From ae64d1f85985cdeb28baa5733a82ebb214c69e5e Mon Sep 17 00:00:00 2001
From: Fabio Issamu Oshiro <fabio.oshiro@gmail.com>
Date: Wed, 2 Nov 2022 12:24:28 -0300
Subject: [PATCH] fix: average #93

---
 src/formulas.js      |  6 +++++-
 test/1-basic-test.js | 15 +++++++++++++--
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/src/formulas.js b/src/formulas.js
index b18fc7c..69cf1a7 100644
--- a/src/formulas.js
+++ b/src/formulas.js
@@ -478,7 +478,11 @@ function EXP(n) {
 }
 
 function avg() {
-    return sum.apply(this, arguments) / counta.apply(this, arguments);
+    var aux = counta.apply(this, arguments);
+    if (aux == 0) {
+        throw Error('#DIV/0!');
+    }
+    return sum.apply(this, arguments) / aux;
 }
 
 function stDeviation() {
diff --git a/test/1-basic-test.js b/test/1-basic-test.js
index 9954174..f654307 100644
--- a/test/1-basic-test.js
+++ b/test/1-basic-test.js
@@ -15,8 +15,8 @@ const errorValues = {
 
 describe('XLSX_CALC', function() {
     let workbook;
-    beforeEach(function() {
-        workbook = {
+    function create_workbook() {
+        return {
             Sheets: {
                 Sheet1: {
                     A1: {},
@@ -38,6 +38,9 @@ describe('XLSX_CALC', function() {
                 }
             }
         };
+    }
+    beforeEach(function() {
+        workbook = create_workbook();
     });
 
     describe('ROUND', () => {
@@ -1023,6 +1026,14 @@ describe('XLSX_CALC', function() {
             XLSX_CALC(workbook);
             assert.equal(workbook.Sheets.Sheet1.A7.v, 0.25);
         });
+        it('should calc AVERAGE of empty cells as div by zero', function() {
+            workbook.Sheets.Sheet1 = {};
+            workbook.Sheets.Sheet1.B1 = {f: 'AVERAGE(A1:A6)'};
+            XLSX_CALC(workbook);
+            assert.equal(workbook.Sheets.Sheet1.B1.v, errorValues["#DIV/0!"]);
+            assert.equal(workbook.Sheets.Sheet1.B1.w, '#DIV/0!');
+            assert.equal(workbook.Sheets.Sheet1.B1.t, 'e');
+        });
     });
     describe('IRR', function() {
         it('calcs IRR', function() {