ref #65, new formula functions FORMULATEXT and TYPE

2 files changed, 87 insertions, 9 deletions

diff --git a/calc.go b/calc.go
index 8358d33..0f44912 100644
--- a/calc.go
+++ b/calc.go
@@ -416,6 +416,7 @@ type formulaFuncs struct {
 //    FLOOR
 //    FLOOR.MATH
 //    FLOOR.PRECISE
+//    FORMULATEXT
 //    FV
 //    FVSCHEDULE
 //    GAMMA
@@ -615,6 +616,7 @@ type formulaFuncs struct {
 //    TRIMMEAN
 //    TRUE
 //    TRUNC
+//    TYPE
 //    UNICHAR
 //    UNICODE
 //    UPPER
@@ -6874,7 +6876,7 @@ func (fn *formulaFuncs) ISERR(argsList *list.List) formulaArg {
 		return newErrorFormulaArg(formulaErrorVALUE, "ISERR requires 1 argument")
 	}
 	token := argsList.Front().Value.(formulaArg)
-	result := "FALSE"
+	result := false
 	if token.Type == ArgError {
 		for _, errType := range []string{
 			formulaErrorDIV, formulaErrorNAME, formulaErrorNUM,
@@ -6882,11 +6884,11 @@ func (fn *formulaFuncs) ISERR(argsList *list.List) formulaArg {
 			formulaErrorSPILL, formulaErrorCALC, formulaErrorGETTINGDATA,
 		} {
 			if errType == token.String {
-				result = "TRUE"
+				result = true
 			}
 		}
 	}
-	return newStringFormulaArg(result)
+	return newBoolFormulaArg(result)
 }
 
 // ISERROR function tests if an initial supplied expression (or value) returns
@@ -6900,7 +6902,7 @@ func (fn *formulaFuncs) ISERROR(argsList *list.List) formulaArg {
 		return newErrorFormulaArg(formulaErrorVALUE, "ISERROR requires 1 argument")
 	}
 	token := argsList.Front().Value.(formulaArg)
-	result := "FALSE"
+	result := false
 	if token.Type == ArgError {
 		for _, errType := range []string{
 			formulaErrorDIV, formulaErrorNAME, formulaErrorNA, formulaErrorNUM,
@@ -6908,11 +6910,11 @@ func (fn *formulaFuncs) ISERROR(argsList *list.List) formulaArg {
 			formulaErrorCALC, formulaErrorGETTINGDATA,
 		} {
 			if errType == token.String {
-				result = "TRUE"
+				result = true
 			}
 		}
 	}
-	return newStringFormulaArg(result)
+	return newBoolFormulaArg(result)
 }
 
 // ISEVEN function tests if a supplied number (or numeric expression)
@@ -7190,6 +7192,32 @@ func (fn *formulaFuncs) SHEETS(argsList *list.List) formulaArg {
 	return newErrorFormulaArg(formulaErrorNA, formulaErrorNA)
 }
 
+// TYPE function returns an integer that represents the value's data type. The
+// syntax of the function is:
+//
+//    TYPE(value)
+//
+func (fn *formulaFuncs) TYPE(argsList *list.List) formulaArg {
+	if argsList.Len() != 1 {
+		return newErrorFormulaArg(formulaErrorVALUE, "TYPE requires 1 argument")
+	}
+	token := argsList.Front().Value.(formulaArg)
+	switch token.Type {
+	case ArgError:
+		return newNumberFormulaArg(16)
+	case ArgMatrix:
+		return newNumberFormulaArg(64)
+	default:
+		if arg := token.ToNumber(); arg.Type != ArgError || len(token.Value()) == 0 {
+			return newNumberFormulaArg(1)
+		}
+		if arg := token.ToBool(); arg.Type != ArgError {
+			return newNumberFormulaArg(4)
+		}
+		return newNumberFormulaArg(2)
+	}
+}
+
 // T function tests if a supplied value is text and if so, returns the
 // supplied text; Otherwise, the function returns an empty text string. The
 // syntax of the function is:
@@ -7343,7 +7371,6 @@ func (fn *formulaFuncs) NOT(argsList *list.List) formulaArg {
 	case ArgNumber:
 		return newBoolFormulaArg(!(token.Number != 0))
 	case ArgError:
-
 		return token
 	}
 	return newErrorFormulaArg(formulaErrorVALUE, "NOT expects 1 boolean or numeric argument")
@@ -9415,6 +9442,32 @@ func (fn *formulaFuncs) COLUMNS(argsList *list.List) formulaArg {
 	return newNumberFormulaArg(float64(result))
 }
 
+// FORMULATEXT function returns a formula as a text string. The syntax of the
+// function is:
+//
+//    FORMULATEXT(reference)
+//
+func (fn *formulaFuncs) FORMULATEXT(argsList *list.List) formulaArg {
+	if argsList.Len() != 1 {
+		return newErrorFormulaArg(formulaErrorVALUE, "FORMULATEXT requires 1 argument")
+	}
+	refs := argsList.Front().Value.(formulaArg).cellRefs
+	col, row := 0, 0
+	if refs != nil && refs.Len() > 0 {
+		col, row = refs.Front().Value.(cellRef).Col, refs.Front().Value.(cellRef).Row
+	}
+	ranges := argsList.Front().Value.(formulaArg).cellRanges
+	if ranges != nil && ranges.Len() > 0 {
+		col, row = ranges.Front().Value.(cellRange).From.Col, ranges.Front().Value.(cellRange).From.Row
+	}
+	cell, err := CoordinatesToCellName(col, row)
+	if err != nil {
+		return newErrorFormulaArg(formulaErrorVALUE, formulaErrorVALUE)
+	}
+	formula, _ := fn.f.GetCellFormula(fn.sheet, cell)
+	return newStringFormulaArg(formula)
+}
+
 // checkHVLookupArgs checking arguments, prepare extract mode, lookup value,
 // and data for the formula functions HLOOKUP and VLOOKUP.
 func checkHVLookupArgs(name string, argsList *list.List) (idx int, lookupValue, tableArray, matchMode, errArg formulaArg) {
diff --git a/calc_test.go b/calc_test.go
index e620eb3..d01f31b 100644
--- a/calc_test.go
+++ b/calc_test.go
@@ -1005,8 +1005,9 @@ func TestCalcCellValue(t *testing.T) {
 		"=ISERR(NA())":         "FALSE",
 		"=ISERR(POWER(0,-1)))": "TRUE",
 		// ISERROR
-		"=ISERROR(A1)":   "FALSE",
-		"=ISERROR(NA())": "TRUE",
+		"=ISERROR(A1)":          "FALSE",
+		"=ISERROR(NA())":        "TRUE",
+		"=ISERROR(\"#VALUE!\")": "FALSE",
 		// ISEVEN
 		"=ISEVEN(A1)": "FALSE",
 		"=ISEVEN(A2)": "TRUE",
@@ -1055,6 +1056,14 @@ func TestCalcCellValue(t *testing.T) {
 		// SHEETS
 		"=SHEETS()":   "1",
 		"=SHEETS(A1)": "1",
+		// TYPE
+		"=TYPE(2)":        "1",
+		"=TYPE(10/2)":     "1",
+		"=TYPE(C1)":       "1",
+		"=TYPE(\"text\")": "2",
+		"=TYPE(TRUE)":     "4",
+		"=TYPE(NA())":     "16",
+		"=TYPE(MUNIT(2))": "64",
 		// T
 		"=T(\"text\")": "text",
 		"=T(N(10))":    "",
@@ -2536,6 +2545,8 @@ func TestCalcCellValue(t *testing.T) {
 		// SHEETS
 		"=SHEETS(\"\",\"\")":  "SHEETS accepts at most 1 argument",
 		"=SHEETS(\"Sheet1\")": "#N/A",
+		// TYPE
+		"=TYPE()": "TYPE requires 1 argument",
 		// T
 		"=T()":     "T requires 1 argument",
 		"=T(NA())": "#N/A",
@@ -2839,6 +2850,9 @@ func TestCalcCellValue(t *testing.T) {
 		"=COLUMNS(Sheet1)":        newInvalidColumnNameError("Sheet1").Error(),
 		"=COLUMNS(Sheet1!A1!B1)":  newInvalidColumnNameError("Sheet1").Error(),
 		"=COLUMNS(Sheet1!Sheet1)": newInvalidColumnNameError("Sheet1").Error(),
+		// FORMULATEXT
+		"=FORMULATEXT()":  "FORMULATEXT requires 1 argument",
+		"=FORMULATEXT(1)": "#VALUE!",
 		// HLOOKUP
 		"=HLOOKUP()":                     "HLOOKUP requires at least 3 arguments",
 		"=HLOOKUP(D2,D1,1,FALSE)":        "HLOOKUP requires second argument of table array",
@@ -3693,6 +3707,17 @@ func TestCalcAVERAGEIF(t *testing.T) {
 	}
 }
 
+func TestCalcFORMULATEXT(t *testing.T) {
+	f, formulaText := NewFile(), "=SUM(B1:C1)"
+	assert.NoError(t, f.SetCellFormula("Sheet1", "A1", formulaText))
+	for _, formula := range []string{"=FORMULATEXT(A1)", "=FORMULATEXT(A:A)", "=FORMULATEXT(A1:B1)"} {
+		assert.NoError(t, f.SetCellFormula("Sheet1", "D1", formula), formula)
+		result, err := f.CalcCellValue("Sheet1", "D1")
+		assert.NoError(t, err, formula)
+		assert.Equal(t, formulaText, result, formula)
+	}
+}
+
 func TestCalcHLOOKUP(t *testing.T) {
 	cellData := [][]interface{}{
 		{"Example Result Table"},