sf-wdi-25/ruby_method_drills

32 ruby methods with tests

Ruby Method Drills

Can you write code in drills.rb to pass the tests in the spec folder?

Setup

Fork this repo on GitHub.

git clone YOUR_FORK_CLONE_URL.git
cd ruby_method_drills

Testing

We'll use a tool called rspec to outline our objectives AND test our code as we go... hooray for Test Driven Development (TDD)!

rspec is available as a Ruby gem, so start in your terminal by running the command:

    gem install rspec

You might get an error here, but we believe in you. Fix it.

Test Driven Development -- "Red, Green, Refactor"

Take a look at one of the "spec" files in the spec/ folder. These are the tests that we want to make pass.

To run all the tests type the following in the command line:

    rspec
    # or run a specific spec file
    rspec spec/1_argument_spec.rb

You should see roughly the following output:

FFFFFFFF ---> 8 failed tests ("F"), 0 passed tests (".")
Failures:

  1) #say_hello returns 'hello'
     Failure/Error: expect( say_hello ).to eq "hello"
       
       expected: "hello"
            got: "hi"
       
       (compared using ==)
     # ./spec/drills_spec.rb:8:in `block (2 levels) in <top (required)>'

Finished in 0.0028 seconds (files took 0.08831 seconds to load)
8 examples, 8 failures

Failed examples:
rspec ./spec/drills_spec.rb:7 # #say_hello returns 'hello'

Congrats!

• The first tests are failing. We're seeing RED.
• Now we need to write code (in drills.rb) to pass the tests and turn them GREEN.
• When the test passes, we're ready to stop and REFACTOR!

Rspec Tips

• Pay close attention to the rspec output in your terminal
• Run your tests frequently and read the output carefully.
• BE VERY CAREFUL to use the correct function name.
• To limit your test output, consider filtering tests by method name:

    rspec spec/1_argument_spec.rb -e get_fruit

Ruby Tips

When in doubt, test your code in the ruby REPL (irb, interactive ruby):

    irb

(This is similar to running the node repl by typing node).

When you want to quit irb, enter quit.

Inside irb you can "hang a dot" and hit tab twice to see available methods:

    2.1.2 :001 > "string". # hang a dot and hit tab twice!
    # Display all 148 possibilities? (y or n)
    #                               "".match
    # "".__id__                      "".method
    # "".__send__                    "".methods
    # "".ascii_only?                 "".next
    # "".b                           "".next!
    # "".between?                    "".nil?
    # "".bytes                       "".object_id
    # "".bytesize                    "".oct
    # ...

Another handy trick is to load your drills.rb file so that you can manually test your functions. This is similar to what we did in node when we used "require" to import a file.

Make sure you're in the correct directory, then in irb type:

    2.1.2 :002 > load "./drills.rb"
    2.1.2 :003 > say_hello

You can also run a ruby file from the command line by typing:

    ruby drills.rb