Fix subexpression calculation

Author: ivan-hristov-abx

calc.go

@@ -1013,13 +1013,6 @@ func (f *File) evalInfixExp(ctx *calcContext, sheet, cell string, tokens []efp.T
 				}
 			}
 
-			if isEndParenthesesToken(token) && isBeginParenthesesToken(opftStack.Peek().(efp.Token)) {
-				if arg := argsStack.Peek().(*list.List).Back(); arg != nil {
-					opfdStack.Push(arg.Value.(formulaArg))
-					argsStack.Peek().(*list.List).Remove(arg)
-				}
-			}
-
 			// check current token is opft
 			if err = f.parseToken(ctx, sheet, token, opfdStack, opftStack); err != nil {
 				return newEmptyFormulaArg(), err
@@ -1090,7 +1083,7 @@ func (f *File) evalInfixExpFunc(ctx *calcContext, sheet, cell string, token, nex
 	opftStack.Pop() // remove current function separator
 	opfStack.Pop()
 	if opfStack.Len() > 0 { // still in function stack
-		if nextToken.TType == efp.TokenTypeOperatorInfix || (opftStack.Len() > 1 && opfdStack.Len() > 0) {
+		if nextToken.TType == efp.TokenTypeOperatorInfix || opftStack.Len() > 1 {
 			// mathematics calculate in formula function
 			opfdStack.Push(arg)
 			return newEmptyFormulaArg()

calc_test.go

@@ -895,6 +895,9 @@ func TestCalcCellValue(t *testing.T) {
 		"=1+SUM(SUM(1,2*3),4)*4/3+5+(4+2)*3":  "38.6666666666667",
 		"=SUM(1+ROW())":                       "2",
 		"=SUM((SUM(2))+1)":                    "3",
+		"=IF(2<0, 1, (4))":                    "4",
+		"=IF(2>0, (1), 4)":                    "1",
+		"=IF(2>0, (A1)*2.5, 4)":               "2.5",
 		"=SUM({1,2,3,4,\"\"})":                "10",
 		// SUMIF
 		"=SUMIF(F1:F5, \"\")":             "0",