added solutions to sum.js in implement

Author: Alex Jamshidi

Sprint-1/implement/sum.js

@@ -1,5 +1,8 @@
 function sum(list) {
-    return 0
+    const numbers = list.filter(n => Number.isFinite(n));
+    let total = 0;
+    for (n of numbers) {total += n};
+    return total;
 }
 
 module.exports = sum;

Sprint-1/implement/sum.test.js

@@ -50,16 +50,16 @@ describe("sum", () => {
 // Then it should ignore the non-numerical values and return the sum of the numerical elements
 
   it("array with non-number values returns sum of numerical values only", () => {
-    const list = [1];
-    expect(sum(list)).toEqual(1);
+    const list = [1, 2, "apple", 4, "banana", 3];
+    expect(sum(list)).toEqual(10);
   });
 
 // Given an array with only non-number values
 // When passed to the sum function
 // Then it should return the least surprising value given how it behaves for all other inputs
 
   it("array with non-number values only returns least surprising output", () => {
-    const list = [1];
+    const list = ["a", "b", "c"];
     expect(sum(list)).toEqual(0);
   });
 });