsWith("Too few arguments supplied to operation"));
    }

    /**
     * Make sure that POI uses the right Func Ptg when encoding formulas.  Functions with variable
     * number of args should get FuncVarPtg, functions with fixed args should get FuncPtg.<p>
     *
     * Prior to the fix for bug 44675 POI would encode FuncVarPtg for all functions.  In many cases
     * Excel tolerates the wrong Ptg and evaluates the formula OK (e.g. SIN), but in some cases
     * (e.g. COUNTIF) Excel fails to evaluate the formula, giving '#VALUE!' instead.
     */
    @Test
    void testFuncPtgSelection() {

        Ptg[] ptgs = parseFormula("countif(A1:A2, 1)");
        assertEquals(3, ptgs.length);
        assertFalse(ptgs[2] instanceof FuncVarPtg, "Identified bug 44675");
        confirmTokenClasses(ptgs, AreaPtg.class, IntPtg.class, FuncPtg.class);

        confirmTokenClasses("sin(1)", IntPtg.class, FuncPtg.class);
    }

    @Test
    void testWrongNumberOfFunctionArgs() throws IOException {
        confirmArgCountMsg("sin()", "Too few arguments to function 'SIN'. Expected 1 but got 0.");
        confirmArgCountMsg("countif(1, 2, 3, 4)", "Too many arguments to function 'COUNTIF'. Expected 2 but got 4.");
        confirmArgCountMsg("index(1, 2, 3, 4, 5, 6)", "Too many arguments to function 'INDEX'. At most 4 were expected but got 6.");
        confirmArgCountMsg("vlookup(1, 2)", "Too few arguments to function 'VLOOKUP'. At least 3 were expected but got 2.");
    }

    private static void confirmArgCountMsg(String formula, String expectedMessage) throws IOException {
        try (HSSFWorkbook book = new HSSFWorkbook()) {
            FormulaParseException e = assertThrows(FormulaParseException.class, () -> parse(formula, book));
            confirmParseException(e, expectedMessage);
        }
    }

    @Test
    void testParseErrorExpectedMsg() {
        FormulaParseException e;
        e = assertThrows(FormulaParseException.class, () -> parseFormula("round(3.14;2)"));
        confirmParseException(e, "Parse error near char 10 ';' in specified formula 'round(3.14;2)'. Expected ',' or ')'");

        e = assertThrows(FormulaParseException.class, () -> parseFormula(" =2+2"));
        confirmParseException(e, "The specified formula ' =2+2' starts with an equals sign which is not allowed.");
    }

    /**
     * this function name has a dot in it.
     */
    @Test
    void testParseErrorTypeFunction() {

        Ptg[] ptgs;
        try {
            ptgs = parseFormula("error.type(A1)");
        } catch (IllegalArgumentException e) {
            if (e.getMessage().equals("Invalid Formula cell reference: 'error'")) {
                fail("Identified bug 45334");
            }
            throw e;
        }
        confirmTokenClasses(ptgs, RefPtg.class, FuncPtg.class);
        assertEquals("ERROR.TYPE", ((FuncPtg) ptgs[1]).getName());
    }

    @Test
    void testNamedRangeThatLooksLikeCell() throws IOException {
        try (HSSFWorkbook wb = new HSSFWorkbook()) {
            HSSFSheet sheet = wb.createSheet("Sheet1");
            HSSFName name = wb.createName();
            name.setRefersToFormula("Sheet1!B1");
            name.setNameName("pfy1");

            Ptg[] ptgs;
            try {
                ptgs = parse("count(pfy1)", wb);
            } catch (IllegalArgumentException e) {
                if (e.getMessage().equals("Specified colIx (1012) is out of range")) {
                    fail("Identified bug 45354");
                }
                throw e;
            }
            confirmTokenClasses(ptgs, NamePtg.class, FuncVarPtg.class);

            HSSFCell cell = sheet.createRow(0).createCell(0);
            cell.setCellFormula("count(pfy1)");
            assertEquals("COUNT(pfy1)", cell.getCellFormula());
            FormulaParseException e = assertThrows(FormulaParseException.class, () -> cell.setCellFormula("count(pf1)"));
            confirmParseException(e, "Specified named range 'pf1' does not exist in the current workbook.");
            cell.setCellFormula("count(fp1)"); // plain cell ref, col is in range
        }
    }

    @Test
    void testParseAreaRefHighRow_bug45358() throws IOException {
        Ptg[] ptgs;
        AreaI aptg;

        HSSFWorkbook book = new HSSFWorkbook();
        book.createSheet("Sheet1");

        ptgs = parse("Sheet1!A10:A40000", book);
        aptg = (AreaI) ptgs[0];
        assertNotEquals(-25537, aptg.getLastRow(), "Identified bug 45358");
        assertEquals(39999, aptg.getLastRow());

        ptgs = parse("Sheet1!A10:A65536", book);
        aptg = (AreaI) ptgs[0];
        assertEquals(65535, aptg.getLastRow());

        // plain area refs should be ok too
        ptgs = parseFormula("A10:A65536");
        aptg = (AreaI) ptgs[0];
        assertEquals(65535, aptg.getLastRow());

        book.close();
    }

    @Test
    void testParseArray()  {
        Ptg[] ptgs;
        ptgs = parseFormula("mode({1,2,2,#REF!;FALSE,3,3,2})");
        confirmTokenClasses(ptgs, ArrayPtg.class, FuncVarPtg.class);
        assertEquals("{1,2,2,#REF!;FALSE,3,3,2}", ptgs[0].toFormulaString());

        ArrayPtg aptg = (ArrayPtg) ptgs[0];
        Object[][] values = aptg.getTokenArrayValues();
        assertEquals(ErrorConstant.valueOf(FormulaError.REF.getCode()), values[0][3]);
        assertEquals(Boolean.FALSE, values[1][0]);
    }

    @Test
    void testParseStringElementInArray() {
        Ptg[] ptgs;
        ptgs = parseFormula("MAX({\"5\"},3)");
        confirmTokenClasses(ptgs, ArrayPtg.class, IntPtg.class, FuncVarPtg.class);
        Object element = ((ArrayPtg)ptgs[0]).getTokenArrayValues()[0][0];
        // this would cause ClassCastException below
        assertFalse(element instanceof UnicodeString, "Wrong encoding of array element value");
        assertSame(String.class, element.getClass());

        // make sure the formula encodes OK
        int encSize = Ptg.getEncodedSize(ptgs);
        byte[] data = new byte[encSize];
        Ptg.serializePtgs(ptgs, data, 0);
        byte[] expData = HexRead.readFromString(
                "20 00 00 00 00 00 00 00 " // tArray
                + "1E 03 00 "      // tInt(3)
                + "42 02 07 00 "   // tFuncVar(MAX) 2-arg
                + "00 00 00 "      // Array data: 1 col, 1 row
                + "02 01 00 00 35" // elem (type=string, len=1, "5")
        );
        assertArrayEquals(expData, data);
        int initSize = Ptg.getEncodedSizeWithoutArrayData(ptgs);
        Ptg[] ptgs2 = Ptg.readTokens(initSize, new LittleEndianByteArrayInputStream(data));
        confirmTokenClasses(ptgs2, ArrayPtg.class, IntPtg.class, FuncVarPtg.class);
    }

    @Test
    void testParseArrayNegativeElement() {
        Ptg[] ptgs;
        try {
            ptgs = parseFormula("{-42}");
        } catch (FormulaParseException e) {
            if (e.getMessage().equals("Parse error near char 1 '-' in specified formula '{-42}'. Expected Integer")) {
                fail("Identified bug - failed to parse negative array element.");
            }
            throw e;
        }
        confirmTokenClasses(ptgs, ArrayPtg.class);
        Object element = ((ArrayPtg)ptgs[0]).getTokenArrayValues()[0][0];

        assertEquals(-42.0, (Double) element, 0.0);

        // Should be able to handle whitespace between unary minus and digits (Excel
        // accepts this formula after presenting the user with a confirmation dialog).
        ptgs = parseFormula("{- 5}");
        element = ((ArrayPtg)ptgs[0]).getTokenArrayValues()[0][0];
        assertEquals(-5.0, (Double) element, 0.0);
    }

    @Test
    void testRangeOperator() throws IOException {

        HSSFWorkbook wb = new HSSFWorkbook();
        HSSFSheet sheet = wb.createSheet();
        HSSFCell cell = sheet.createRow(0).createCell(0);

        wb.setSheetName(0, "Sheet1");
        cell.setCellFormula("Sheet1!B$4:Sheet1!$C1"); // explicit range ':' operator
        assertEquals("Sheet1!B$4:Sheet1!$C1", cell.getCellFormula());

        cell.setCellFormula("Sheet1!B$4:$C1"); // plain area ref
        assertEquals("Sheet1!B1:$C$4", cell.getCellFormula()); // note - area ref is normalised

        cell.setCellFormula("Sheet1!$C1...B$4"); // different syntax for plain area ref
        assertEquals("Sheet1!B1:$C$4", cell.getCellFormula());

        // with funny sheet name
        wb.setSheetName(0, "A1...A2");
        cell.setCellFormula("A1...A2!B1");
        assertEquals("A1...A2!B1", cell.getCellFormula());

        wb.close();
    }

    @Test
    void testBooleanNamedSheet() throws IOException {
        HSSFWorkbook wb = new HSSFWorkbook();
        HSSFSheet sheet = wb.createSheet("true");
        HSSFCell cell = sheet.createRow(0).createCell(0);
        cell.setCellFormula("'true'!B2");

        assertEquals("'true'!B2", cell.getCellFormula());

        wb.close();
    }

    @Test
    void testParseExternalWorkbookReference() throws IOException {
        HSSFWorkbook wbA = HSSFTestDataSamples.openSampleWorkbook("multibookFormulaA.xls");
        HSSFCell cell = wbA.getSheetAt(0).getRow(0).getCell(0);

        // make sure formula in sample is as expected
        assertEquals("[multibookFormulaB.xls]BSheet1!B1", cell.getCellFormula());
        Ptg[] expectedPtgs = FormulaExtractor.getPtgs(cell);
        confirmSingle3DRef(expectedPtgs, 1);

        // now try (re-)parsing the formula
        Ptg[] actualPtgs = parse("[multibookFormulaB.xls]BSheet1!B1", wbA);
        confirmSingle3DRef(actualPtgs, 1); // externalSheetIndex 1 -> BSheet1

        // try parsing a formula pointing to a different external sheet
        Ptg[] otherPtgs = parse("[multibookFormulaB.xls]AnotherSheet!B1", wbA);
        confirmSingle3DRef(otherPtgs, 0); // externalSheetIndex 0 -> AnotherSheet

        // try setting the same formula in a cell
        cell.setCellFormula("[multibookFormulaB.xls]AnotherSheet!B1");
        assertEquals("[multibookFormulaB.xls]AnotherSheet!B1", cell.getCellFormula());

        wbA.close();
    }

    private static void confirmSingle3DRef(Ptg[] ptgs, int expectedExternSheetIndex) {
        assertEquals(1, ptgs.length);
        Ptg ptg0 = ptgs[0];
        assertTrue(ptg0 instanceof Ref3DPtg);
        assertEquals(expectedExternSheetIndex, ((Ref3DPtg)ptg0).getExternSheetIndex());
    }

    @Test
    void testUnion() throws IOException {
        String formula = "Sheet1!$B$2:$C$3,OFFSET(Sheet1!$E$2:$E$4,1,Sheet1!$A$1),Sheet1!$D$6";
        HSSFWorkbook wb = new HSSFWorkbook();
        wb.createSheet("Sheet1");
        Ptg[] ptgs = FormulaParser.parse(formula, HSSFEvaluationWorkbook.create(wb), FormulaType.CELL, -1);

        confirmTokenClasses(ptgs,
                // TODO - AttrPtg.class, // Excel prepends this
                MemFuncPtg.class,
                Area3DPtg.class,
                Area3DPtg.class,
                IntPtg.class,
                Ref3DPtg.class,
                FuncVarPtg.class,
                UnionPtg.class,
                Ref3DPtg.class,
                UnionPtg.class
        );
        MemFuncPtg mf = (MemFuncPtg)ptgs[0];
        assertEquals(45, mf.getLenRefSubexpression());

        // We don't check the type of the operands.
        confirmTokenClasses("1,2", MemAreaPtg.class, IntPtg.class, IntPtg.class, UnionPtg.class);

        wb.close();
    }

    @Test
    void testIntersection() throws IOException {
       String formula = "Sheet1!$B$2:$C$3 OFFSET(Sheet1!$E$2:$E$4, 1,Sheet1!$A$1) Sheet1!$D$6";
        HSSFWorkbook wb = new HSSFWorkbook();
        wb.createSheet("Sheet1");
        Ptg[] ptgs = FormulaParser.parse(formula, HSSFEvaluationWorkbook.create(wb), FormulaType.CELL, -1);

        confirmTokenClasses(ptgs,
                // TODO - AttrPtg.class, // Excel prepends this
                MemFuncPtg.class,
                Area3DPtg.class,
                Area3DPtg.class,
                IntPtg.class,
                Ref3DPtg.class,
                FuncVarPtg.class,
                IntersectionPtg.class,
                Ref3DPtg.class,
                IntersectionPtg.class
        );
        MemFuncPtg mf = (MemFuncPtg)ptgs[0];
        assertEquals(45, mf.getLenRefSubexpression());

        // This used to be an error but now parses.  Union has the same behaviour.
        confirmTokenClasses("1 2", MemAreaPtg.class, IntPtg.class, IntPtg.class, IntersectionPtg.class);

        wb.close();
    }

    @Test
    void testComparisonInParen() {
        confirmTokenClasses("(A1 > B2)",
            RefPtg.class,
            RefPtg.class,
            GreaterThanPtg.class,
            ParenthesisPtg.class
        );
    }

    @Test
    void testUnionInParen() {
        confirmTokenClasses("(A1:B2,B2:C3)",
          MemAreaPtg.class,
          AreaPtg.class,
          AreaPtg.class,
          UnionPtg.class,
          ParenthesisPtg.class
        );
    }

    @Test
    void testIntersectionInParen() {
        confirmTokenClasses("(A1:B2 B2:C3)",
            MemAreaPtg.class,
            AreaPtg.class,
            AreaPtg.class,
            IntersectionPtg.class,
            ParenthesisPtg.class
        );
    }

    // https://bz.apache.org/bugzilla/show_bug.cgi?id=60980
    @Test
    void testIntersectionInFunctionArgs() {
        confirmTokenClasses("SUM(A1:B2 B2:C3)",
                MemAreaPtg.class,
                AreaPtg.class,
                AreaPtg.class,
                IntersectionPtg.class,
                AttrPtg.class
        );
    }

    @Test
    void testIntersectionNamesInFunctionArgs() {
        HSSFWorkbook wb = new HSSFWorkbook();

        HSSFName name1 = wb.createName();
        name1.setNameName("foo1");
        name1.setRefersToFormula("A1:A3");

        HSSFName name2 = wb.createName();
        name2.setNameName("foo2");
        name2.setRefersToFormula("A1:B3");

        Ptg[] ptgs = FormulaParser.parse("SUM(foo1 foo2)", HSSFEvaluationWorkbook.create(wb), FormulaType.CELL, -1);

        confirmTokenClasses(ptgs,
                MemFuncPtg.class,
                NamePtg.class,
                NamePtg.class,
                IntersectionPtg.class,
                AttrPtg.class
        );
    }

    @Test
    void testRange_bug46643() throws IOException {
        String formula = "Sheet1!A1:Sheet1!B3";
        HSSFWorkbook wb = new HSSFWorkbook();
        wb.createSheet("Sheet1");
        Ptg[] ptgs = FormulaParser.parse(formula, HSSFEvaluationWorkbook.create(wb), FormulaType.CELL, -1, -1);

        if (ptgs.length == 3) {
            confirmTokenClasses(ptgs, Ref3DPtg.class, Ref3DPtg.class, RangePtg.class);
            fail("Identified bug 46643");
        }

        confirmTokenClasses(ptgs,
                MemFuncPtg.class,
                Ref3DPtg.class,
                Ref3DPtg.class,
                RangePtg.class
        );
        MemFuncPtg mf = (MemFuncPtg)ptgs[0];
        assertEquals(15, mf.getLenRefSubexpression());
        wb.close();
    }

    /** Named ranges with backslashes, e.g. 'POI\\2009' */
    @Test
    void testBackSlashInNames() throws IOException {
        HSSFWorkbook wb = new HSSFWorkbook();

        HSSFName name = wb.createName();
        name.setNameName("POI\\2009");
        name.setRefersToFormula("Sheet1!$A$1");

        HSSFSheet sheet = wb.createSheet();
        HSSFRow row = sheet.createRow(0);

        HSSFCell cell_C1 =  row.createCell(2);
        cell_C1.setCellFormula("POI\\2009");
        assertEquals("POI\\2009", cell_C1.getCellFormula());

        HSSFCell cell_D1 = row.createCell(2);
        cell_D1.setCellFormula("NOT(POI\\2009=\"3.5-final\")");
        assertEquals("NOT(POI\\2009=\"3.5-final\")", cell_D1.getCellFormula());

        wb.close();
    }

    /**
     * See the related/similar test: {@link BaseTestBugzillaIssues#bug42448()}
     */
    @Test
    void testParseAbnormalSheetNamesAndRanges_bug42448() throws IOException {
        try (HSSFWorkbook wb = new HSSFWorkbook()) {
            wb.createSheet("A");
            assertDoesNotThrow(() -> parse("SUM(A!C7:A!C67)", wb), "Identified bug 42448");
            // the exact example from the bugzilla description:
            parse("SUMPRODUCT(A!C7:A!C67, B8:B68) / B69", wb);
        }
    }

    @Test
    void testRangeFuncOperand_bug46951() throws IOException {
        try (HSSFWorkbook wb = new HSSFWorkbook()) {
            Ptg[] ptgs;
            try {
                ptgs = parse("SUM(C1:OFFSET(C1,0,B1))", wb);
            } catch (RuntimeException e) {
                if (e.getMessage().equals("Specified named range 'OFFSET' does not exist in the current workbook.")) {
                    fail("Identified bug 46951");
                }
                throw e;
            }
            confirmTokenClasses(ptgs,
                MemFuncPtg.class, // [len=23]
                RefPtg.class, // [C1]
                RefPtg.class, // [C1]
                IntPtg.class, // [0]
                RefPtg.class, // [B1]
                FuncVarPtg.class, // [OFFSET nArgs=3]
                RangePtg.class, //
                AttrPtg.class // [sum ]
            );
        }
    }

    @Test
    void testUnionOfFullCollFullRowRef() throws IOException {
        parseFormula("3:4");
        Ptg[] ptgs = parseFormula("$Z:$AC");
        confirmTokenClasses(ptgs, AreaPtg.class);
        parseFormula("B:B");

        ptgs = parseFormula("$11:$13");
        confirmTokenClasses(ptgs, AreaPtg.class);

        ptgs = parseFormula("$A:$A,$1:$4");
        confirmTokenClasses(ptgs, MemAreaPtg.class,
                AreaPtg.class,
                AreaPtg.class,
                UnionPtg.class
        );

        HSSFWorkbook wb = new HSSFWorkbook();
        wb.createSheet("Sheet1");
        ptgs = parse("Sheet1!$A:$A,Sheet1!$1:$4", wb);
        confirmTokenClasses(ptgs, MemFuncPtg.class,
                Area3DPtg.class,
                Area3DPtg.class,
                UnionPtg.class
        );

        ptgs = parse("'Sheet1'!$A:$A,'Sheet1'!$1:$4", wb);
        confirmTokenClasses(ptgs,
                MemFuncPtg.class,
                Area3DPtg.class,
                Area3DPtg.class,
                UnionPtg.class
        );

        wb.createSheet("Sh't1");
        ptgs = parse("'Sh''t1'!$A:$A,'Sh''t1'!$1:$4", wb);
        confirmTokenClasses(ptgs,
                MemFuncPtg.class,
                Area3DPtg.class,
                Area3DPtg.class,
                UnionPtg.class
        );
        assertEquals(1, ((Area3DPtg)ptgs[1]).getExternSheetIndex());
        assertEquals(1, ((Area3DPtg)ptgs[2]).getExternSheetIndex());

        wb.close();
    }

    @Test
    void testParseSheetNameWithMultipleSingleQuotes() throws IOException {
        try (HSSFWorkbook wb = new HSSFWorkbook()) {
            wb.createSheet("Sh''t1");
            Ptg[] ptgs = parse("'Sh''''t1'!$A:$A,'Sh''''t1'!$1:$4", wb);
            confirmTokenClasses(ptgs,
                    MemFuncPtg.class,
                    Area3DPtg.class,
                    Area3DPtg.class,
                    UnionPtg.class
            );
            assertEquals(0, ((Area3DPtg)ptgs[1]).getExternSheetIndex());
            assertEquals(0, ((Area3DPtg)ptgs[2]).getExternSheetIndex());
        }
    }

    @Test
    void testExplicitRangeWithTwoSheetNames() throws IOException {
        HSSFWorkbook wb = new HSSFWorkbook();
        wb.createSheet("Sheet1");
        Ptg[] ptgs = parse("Sheet1!F1:Sheet1!G2", wb);
        confirmTokenClasses(ptgs,
                MemFuncPtg.class,
                Ref3DPtg.class,
                Ref3DPtg.class,
                RangePtg.class
        );
        MemFuncPtg mf;
        mf = (MemFuncPtg)ptgs[0];
        assertEquals(15, mf.getLenRefSubexpression());
        wb.close();
    }

    /**
     * Checks that the area-ref and explicit range operators get the right associativity
     * and that the {@link MemFuncPtg} / {@link MemAreaPtg} is added correctly
     */
    @Test
    void testComplexExplicitRangeEncodings() {

        Ptg[] ptgs;
        ptgs = parseFormula("SUM(OFFSET(A1,0,0):B2:C3:D4:E5:OFFSET(F6,1,1):G7)");
        confirmTokenClasses(ptgs,
            // AttrPtg.class, // [volatile ] // POI doesn't do this yet (Apr 2009)
            MemFuncPtg.class, // len 57
            RefPtg.class, // [A1]
            IntPtg.class, // [0]
            IntPtg.class, // [0]
            FuncVarPtg.class, // [OFFSET nArgs=3]
            AreaPtg.class, // [B2:C3]
            RangePtg.class,
            AreaPtg.class, // [D4:E5]
            RangePtg.class,
            RefPtg.class, // [F6]
            IntPtg.class, // [1]
            IntPtg.class, // [1]
            FuncVarPtg.class, // [OFFSET nArgs=3]
            RangePtg.class,
            RefPtg.class, // [G7]
            RangePtg.class,
            AttrPtg.class // [sum ]
        );

        MemFuncPtg mf = (MemFuncPtg)ptgs[0];
        assertEquals(57, mf.getLenRefSubexpression());
        assertEquals("D4:E5", ptgs[7].toFormulaString());
        assertTrue(((AttrPtg)ptgs[16]).isSum());

        ptgs = parseFormula("SUM(A1:B2:C3:D4)");
        confirmTokenClasses(ptgs,
            // AttrPtg.class, // [volatile ] // POI doesn't do this yet (Apr 2009)
                MemAreaPtg.class, // len 19
                AreaPtg.class, // [A1:B2]
                AreaPtg.class, // [C3:D4]
                RangePtg.class,
                AttrPtg.class // [sum ]
        );
        MemAreaPtg ma = (MemAreaPtg)ptgs[0];
        assertEquals(19, ma.getLenRefSubexpression());
    }


    /**
     * Mostly confirming that erroneous conditions are detected.  Actual error message wording is not critical.
     *
     */
    @Test
    void testEdgeCaseParserErrors() throws IOException {
        HSSFWorkbook wb = new HSSFWorkbook();
        wb.createSheet("Sheet1");

        //confirmParseError(wb, "A1:ROUND(B1,1)", "The RHS of the range operator ':' at position 3 is not a proper reference.");

        confirmParseError(wb, "Sheet1!!!", "Parse error near char 7 '!' in specified formula 'Sheet1!!!'. Expected number, string, defined name, or data table");
        confirmParseError(wb, "Sheet1!.Name", "Parse error near char 7 '.' in specified formula 'Sheet1!.Name'. Expected number, string, defined name, or data table");
        confirmParseError(wb, "Sheet1!Sheet1", "Specified name 'Sheet1' for sheet Sheet1 not found");
        confirmParseError(wb, "Sheet1!F:Sheet1!G", "'Sheet1!F' is not a proper reference.");
        confirmParseError(wb, "Sheet1!F..foobar", "Complete area reference expected after sheet name at index 11.");
        confirmParseError(wb, "Sheet1!A .. B", "Dotted range (full row or column) expression 'A .. B' must not contain whitespace.");
        confirmParseError(wb, "Sheet1!A...B", "Dotted range (full row or column) expression 'A...B' must have exactly 2 dots.");
        confirmParseError(wb, "Sheet1!A foobar", "Second part of cell reference expected after sheet name at index 10.");

        confirmParseError(wb, "foobar", "Specified named range 'foobar' does not exist in the current workbook.");
        confirmParseError(wb, "A1:1", "The RHS of the range operator ':' at position 3 is not a proper reference.");
        wb.close();
    }

    private static void confirmParseError(HSSFWorkbook wb, String formula, String expectedMessage) {
        FormulaParseException e = assertThrows(FormulaParseException.class, () -> parse(formula, wb));
        confirmParseException(e, expectedMessage);
    }

    /**
     * In bug 47078, POI had trouble evaluating a defined name flagged as 'complex'.
     * POI should also be able to parse such defined names.
     */
    @Test
    void testParseComplexName() throws IOException {

        // Mock up a spreadsheet to match the critical details of the sample
        try (HSSFWorkbook wb = new HSSFWorkbook()) {
            wb.createSheet("Sheet1");
            HSSFName definedName = wb.createName();
            definedName.setNameName("foo");
            definedName.setRefersToFormula("Sheet1!B2");

            // Set the complex flag - POI doesn't usually manipulate this flag
            NameRecord nameRec = TestHSSFName.getNameRecord(definedName);
            nameRec.setOptionFlag((short) 0x10); // 0x10 -> complex

            Ptg[] result;
            try {
                result = parse("1+foo", wb);
            } catch (FormulaParseException e) {
                if (e.getMessage().equals("Specified name 'foo' is not a range as expected.")) {
                    fail("Identified bug 47078c");
                }
                throw e;
            }
            confirmTokenClasses(result, IntPtg.class, NamePtg.class, AddPtg.class);
        }
    }

    /**
     * Zero is not a valid row number so cell references like 'A0' are not valid.
     * Actually, they should be treated like defined names.
     * <br>
     * In addition, leading zeros (on the row component) should be removed from cell
     * references during parsing.
     */
    @Test
    void testZeroRowRefs() throws IOException {
        String badCellRef = "B0"; // bad because zero is not a valid row number
        String leadingZeroCellRef = "B000001"; // this should get parsed as "B1"
        HSSFWorkbook wb = new HSSFWorkbook();

        FormulaParseException e = assertThrows(FormulaParseException.class, () -> parse(badCellRef, wb),
            "Identified bug 47312b - Shouldn't be able to parse cell ref '" + badCellRef + "'.");
        confirmParseException(e, "Specified named range '" + badCellRef + "' does not exist in the current workbook.");

        Ptg[] ptgs;
        try {
            ptgs = parse(leadingZeroCellRef, wb);
            assertEquals("B1", ptgs[0].toFormulaString());
        } catch (FormulaParseException e2) {
            confirmParseException(e2, "Specified named range '" + leadingZeroCellRef + "' does not exist in the current workbook.");
            // close but no cigar
            fail("Identified bug 47312c - '" + leadingZeroCellRef + "' should parse as 'B1'.");
        }

        // create a defined name called 'B0' and try again
        Name n = wb.createName();
        n.setNameName("B0");
        n.setRefersToFormula("1+1");
        ptgs = parse("B0", wb);
        confirmTokenClasses(ptgs, NamePtg.class);

        wb.close();
    }

    private static void confirmParseException(FormulaParseException e, String expMsg) {
        assertEquals(expMsg, e.getMessage());
    }

    @Test
    void test57196_Formula() throws IOException {
        HSSFWorkbook wb = new HSSFWorkbook();
        Ptg[] ptgs = parse("DEC2HEX(HEX2DEC(O8)-O2+D2)", wb, FormulaType.CELL, -1);
        assertNotNull(ptgs, "Ptg array should not be null");

        confirmTokenClasses(ptgs,
            NameXPtg.class, // ??
            NameXPtg.class, // ??
            RefPtg.class, // O8
            FuncVarPtg.class, // HEX2DEC
            RefPtg.class, // O2
            SubtractPtg.class,
            RefPtg.class,   // D2
            AddPtg.class,
            FuncVarPtg.class // DEC2HEX
        );

        RefPtg o8 = (RefPtg) ptgs[2];
        FuncVarPtg hex2Dec = (FuncVarPtg) ptgs[3];
        RefPtg o2 = (RefPtg) ptgs[4];
        RefPtg d2 = (RefPtg) ptgs[6];
        FuncVarPtg dec2Hex = (FuncVarPtg) ptgs[8];

        assertEquals("O8", o8.toFormulaString());
        assertEquals(255, hex2Dec.getFunctionIndex());
        //assertEquals("", hex2Dec.toString());
        assertEquals("O2", o2.toFormulaString());
        assertEquals("D2", d2.toFormulaString());
        assertEquals(255, dec2Hex.getFunctionIndex());

        wb.close();
    }
}