Ex1

ex1/ex1.js

@@ -6,3 +6,21 @@
  *     fn(",,,") === 2
  *     fn("hel,lowo,rld") === -1
  */
+
+function getThirdCommaIndex(str,searchFor) {
+
+        var index = -1;
+
+	for (var i = 0; i < 3; i++) {
+
+		index = str.indexOf(searchFor, index + 1);
+
+		//  If we did not find a comma in str will stop searching
+		if (index == -1) { 
+			break;
+		}
+	}
+	return index;
+}
+
+module.exports = getThirdCommaIndex;

ex1/ex1Spec.js

@@ -0,0 +1,19 @@
+var getThirdCommaIndex = require("./ex1");
+
+describe("function getThirdCommaIndex", function() {
+
+	it("returns -1 when no third comma", function() {
+		expect(getThirdCommaIndex('hel,lowo,rld', ','))
+		.toBe(-1);
+	});
+
+	it("finds a comma in a regular sentence", function() {
+		expect(getThirdCommaIndex('hello,world,this,is,a,great,day', ','))
+		.toBe(16);
+	});
+
+	it("works even when there are no characters beside commas", function() {
+		expect(getThirdCommaIndex(',,,', ','))
+		.toBe(2);
+	});
+});