From 0e40daecb6fa6ec60b8474ce2c4757ef10e515b8 Mon Sep 17 00:00:00 2001
From: n1073645 <n1073645@gmail.com>
Date: Mon, 9 Mar 2020 09:13:02 +0000
Subject: [PATCH 1/2] Generates both the checksum and checkdigit.

---
 src/core/operations/LuhnChecksum.mjs | 23 ++++++++++++++++++-----
 1 file changed, 18 insertions(+), 5 deletions(-)

diff --git a/src/core/operations/LuhnChecksum.mjs b/src/core/operations/LuhnChecksum.mjs
index 24549072..e6d5fe2b 100644
--- a/src/core/operations/LuhnChecksum.mjs
+++ b/src/core/operations/LuhnChecksum.mjs
@@ -23,18 +23,19 @@ class LuhnChecksum extends Operation {
         this.description = "The Luhn algorithm, also known as the modulus 10 or mod 10 algorithm, is a simple checksum formula used to validate a variety of identification numbers, such as credit card numbers, IMEI numbers, Canadian Social Insurance Numbers.";
         this.infoURL = "https://wikipedia.org/wiki/Luhn_algorithm";
         this.inputType = "string";
-        this.outputType = "number";
+        this.outputType = "string";
         this.args = [];
     }
 
     /**
-     * @param {string} input
-     * @param {Object[]} args
+     * Generates the Luhn Checksum from the input.
+     *
+     * @param {string} inputStr
      * @returns {number}
      */
-    run(input, args) {
+    checksum(inputStr) {
         let even = false;
-        return input.split("").reverse().reduce((acc, elem) => {
+        return inputStr.split("").reverse().reduce((acc, elem) => {
 
             // Convert element to integer.
             let temp = parseInt(elem, 10);
@@ -57,6 +58,18 @@ class LuhnChecksum extends Operation {
         }, 0)  % 10;
     }
 
+    /**
+     * @param {string} input
+     * @param {Object[]} args
+     * @returns {string}
+     */
+    run(input, args) {
+        const checkSum = this.checksum(input).toString();
+        let checkDigit = this.checksum(input+"0");
+        checkDigit =  (checkDigit === 0 ? 0 : (10-checkDigit)).toString();
+        return "Checksum: " + checkSum + "\n\nCheckdigit: " + checkDigit + "\n\nLuhn Validated String: "+ input + checkDigit;
+    }
+
 }
 
 export default LuhnChecksum;

From 54cb2d268b9eb0c6afa7d30c76995d07563729ec Mon Sep 17 00:00:00 2001
From: n1073645 <n1073645@gmail.com>
Date: Mon, 9 Mar 2020 09:37:34 +0000
Subject: [PATCH 2/2] Luhn checksum tests

---
 src/core/operations/LuhnChecksum.mjs    |  6 ++++++
 tests/operations/tests/LuhnChecksum.mjs | 24 +++++++++++++++++++++++-
 2 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/src/core/operations/LuhnChecksum.mjs b/src/core/operations/LuhnChecksum.mjs
index e6d5fe2b..d9aff649 100644
--- a/src/core/operations/LuhnChecksum.mjs
+++ b/src/core/operations/LuhnChecksum.mjs
@@ -64,9 +64,15 @@ class LuhnChecksum extends Operation {
      * @returns {string}
      */
     run(input, args) {
+
+        if (!(input)) return "0";
+
         const checkSum = this.checksum(input).toString();
+
         let checkDigit = this.checksum(input+"0");
+
         checkDigit =  (checkDigit === 0 ? 0 : (10-checkDigit)).toString();
+
         return "Checksum: " + checkSum + "\n\nCheckdigit: " + checkDigit + "\n\nLuhn Validated String: "+ input + checkDigit;
     }
 
diff --git a/tests/operations/tests/LuhnChecksum.mjs b/tests/operations/tests/LuhnChecksum.mjs
index 28b17854..c5c4c6b7 100644
--- a/tests/operations/tests/LuhnChecksum.mjs
+++ b/tests/operations/tests/LuhnChecksum.mjs
@@ -11,7 +11,29 @@ TestRegister.addTests([
     {
         name: "Luhn Checksum on standard data",
         input: "35641709012469",
-        expectedOutput: "7",
+        expectedOutput: "Checksum: 7\n\nCheckdigit: 0\n\nLuhn Validated String: 356417090124690",
+        recipeConfig: [
+            {
+                op: "Luhn Checksum",
+                args: []
+            },
+        ],
+    },
+    {
+        name: "Luhn Checksum on standard data 2",
+        input: "896101950123440000",
+        expectedOutput: "Checksum: 5\n\nCheckdigit: 1\n\nLuhn Validated String: 8961019501234400001",
+        recipeConfig: [
+            {
+                op: "Luhn Checksum",
+                args: []
+            },
+        ],
+    },
+    {
+        name: "Luhn Checksum on standard data 3",
+        input: "35726908971331",
+        expectedOutput: "Checksum: 6\n\nCheckdigit: 7\n\nLuhn Validated String: 357269089713317",
         recipeConfig: [
             {
                 op: "Luhn Checksum",