From 2b7b3d6e2fd87cfa3fc620aa0b51db399ed5a14b Mon Sep 17 00:00:00 2001
From: Rachel Moser <moser.rachel@gmail.com>
Date: Sun, 19 Sep 2021 17:28:17 -0500
Subject: [PATCH 1/2] Feature: Add testing exercises for RSpec lessons

Because:
* The new RSpec testing lessons needs corresponding exercises.

This Commit:
* Adds 5 RSpec Matcher exercises for Testing Basics lesson.
* Adds 2 RSpec exercises for Testing Part 2 lesson.
* Updates RSpec version.
* Adds rubocop, but ignores the ruby_basics directory.
* Adds README for the ruby_testing directory.
---
 .rubocop.yml                                  |  6 ++
 Gemfile                                       |  5 +-
 Gemfile.lock                                  | 45 ++++++++---
 ruby_testing/1_rspec_basics/.rspec            |  1 +
 .../1_rspec_basics/spec/1_eq_matcher_spec.rb  | 16 ++++
 .../spec/2_include_matcher_spec.rb            | 19 +++++
 .../spec/3_be_true_false_spec.rb              | 35 ++++++++
 .../spec/4_be_nil_matcher_spec.rb             | 18 +++++
 .../spec/5_contain_exactly_spec.rb            | 15 ++++
 .../1_rspec_basics/spec/spec_helper.rb        | 19 +++++
 ruby_testing/2_rspec_techniques/.rspec        |  1 +
 .../spec/1_equality_matchers_spec.rb          | 62 +++++++++++++++
 .../spec/2_lesson_practice_spec.rb            | 79 +++++++++++++++++++
 .../2_rspec_techniques/spec/spec_helper.rb    | 19 +++++
 ruby_testing/README.md                        | 27 +++++++
 15 files changed, 354 insertions(+), 13 deletions(-)
 create mode 100644 .rubocop.yml
 create mode 100644 ruby_testing/1_rspec_basics/.rspec
 create mode 100644 ruby_testing/1_rspec_basics/spec/1_eq_matcher_spec.rb
 create mode 100644 ruby_testing/1_rspec_basics/spec/2_include_matcher_spec.rb
 create mode 100644 ruby_testing/1_rspec_basics/spec/3_be_true_false_spec.rb
 create mode 100644 ruby_testing/1_rspec_basics/spec/4_be_nil_matcher_spec.rb
 create mode 100644 ruby_testing/1_rspec_basics/spec/5_contain_exactly_spec.rb
 create mode 100644 ruby_testing/1_rspec_basics/spec/spec_helper.rb
 create mode 100644 ruby_testing/2_rspec_techniques/.rspec
 create mode 100644 ruby_testing/2_rspec_techniques/spec/1_equality_matchers_spec.rb
 create mode 100644 ruby_testing/2_rspec_techniques/spec/2_lesson_practice_spec.rb
 create mode 100644 ruby_testing/2_rspec_techniques/spec/spec_helper.rb
 create mode 100644 ruby_testing/README.md

diff --git a/.rubocop.yml b/.rubocop.yml
new file mode 100644
index 0000000000..f3495a234c
--- /dev/null
+++ b/.rubocop.yml
@@ -0,0 +1,6 @@
+AllCops:
+  NewCops: enable
+  Exclude:
+    - 'ruby_basics/**/*'
+Style/Documentation:
+  Enabled: false
diff --git a/Gemfile b/Gemfile
index bc63d8fb1f..b7710cd9f8 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,3 +1,6 @@
+# frozen_string_literal: true
+
 source 'https://rubygems.org'
 
-gem 'rspec', '~>3.9'
\ No newline at end of file
+gem 'rspec', '~> 3.10'
+gem 'rubocop', '~> 1.21'
diff --git a/Gemfile.lock b/Gemfile.lock
index bbce5c370e..b0a2d69f64 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,26 +1,47 @@
 GEM
   remote: https://rubygems.org/
   specs:
+    ast (2.4.2)
     diff-lcs (1.4.4)
-    rspec (3.9.0)
-      rspec-core (~> 3.9.0)
-      rspec-expectations (~> 3.9.0)
-      rspec-mocks (~> 3.9.0)
-    rspec-core (3.9.2)
-      rspec-support (~> 3.9.3)
-    rspec-expectations (3.9.2)
+    parallel (1.21.0)
+    parser (3.0.2.0)
+      ast (~> 2.4.1)
+    rainbow (3.0.0)
+    regexp_parser (2.1.1)
+    rexml (3.2.5)
+    rspec (3.10.0)
+      rspec-core (~> 3.10.0)
+      rspec-expectations (~> 3.10.0)
+      rspec-mocks (~> 3.10.0)
+    rspec-core (3.10.1)
+      rspec-support (~> 3.10.0)
+    rspec-expectations (3.10.1)
       diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.9.0)
-    rspec-mocks (3.9.1)
+      rspec-support (~> 3.10.0)
+    rspec-mocks (3.10.2)
       diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.9.0)
-    rspec-support (3.9.3)
+      rspec-support (~> 3.10.0)
+    rspec-support (3.10.2)
+    rubocop (1.21.0)
+      parallel (~> 1.10)
+      parser (>= 3.0.0.0)
+      rainbow (>= 2.2.2, < 4.0)
+      regexp_parser (>= 1.8, < 3.0)
+      rexml
+      rubocop-ast (>= 1.9.1, < 2.0)
+      ruby-progressbar (~> 1.7)
+      unicode-display_width (>= 1.4.0, < 3.0)
+    rubocop-ast (1.11.0)
+      parser (>= 3.0.1.1)
+    ruby-progressbar (1.11.0)
+    unicode-display_width (2.1.0)
 
 PLATFORMS
   ruby
 
 DEPENDENCIES
-  rspec (~> 3.9)
+  rspec (~> 3.10)
+  rubocop (~> 1.21)
 
 BUNDLED WITH
    2.1.4
diff --git a/ruby_testing/1_rspec_basics/.rspec b/ruby_testing/1_rspec_basics/.rspec
new file mode 100644
index 0000000000..279bfd9e99
--- /dev/null
+++ b/ruby_testing/1_rspec_basics/.rspec
@@ -0,0 +1 @@
+--require spec_helper --format documentation --color
diff --git a/ruby_testing/1_rspec_basics/spec/1_eq_matcher_spec.rb b/ruby_testing/1_rspec_basics/spec/1_eq_matcher_spec.rb
new file mode 100644
index 0000000000..deef7bc991
--- /dev/null
+++ b/ruby_testing/1_rspec_basics/spec/1_eq_matcher_spec.rb
@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+def generate_hashtag(str)
+  tag = str.split.map(&:capitalize).join
+  return nil unless tag.length.between?(1, 139)
+
+  "##{tag}"
+end
+
+RSpec.describe 'Eq Matcher Exercise' do
+  # Write a test that generate_hashtag('The Odin Project') eq '#TheOdinProject'
+
+  # Write a test that generate_hashtag('Ruby on Rails') eq '#RubyOnRails'
+
+  # Write a test that generate_hashtag('Join our Discord Community') eq '#JoinOurDiscordCommunity'
+end
diff --git a/ruby_testing/1_rspec_basics/spec/2_include_matcher_spec.rb b/ruby_testing/1_rspec_basics/spec/2_include_matcher_spec.rb
new file mode 100644
index 0000000000..8b0a6d4d39
--- /dev/null
+++ b/ruby_testing/1_rspec_basics/spec/2_include_matcher_spec.rb
@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+def create_range(min, max)
+  (min..max).to_a
+end
+
+RSpec.describe 'Include Matcher Exercises' do
+  # Write a test that create_range(0, 5) includes 0, 1, 2, 3, 4, 5
+
+  # Write a test that create_range(0, 5) includes 3
+
+  # Write a test that create_range(0, 5) does not include 11
+
+  # Write a test that create_range(5, 10) includes 5, 6, 7, 8, 9, 10
+
+  # Write a test that create_range(5, 10) includes 5, 7, 9
+
+  # Write a test that create_range(5, 10) does not include 0 or 1
+end
diff --git a/ruby_testing/1_rspec_basics/spec/3_be_true_false_spec.rb b/ruby_testing/1_rspec_basics/spec/3_be_true_false_spec.rb
new file mode 100644
index 0000000000..ed0c9d4d6e
--- /dev/null
+++ b/ruby_testing/1_rspec_basics/spec/3_be_true_false_spec.rb
@@ -0,0 +1,35 @@
+# frozen_string_literal: true
+
+RSpec.describe 'Be True False Matcher Exercises' do
+  describe 'be truthy and falsy matcher' do
+    # Using the be matcher, write a test that any string, for example 'hello' is truthy
+
+    # Using the be matcher, write a test that any number, for example -100 is truthy
+
+    # Using the be matcher, write a test that any array, for example [] is truthy
+
+    # Using the be matcher, write a test that true is truthy
+
+    # Using the be matcher, write a test that false is falsy
+
+    # Using the be matcher, write a test that nil is falsy
+  end
+
+  # As you can see, almost all values are truthy, with the exception of false and nil.
+  # Therefore do not use 'be_truthy' or 'be_falsy' for methods that should only be evaluated into a Boolean.
+  # https://eddyluten.com/rspec-be_truthy-exists-or-be-true
+
+  def palindrome?(word)
+    word.reverse == word
+  end
+
+  describe 'be true and false matcher' do
+    # Using the be matcher, write a test that palindrome?('cat') is false
+
+    # Using the be matcher, write a test that palindrome?('level') is true
+
+    # Using the be matcher, write a test that palindrome?('racecar') is true
+
+    # Using the be matcher, write a test that palindrome?('odin') is false
+  end
+end
diff --git a/ruby_testing/1_rspec_basics/spec/4_be_nil_matcher_spec.rb b/ruby_testing/1_rspec_basics/spec/4_be_nil_matcher_spec.rb
new file mode 100644
index 0000000000..c32df245e5
--- /dev/null
+++ b/ruby_testing/1_rspec_basics/spec/4_be_nil_matcher_spec.rb
@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+def generate_hashtag(str)
+  tag = str.split.map(&:capitalize).join
+  return nil unless tag.length.between?(1, 139)
+
+  "##{tag}"
+end
+
+RSpec.describe 'Be Nil Matcher Exercises' do
+  # Using the be matcher, write a test that generate_hashtag('') is nil
+
+  # Using the be matcher, write a test that generate_hashtag('a' * 140) is nil
+
+  # Using the be matcher, write a test that generate_hashtag(' ' * 140) is nil
+
+  # Using the be matcher, write a test that generate_hashtag('The Odin Proejct') is not nil
+end
diff --git a/ruby_testing/1_rspec_basics/spec/5_contain_exactly_spec.rb b/ruby_testing/1_rspec_basics/spec/5_contain_exactly_spec.rb
new file mode 100644
index 0000000000..3a2e4bc37f
--- /dev/null
+++ b/ruby_testing/1_rspec_basics/spec/5_contain_exactly_spec.rb
@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+def create_range(min, max)
+  (min..max).to_a
+end
+
+RSpec.describe 'Contain Exactly Matcher Exercises' do
+  # Write a test that create_range(0, 3) contains exactly 0, 1, 2, 3
+
+  # Write a test that create_range(0, 3) contains exactly 3, 2, 1, 0
+
+  # Write a test that create_range(0, 3)) contains exactly 1, 3, 0, 2
+
+  # Write a test that create_range(0, 3) contains exactly 2, 0, 3, 1
+end
diff --git a/ruby_testing/1_rspec_basics/spec/spec_helper.rb b/ruby_testing/1_rspec_basics/spec/spec_helper.rb
new file mode 100644
index 0000000000..eb06f2502e
--- /dev/null
+++ b/ruby_testing/1_rspec_basics/spec/spec_helper.rb
@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+RSpec.configure do |config|
+  config.expect_with :rspec do |expectations|
+    expectations.include_chain_clauses_in_custom_matcher_descriptions = true
+  end
+
+  config.mock_with :rspec do |mocks|
+    mocks.verify_partial_doubles = true
+  end
+
+  config.shared_context_metadata_behavior = :apply_to_host_groups
+end
+
+module FormatterOverrides
+  def dump_pending(_); end
+end
+
+RSpec::Core::Formatters::DocumentationFormatter.prepend FormatterOverrides
diff --git a/ruby_testing/2_rspec_techniques/.rspec b/ruby_testing/2_rspec_techniques/.rspec
new file mode 100644
index 0000000000..279bfd9e99
--- /dev/null
+++ b/ruby_testing/2_rspec_techniques/.rspec
@@ -0,0 +1 @@
+--require spec_helper --format documentation --color
diff --git a/ruby_testing/2_rspec_techniques/spec/1_equality_matchers_spec.rb b/ruby_testing/2_rspec_techniques/spec/1_equality_matchers_spec.rb
new file mode 100644
index 0000000000..94086dec3a
--- /dev/null
+++ b/ruby_testing/2_rspec_techniques/spec/1_equality_matchers_spec.rb
@@ -0,0 +1,62 @@
+# frozen_string_literal: true
+
+RSpec.describe 'Equality Matcher Exercises' do
+  describe 'eq and eql (equality matchers)' do
+    let(:my_score) { 10.0 } # Float
+    let(:your_score) { 10 } # Integer
+
+    context 'when using eq matcher' do
+      # NOTE: the eq matcher looks at the VALUE of the objects.
+
+      # Using the eq matcher, test that my_score is eq to your_score
+    end
+
+    context 'when using eql matcher' do
+      # NOTE: the eql matcher looks at the VALUE and the TYPE of the objects.
+
+      # Temporarily remove the 'x' from the following test, run this test, and read the error message.
+      # It fails because my_score and your_score do not have eql VALUE and TYPE.
+      xit 'has eql value and type' do
+        expect(my_score).to eql(your_score)
+      end
+
+      # Using the eql matcher, test that my_score is not eql to your_score
+    end
+  end
+
+  describe 'eql, equal, and be (equality matchers)' do
+    let(:my_car) { { year: 2013, make: 'Toyota', model: 'Camry' } }
+    let(:your_car) { { year: 2013, make: 'Toyota', model: 'Camry' } }
+    let(:my_kids_borrowed_car) { my_car }
+
+    context 'when using eql matcher' do
+      # Using the eql matcher, test that my_car is eql to your_car
+
+      # Using the eql matcher, test that my_kids_borrowed_car is eql to your_car
+    end
+
+    # Wait a second... my kids can borrow your car!?!
+
+    context 'when using equal matcher' do
+      # NOTE: the equal matcher looks at the OBJECT IDENTITY.
+
+      # Temporarily remove the 'x' from the following test, run this test, and read the error message.
+      # It fails because my_kids_borrowed_car and your_car do not have the same OBJECT IDENTITY.
+      xit 'has object identity' do
+        expect(my_kids_borrowed_car).to equal(your_car)
+      end
+
+      # Using the equal matcher, test that my_kids_borrowed_car is not equal to your_car
+    end
+
+    # Whew! I bet you're relieved that my kids can not borrow your car anymore!
+
+    context 'when using be matcher' do
+      # NOTE: the be matcher is similar to the equal matcher (looks at the OBJECT IDENTITY).
+
+      # Using the be matcher, test that my_kids_borrowed_car is my_car
+
+      # Using the be matcher, test that my_kids_borrowed_car is not your_car
+    end
+  end
+end
diff --git a/ruby_testing/2_rspec_techniques/spec/2_lesson_practice_spec.rb b/ruby_testing/2_rspec_techniques/spec/2_lesson_practice_spec.rb
new file mode 100644
index 0000000000..38d78dc40d
--- /dev/null
+++ b/ruby_testing/2_rspec_techniques/spec/2_lesson_practice_spec.rb
@@ -0,0 +1,79 @@
+# frozen_string_literal: true
+
+# In a typical workflow, the class being tested will be located in a separate file from the tests.
+# However, for this simple example, we are going to keep everything together.
+
+class SchoolClub
+  attr_reader :count, :members
+
+  def initialize(name, members = [])
+    @name = name
+    @members = members
+    @count = members.length
+  end
+
+  def add_members(*names)
+    names.each do |name|
+      @members << name
+      @count += 1
+    end
+  end
+
+  def remove_members(*names)
+    names.each do |name|
+      next unless @members.include?(name)
+
+      @members.delete(name)
+      @count -= 1
+    end
+  end
+end
+
+RSpec.describe SchoolClub do
+  # Create a named subject with just a club name, for example SchoolClub.new('Robotics Club')
+
+  describe 'add_members' do
+    context 'when adding one new member' do
+      # Using a before block, add one member to the club. For example, robotics_club.add_members('Adam')
+
+      # Test the value of count, for example that robotics_club.count is 1
+
+      # Test the value of members, for example that robotics_club.members includes Adam
+    end
+
+    context 'when adding three new members' do
+      # Using a before block, add three members to the club.
+      # For example, robotics_club.add_members('Alice', 'Bob', 'Carrie')
+
+      # Test the value of count, for example that robotics_club.count is 3
+
+      # Test the value of members, for example that robotics_club.members includes Alice, Bob, and Carrie
+    end
+  end
+
+  describe 'remove_members' do
+    # Create a named subject with a club name and a founders variable that we will define in each context.
+    # For example SchoolClub.new('Chess Club', founders)
+
+    context 'when removing one member from two member club' do
+      # Create a let variable named founders that is an array with two names, for example, ['Adam', 'Beth']
+
+      # Using a before block, remove one member from the club. For example, chess_club.remove_members('Beth')
+
+      # Test the value of count, for example that chess_club.count is 1
+
+      # Test the value of members, for example that chess_club.members does not include Beth
+    end
+
+    context 'when removing two members from four member club' do
+      # Create another let variable named founders that is an array with four names.
+      # For example, ['Alice', 'Bob', 'Carrie', 'Dave']
+
+      # Using a before block, remove two members from the club. For example, chess_club.remove_members('Carrie', 'Dave')
+
+      # Test the value of count, for example that chess_club.count is 2
+
+      # Test the value of members, for example that chess_club.members does not include Carrie or Dave
+    end
+  end
+end
diff --git a/ruby_testing/2_rspec_techniques/spec/spec_helper.rb b/ruby_testing/2_rspec_techniques/spec/spec_helper.rb
new file mode 100644
index 0000000000..eb06f2502e
--- /dev/null
+++ b/ruby_testing/2_rspec_techniques/spec/spec_helper.rb
@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+RSpec.configure do |config|
+  config.expect_with :rspec do |expectations|
+    expectations.include_chain_clauses_in_custom_matcher_descriptions = true
+  end
+
+  config.mock_with :rspec do |mocks|
+    mocks.verify_partial_doubles = true
+  end
+
+  config.shared_context_metadata_behavior = :apply_to_host_groups
+end
+
+module FormatterOverrides
+  def dump_pending(_); end
+end
+
+RSpec::Core::Formatters::DocumentationFormatter.prepend FormatterOverrides
diff --git a/ruby_testing/README.md b/ruby_testing/README.md
new file mode 100644
index 0000000000..019b20debe
--- /dev/null
+++ b/ruby_testing/README.md
@@ -0,0 +1,27 @@
+# Ruby Testing Exercises
+These exercises are designed to compliment the Ruby Testing lessons from [The Odin Project](https://www.theodinproject.com/).
+
+### Usage
+
+1. Navigate to a lesson directory, for example `cd ruby_testing/1_rspec_basics`.
+2. Run the tests for the first exercise file, for example `bundle exec rspec spec/1_eq_matcher_spec.rb. **No examples should be found, because it is your turn to write the tests!**
+3. Open the exercise spec file in your text editor.
+4. Follow the instructions in the file to write **one** test.
+5. Run the tests again to verify it passes before moving on to the next test.
+6. Repeat steps 4 and 5, until you written all tests in a file.
+7. If there are additional exercise spec files in the lesson directory, repeat steps 1-6 for each file.
+
+###  Contents
+
+#### 1. RSpec - The Basics
+
+- [ ] Eq Matcher Exercises
+- [ ] Include Matcher Exercises
+- [ ] Be True/False Matcher Exercises
+- [ ] Be Nil Matcher Exercises
+- [ ] Contain Exactly Matcher Exercises
+
+#### 2. RSpec - Hooks, Let and Subject
+
+- [ ] Equality Matcher Exercises
+- [ ] Lesson Practice Exercises

From 0abb084d6920fa1031cc5aebe5077cb07b17a38b Mon Sep 17 00:00:00 2001
From: Rachel Moser <moser.rachel@gmail.com>
Date: Sun, 19 Sep 2021 22:15:47 -0500
Subject: [PATCH 2/2] Fix a few minor typos

---
 ruby_basics/README.md                                      | 2 +-
 ruby_testing/1_rspec_basics/spec/4_be_nil_matcher_spec.rb  | 2 +-
 ruby_testing/1_rspec_basics/spec/5_contain_exactly_spec.rb | 2 +-
 ruby_testing/README.md                                     | 4 ++--
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/ruby_basics/README.md b/ruby_basics/README.md
index 86d72227e4..0b3ee5a477 100644
--- a/ruby_basics/README.md
+++ b/ruby_basics/README.md
@@ -1,5 +1,5 @@
 # Ruby Basics Exercises
-These exercises are designed to compliment the [Ruby Basic lessons](https://www.theodinproject.com/courses/ruby-programming#basic-ruby) on [The Odin Project](https://www.theodinproject.com/). Each folder contains exercises and specs(tests) for the lessons in the Ruby Basics section.
+These exercises are designed to complement the [Ruby Basic lessons](https://www.theodinproject.com/courses/ruby-programming#basic-ruby) on [The Odin Project](https://www.theodinproject.com/). Each folder contains exercises and specs(tests) for the lessons in the Ruby Basics section.
 
 ### Usage
 
diff --git a/ruby_testing/1_rspec_basics/spec/4_be_nil_matcher_spec.rb b/ruby_testing/1_rspec_basics/spec/4_be_nil_matcher_spec.rb
index c32df245e5..0c29b9d2ff 100644
--- a/ruby_testing/1_rspec_basics/spec/4_be_nil_matcher_spec.rb
+++ b/ruby_testing/1_rspec_basics/spec/4_be_nil_matcher_spec.rb
@@ -14,5 +14,5 @@ def generate_hashtag(str)
 
   # Using the be matcher, write a test that generate_hashtag(' ' * 140) is nil
 
-  # Using the be matcher, write a test that generate_hashtag('The Odin Proejct') is not nil
+  # Using the be matcher, write a test that generate_hashtag('The Odin Project') is not nil
 end
diff --git a/ruby_testing/1_rspec_basics/spec/5_contain_exactly_spec.rb b/ruby_testing/1_rspec_basics/spec/5_contain_exactly_spec.rb
index 3a2e4bc37f..5652b9ae77 100644
--- a/ruby_testing/1_rspec_basics/spec/5_contain_exactly_spec.rb
+++ b/ruby_testing/1_rspec_basics/spec/5_contain_exactly_spec.rb
@@ -9,7 +9,7 @@ def create_range(min, max)
 
   # Write a test that create_range(0, 3) contains exactly 3, 2, 1, 0
 
-  # Write a test that create_range(0, 3)) contains exactly 1, 3, 0, 2
+  # Write a test that create_range(0, 3) contains exactly 1, 3, 0, 2
 
   # Write a test that create_range(0, 3) contains exactly 2, 0, 3, 1
 end
diff --git a/ruby_testing/README.md b/ruby_testing/README.md
index 019b20debe..be86c8689a 100644
--- a/ruby_testing/README.md
+++ b/ruby_testing/README.md
@@ -1,10 +1,10 @@
 # Ruby Testing Exercises
-These exercises are designed to compliment the Ruby Testing lessons from [The Odin Project](https://www.theodinproject.com/).
+These exercises are designed to complement the Ruby Testing lessons from [The Odin Project](https://www.theodinproject.com/).
 
 ### Usage
 
 1. Navigate to a lesson directory, for example `cd ruby_testing/1_rspec_basics`.
-2. Run the tests for the first exercise file, for example `bundle exec rspec spec/1_eq_matcher_spec.rb. **No examples should be found, because it is your turn to write the tests!**
+2. Run the tests for the first exercise file, for example `bundle exec rspec spec/1_eq_matcher_spec.rb`. **No examples should be found, because it is your turn to write the tests!**
 3. Open the exercise spec file in your text editor.
 4. Follow the instructions in the file to write **one** test.
 5. Run the tests again to verify it passes before moving on to the next test.