From 8b96d09fa9b9810740e5c389cd6d39dc0ee2b02a Mon Sep 17 00:00:00 2001
From: xortiz <xavier.ortiz.ch@gmail.com>
Date: Mon, 1 Jan 2018 13:15:44 -0500
Subject: [PATCH] reduced repetition

Modified and created some functions within calculator.js that
would reduced repeated code. Also allowed written tests to run
as well as verify that they passed correctly.
---
 src/calculator.js      | 39 ++++++++++++---------------------------
 src/calculator.test.js |  2 +-
 2 files changed, 13 insertions(+), 28 deletions(-)

diff --git a/src/calculator.js b/src/calculator.js
index b46080e5..98af03f8 100644
--- a/src/calculator.js
+++ b/src/calculator.js
@@ -1,48 +1,33 @@
-exports._check = () => {
-  // DRY up the codebase with this function
-  // First, move the duplicate error checking code here
-  // Then, invoke this function inside each of the others
-  // HINT: you can invoke this function with exports._check()
+exports._check = (x, y) => {
+  exports._throwError(x);
+  exports._throwError(y);
 };
 
-exports.add = (x, y) => {
+exports._throwError = (x) => {
   if (typeof x !== 'number') {
     throw new TypeError(`${x} is not a number`);
   }
-  if (typeof y !== 'number') {
-    throw new TypeError(`${y} is not a number`);
-  }
+};
+
+exports.add = (x, y) => {
+  exports._check(x, y);
   return x + y;
 };
 
 exports.subtract = (x, y) => {
-  if (typeof x !== 'number') {
-    throw new TypeError(`${x} is not a number`);
-  }
-  if (typeof y !== 'number') {
-    throw new TypeError(`${y} is not a number`);
-  }
+  exports._check(x, y);
   return x - y;
 };
 
 exports.multiply = (x, y) => {
-  if (typeof x !== 'number') {
-    throw new TypeError(`${x} is not a number`);
-  }
-  if (typeof y !== 'number') {
-    throw new TypeError(`${y} is not a number`);
-  }
+  exports._check(x, y);
   return x * y;
 };
 
 exports.divide = (x, y) => {
-  if (typeof x !== 'number') {
-    throw new TypeError(`${x} is not a number`);
-  }
-  if (typeof y !== 'number') {
-    throw new TypeError(`${y} is not a number`);
-  }
+  exports._check(x, y);
   return x / y;
 };
 
 module.exports = exports;
+
diff --git a/src/calculator.test.js b/src/calculator.test.js
index d0f85ed6..3d6b7f74 100644
--- a/src/calculator.test.js
+++ b/src/calculator.test.js
@@ -1,7 +1,7 @@
 /* eslint-disable no-unused-expressions */
 const calculator = require('./calculator');
 
-describe.skip('_check', () => {
+describe('_check', () => {
   beforeEach(() => {
     sinon.spy(calculator, '_check');
   });