Add more explanation, add debugger, use expect

Fixes #13 (?)

Author: pletcher

README.md

@@ -182,6 +182,55 @@ if (conditionToTest1) {
 
 + Define a function `ageChecker` that takes in an age as a parameter. If the age is between 13-19 it should return `"You are a teenager!"`. If the age is 12 or below, it should return `"You are a kid"`. If the age is above 19, it should return `"You are a grownup"`
 
+**Top tip**: Remember, if you place a `return` statement before the end of the function, anything after `return` **won't get executed**. We can use this to make code terser:
+
+```javascript
+function canGo(lightColor) {
+  if (lightColor === 'green') {
+    return true
+  }
+
+  return false
+}
+```
+
+The above function will return `true` if `lightColor` is `'green'` — go ahead
+and try it out.
+
+```javascript
+canGo('green') // true
+```
+
+And `false` otherwise:
+
+```javascript
+canGo('red') // false
+```
+
+Notice that we didn't have to use an `else` statement; we can just depend on
+`return`.
+
+We need to be careful with `return`, however, because it's easy to return too
+early and not execute important parts of the function. For example,
+
+```javascript
+function canGo(lightColor) {
+  return true
+
+  if (lightColor === 'red') {
+    return false
+  }
+}
+```
+
+will _always_ return `true`, even if `lightColor` is `'red'`. Try it!
+
+```javascript
+canGo('red') // true
+```
+
+And that's a great way to cause an accident.
+
 ### Ternary Operator
 
 You can think of it as a shortcut for the `if-else` statement.
@@ -196,7 +245,6 @@ conditionToTest ? valueToBeReturnedIfTrue : valueToBeReturnedIfFalse
 
 + Define a function `ternaryTeenager` that accepts age as a parameter. The body of the function should use the ternary operator to return `"You are a teenager"` if age is between 13-19 and returns `"You are not a teenager"` if the age is anything else.
 
-
 ## Switch Statements
 
 Switch statements acts like a big if/else if/else chain. The switch expression is evaluated once and the value of the expression is compared with the values of each case. If there is a match, the associated block of code is executed.
@@ -220,7 +268,7 @@ Example:
 
 ```javascript
 var mood = "hungry"
-switch(mood){
+switch(mood) {
   case "happy":
     console.log("Dance to Pharrel's Happy");
     break;
@@ -242,6 +290,26 @@ In the example above, we'll see `"You should eat a big chocolate cake"` printed
 
 + Define a function `switchAge` that accepts an age as a parameter. The case statement should switch on `age` and return `"You are a teenager"` if the age is 13, 14, 15, 16, 17, 18, or 19, and return `"You have an age"` as the default.
 
+As with any function, `return` will halt execution at any point. Thus if we
+wrote,
+
+```javascript
+function feelings(mood) {
+  switch(mood) {
+    case "happy":
+      return "Dance to PHarrel's 'Happy'"
+    default:
+      return "I don't recognize that mood."
+  }
+
+  console.log("Let us know how you're feeling tomorrow!")
+}
+```
+
+the `console.log()` statement at the bottom of the function will
+_never run_. This is a major difference between `return` and `break`:
+`return` _exits_ the function and _returns_ a value; `break` exits a
+_block_ and does not (generally speaking) have a value associated with it.
 
 ## Resources
 

bin/debug-ide

@@ -0,0 +1,7 @@
+#!/bin/sh
+
+trap "trap - SIGTERM && kill -- -$$" SIGINT SIGTERM EXIT
+
+node_modules/.bin/node-inspector --hidden node_modules/ --hidden test/ --web-host $(/sbin/ifconfig eth0 | grep "inet addr" | awk -F: '{print $2}' | awk '{print $1}') --web-port $UID & node_modules/.bin/mocha --debug-brk --watch
+
+trap - SIGINT SIGTERM EXIT

flow-control.js

@@ -1,21 +1,19 @@
-'use strict';
-
-function basicTeenager(age){
+function basicTeenager(age) {
 
 }
 
-function teenager(age){
+function teenager(age) {
 
 }
 
-function ageChecker(age){
+function ageChecker(age) {
 
 }
 
-function ternaryTeenager(age){
+function ternaryTeenager(age) {
 
 }
 
-function switchAge(age){
+function switchAge(age) {
 
 }

package.json

@@ -7,6 +7,8 @@
     "test": "test"
   },
   "scripts": {
+    "debug": "node-debug --hidden node_modules _mocha --watch",
+    "debug-ide": "./bin/debug-ide",
     "test": "mocha -R mocha-multi --reporter-options nyan=-,json=.results.json"
   },
   "repository": {
@@ -26,10 +28,10 @@
   },
   "homepage": "https://github.com/learn-co-curriculum/skills-based-javascript-intro-to-flow-control#readme",
   "devDependencies": {
-    "chai": "^3.5.0",
+    "expect": "^1.20.2",
     "jsdom": "^8.5.0",
     "mocha": "^2.4.5",
-    "mocha-jsdom": "^1.1.0",
-    "mocha-multi": "^0.9.0"
+    "mocha-multi": "^0.9.0",
+    "node-inspector": "^0.12.8"
   }
 }

test/flow-control-test.js

@@ -1,70 +1,80 @@
-/*global describe, it */
-
-const expect = require('chai').expect
+const expect = require('expect')
 const fs = require('fs')
-const jsdom = require('mocha-jsdom')
+const jsdom = require('jsdom')
 const path = require('path')
 
 describe('flow-control', () => {
-  jsdom({
-    src: fs.readFileSync(path.resolve(__dirname, '..', 'flow-control.js'), 'utf-8')
+
+  before(done => {
+    const src = path.resolve(__dirname, '..', 'flow-control.js')
+
+    jsdom.env('<div></div>', [src], (err, window) => {
+      if (err) {
+        return done(err)
+      }
+
+      Object.keys(window).forEach(key => {
+        global[key] = window[key]
+      })
+
+      return done()
+    })
   })
 
   describe('basicTeenager', () => {
     it('should return "You are a teenager!" if the age is between 13-19', () => {
-      expect(basicTeenager(13)).to.equal("You are a teenager!");
+      expect(basicTeenager(13)).toEqual("You are a teenager!");
     })
 
     it('should return undefined if the age is not between 13-19', () => {
-      expect(basicTeenager(12)).to.be.undefined
+      expect(basicTeenager(12)).toBe(undefined)
     })
 
   })
 
   describe('teenager', () => {
     it('should return "You are a teenager!" if the age is between 13-19', () => {
-      expect(teenager(13)).to.equal("You are a teenager!")
+      expect(teenager(13)).toEqual("You are a teenager!")
     })
+
     it('should return "you are not a teenager" if the age is not between 13-19', () => {
-      expect(teenager(12)).to.equal("You are not a teenager")
-      expect(teenager(29)).to.equal("You are not a teenager")
+      expect(teenager(12)).toEqual("You are not a teenager")
+      expect(teenager(29)).toEqual("You are not a teenager")
     })
-
   })
 
   describe('ageChecker', () => {
     it('should return "You are a teenager!" if the age is between 13-19', () => {
-      expect(ageChecker(13)).to.equal("You are a teenager!")
+      expect(ageChecker(13)).toEqual("You are a teenager!")
     })
+
     it('should return "You are a kid" if the age is 12 or below', () => {
-      expect(ageChecker(12)).to.equal("You are a kid")
+      expect(ageChecker(12)).toEqual("You are a kid")
     })
+
     it('should return "You are a grownup" if the age is 20 or above', () => {
-      expect(ageChecker(29)).to.equal("You are a grownup")
+      expect(ageChecker(29)).toEqual("You are a grownup")
     })
-
   })
 
   describe('ternaryTeenager', () => {
     it('should return "You are a teenager" if age is between 13-19', () => {
-      expect(ternaryTeenager(15)).to.equal("You are a teenager")
+      expect(ternaryTeenager(15)).toEqual("You are a teenager")
     })
 
     it('should return "You are not a teenager" if age not between 13-19', () => {
-      expect(ternaryTeenager(75)).to.equal("You are not a teenager")
+      expect(ternaryTeenager(75)).toEqual("You are not a teenager")
     })
-
   })
 
   describe('switchAge', () => {
     it('should return "You are a teenager" if age is between 13-19', () => {
-      expect(switchAge(15)).to.equal("You are a teenager")
+      expect(switchAge(15)).toEqual("You are a teenager")
     })
 
     it('should return "You are not a teenager" if age not between 13-19', () => {
-      expect(switchAge(75)).to.equal("You have an age")
-      expect(switchAge(7)).to.equal("You have an age")
+      expect(switchAge(75)).toEqual("You have an age")
+      expect(switchAge(7)).toEqual("You have an age")
     })
-
   })
 })