Exceptions exercise

environment.md

@@ -8,52 +8,16 @@ In order to set yourself up for this course properly you are going to need a mac
 
 ## Setup your environment
 
-You are going to need administrator access to your laptop to install the software that we are going to use. With the help of the group facilitator you can make the request.
+ALl exercises should be done on your linux VDI. If you have don't have access to this contact someone who can help you.
 
-After you have got administrator rights you are going to need to do a few bits and pieces:
-
-* Register a Google Apps account to use Hangouts with
-* Install Slack and get an invite to the Sky or Sky Training team from your facilitator (we use this for most communication)
-* Install Google Chrome from the web (not Sky's self serve app store)
-* Install the Google Hangouts Chrome extension (we'll use this for video calling in the event we're working remotely)
-* Register for a Floobits account (Floobits is a really great service that will allow us to write code together)
-* Register a Github account (if you don't already have one)
-* Get access to Safari Books Online
-* Get access to Pluralsight
-* Get access to codeschool
-
-
-## Install Ruby
-
-To install Ruby we're going to use a tool called [`rbenv`](https://github.com/sstephenson/rbenv). To install this tool you can use [Homebrew](http://brew.sh/).
-
-For more information about installing this tool, [consult the readme](https://github.com/sstephenson/rbenv#homebrew-on-mac-os-x).
-
-The short version of this is:
-
-```
-# Install Homebrew
-
-ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"
-
-# Install rbenv
-
-brew update
-brew install rbenv ruby-build
-
-# Install a Ruby version
-
-rbenv install 2.2.3
-```
+You will need the following bits and pieces:
 
+* Access to Safari Books Online
+* Access to Pluralsight
 
 ## Checkout the bootcamp materials
 
-The [ruby-bootcamp](https://github.com/sky-uk/ruby-bootcamp) repository is the starting point for the bootcamp. You'll want to [fork the repository](https://github.com/sky-uk/ruby-bootcamp) and clone it locally. Start by reading the [readme](https://github.com/sky-uk/ruby-bootcamp/blob/master/readme.md).
+The [ruby-bootcamp](https://github.com/lvl-up/ruby-bootcamp-fil) repository is the starting point for the bootcamp. You'll want to clone it locally. Start by reading the [readme](https://github.com/lvl-up/ruby-bootcamp-fil/blob/master/readme.md).
 
-
-## Setup Floobits
-
-Floobits has a few features that require you to be authenticated against your account. Login in to Floobits and follow the instructions in under your settings area to create a .floorc.json in the home area of you VM.
-
-This step is optional as you may not require Floobits to pair with your facilitator (as they might be in the same room).
+## Install Ruby
+From the terminal, cd in to where you have checked out the bootcamp repo and run `./setup.sh`

exercises/exceptions/lib/cat.rb

@@ -0,0 +1,36 @@
+require_relative 'trick'
+
+class Cat
+  attr_reader :tricks
+
+  # This constructor takes named parameters, If you've not seen them before then
+  # have a read. They can be pretty useful and in the right circumstances can
+  # make your code more readable
+  def initialize(age:, name:)
+    @name = name
+    @age = age
+    @tricks = {divide: Trick::DIVISION}
+  end
+
+
+  def age_in_human_years
+    if @age > 2
+      25 + calculate_remaining_years(@age - 2)
+    else
+      calculate_remaining_years(@age)
+    end
+  end
+
+  def do_trick(name, *args)
+    tricks[name].call(*args)
+  end
+
+  def print_age_in_human_years
+    puts "I'm #{age_in_human_years} human years old"
+  end
+
+  private
+  def calculate_remaining_years age
+    age * 4
+  end
+end

exercises/exceptions/lib/trick.rb

@@ -0,0 +1,15 @@
+class Trick
+  attr_reader :trick
+  def initialize(&block)
+    @trick = block
+  end
+
+  def call(*args)
+    trick.call(*args)
+  end
+
+  DIVISION = Trick.new do |arg1, arg2|
+    arg1/arg2
+  end
+end
+

exercises/exceptions/readme.md

@@ -0,0 +1,52 @@
+# Exceptions
+
+
+## Introduction
+
+In this exercise you are going to write some exception handling code.
+
+## Exercise
+
+**_Note:_** You'll notice that there arn't any tests right now... Write them in order to add the new functionality required in the exercises that follow
+
+### 1. Raise an exception
+in [lib/cat.rb]('cat.rb') you'll find the `Cat` class. The constructor on this class requires you to set the age and name of the cat. However, this constructor could be more helpful than it is right now. Currently `Cat#initialize` will allow you to pass an age the is less than 0. This doesn't make much sense when thinking about cats and what's worse the `Cat#print_age_in_human_years` method just doesn't make sense when a negative age is used.
+
+```RUBY
+kitty = Cat.new(age: -1, name: 'billy')
+kitty.print_age_in_human_years #=> "I'm -4 human years old"
+```
+
+### 2. Raise a specific Exception
+Raising specific exceptions gives the user of your api the chance to make a choice about how they handle it.
+
+Modify the code in the constructor to raise an ArguementError and a helpful message if the age specified is less than 0. 
+
+```RUBY
+kitty = Cat.new(age: -1, name: 'billy') #=> ArgumentError"
+```
+
+### 3. Raise a Custom Error
+Having custom exception types can be exceptionally useful (excuse the pun).
+
+Define the method `Cat#learn_new_trick` that provides the signature utilised in the example below. If the cat is older than 100 in human years, throw a custom exception `ToBusySleepingError`
+
+```RUBY
+billy = Cat.new(name: 'billy', age: 2)
+billy.learn_new_trick(:answer_the_phone) do |args|
+  #code that performs the trick
+end
+
+billy.tricks #=> [:answer_the_phone]
+
+bob = Cat.new(name: 'bob', age: 35)
+bob.learn_new_trick(:answer_the_phone) #> Raises ToBusySleepingError
+``` 
+
+### 4. Catch an Error
+The cats built using the`Cat` are pretty clever. They know how to divide numbers! Problem is they don't know what to do when the second of those numbers is 0... Enhance the code for the skill to catch the divide by 0 error when if it happens and return nil instead.
+
+```RUBY
+billy = Cat.new(name: 'billy', age: 2)
+billy.do_trick(:divide, 5,0) # => should return 0
+```

exercises/run-ruby/readme.md

@@ -32,4 +32,4 @@ Use `irb` to run some of the statements in [runme.rb](runme.rb):
 
 * What sort of object do you get when you run `Time.now`. (Use the `.class` method to find out)
 * What other methods does that returned object have on it? (use the `.public_methods` method to find out, e.g. `Time.now.public_methods`)
-* Use the Time RDoc to find out what extras you get
+* Use the [Time RDoc](https://ruby-doc.org/stdlib-2.3.1/libdoc/time/rdoc/Time.html) to find out what extras you get

setup.sh

@@ -0,0 +1,52 @@
+#!/bin/bash
+
+PROFILELINE='export PATH=$PATH:/$HOME/.rvm/bin && [[ -s "$HOME/.rvm/scripts/rvm" ]] && source "$HOME/.rvm/scripts/rvm" # Load RVM into a shell session *as a function*'
+
+
+PROFILEFILE=~/.profile
+BASHRCLINE="source $PROFILEFILE"
+BASHRCFILE=~/.bashrc
+RUBYVERSION=2.3
+
+checkerror () {
+        RC=$?
+        if [ $RC -ne 0 ]; then
+                echo "ERROR: $*"
+        fi
+}
+
+echo "Installing gpg key"
+gpg --keyserver hkp://keys.gnupg.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3 7D2BAF1CF37B13E2069D6956105BD0E739499BDB
+checkerror "Unable to install GPG key required to install RVM"
+
+\curl -sSL https://raw.githubusercontent.com/wayneeseguin/rvm/stable/binscripts/rvm-installer | bash -s stable 
+checkerror "Unable io install RVM"
+
+source $PROFILEFILE
+checkerror "Unable to source profile file"
+
+echo "Installing Ruby - enter corporate password when prompted"
+rvm install ruby-$RUBYVERSION
+checkerror "Unable to install Ruby version $RUBYVERSION"
+
+
+grep -qF "$PROFILELINE" "$PROFILEFILE" || echo "$PROFILELINE" >> "$PROFILEFILE"
+checkerror "Unable to add $PROFILELINE to $PROFILEFILE"
+
+source $PROFILEFILE
+checkerror "Unable to source profile file"
+
+if [[ -f $BASHRCFILE ]]; then
+    grep -qF "$BASHRCLINE" "$BASHRCFILE" || echo "$BASHRCLINE" >> "$BASHRCFILE"
+    checkerror "Unable to add $BASHRCLINE to $BASHRCFILE"
+else
+    echo "Unable to locate the bashrc file $BASHRCFILE"
+    exit 1
+fi
+
+
+source $PROFILEFILE
+checkerror "Unable to source profile file"
+
+rvm --default use $RUBYVERSION
+checkerror "Unable to set the default version of ruby within RVM to $RUBYVERSION"