RSpec for Practical Rubyist

@ RubyConfTaiwan 2015

Transcript

1. RSPEC
   FOR THE
   PRACTICAL RUBYIST
   EXPLAINING SIMPLY AND QUICKLY
   ALL THE ELEMENTS OF
   CONTROLLER, MODEL, VIEW,
   HELPER, INTEGRATION, FEATURE
   WITHout
   ANSWERS TO PROBLEMS
   

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2. 2015!!!
   RubyConFTW
   

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3. rubytaiwan/taipei
   Things to know about Taipei put together by
   Ruby Taiwan Community
   Inspired from RubySG/Singapore
   

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4. Juanito Fatas
   !
   

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5. juanitofatas/fast-ruby
   Collection of Idioms, Benchmarks, etc. for Faster Ruby Code
   Inspired by @sferik and Ruby Community
   

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6. Employee #1
   

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7. The Birth of deppbot
   

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8. JuanitoFatas/rubygems.org/pull/1
   

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12. JOIN
    OPEN
    SOURCE
    

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13. Tweet at Me
    @juanitofatas
    "
    #rubyconFTW
    #rubyconFTW2015
    

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15. Introducing
    4K
    Live Photos
    iPhone 6S Plus
    

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16. muan/mojibar
    

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17. Emoji is
    Awesome!
    

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18. 95% of time
    preparations
    of this talk
    

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19. Tweak fonts and
    think about emojis
    

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20. First of all
    

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21. It’s been a
    tough day
    

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22. %
    

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24. Some
    mathematics
    
    

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25. My first talk ever,
    5-minute long ⏳
    

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26. My second talk,
    50-minute long
    
    

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27. Let ψ = 5
    

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28. Let ω = 50
    

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29. ω
    —
    ψ
    =
    

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30. 50
    —
    ψ
    =
    

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31. 50
    —
    5
    =
    

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32. 50
    —
    5
    =10
    

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33. ∴
    

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34. I am a
    10x
    Speaker
    
    

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35. Q.E.D.
    

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36. Matz is
    Great!
    ,,,,,,
    

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37. Talk Title
    Origin
    

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38. Richard Feynman
    

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40. RSPEC
    FOR THE
    PRACTICAL RUBYIST
    EXPLAINING SIMPLY AND QUICKLY
    ALL THE ELEMENTS OF
    CONTROLLER, MODEL, VIEW,
    HELPER, INTEGRATION, FEATURE
    WITHout
    ANSWERS TO PROBLEMS
    

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41. Why This Talk
    

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42. Rubyists in Taiwan
    are courageous.
    

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44. Raise the awareness
    of Testing in Thiland
    

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45. Journey into
    Rails Testing
    ⛵0
    

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46. Introductory Talk
    No theory, and TDD because
    How-to, but not what & why
    Tutorial type
    
    
    
    
    

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47. Just Enough
    Background
    
    

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48. correctness
    quality
    buying time for the future
    finding regressions
    save repeated labor
    gives you confidence
    easy refactoring
    perfect bug report
    live documentation
    drive your implementation
    automation is win
    
    
    ✨
    
    
    

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49. The
    Rabbit Hole
    

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50. What is RSpec
    "
    

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52. https://relishapp.com/rspec
    RSpec Core | RSpec Expectations | RSpec Mocks | RSpec Rails
    

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53. RSpec
    Minitest
    vs
    
    

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54. A professional developer should
    be able to work in either one of
    these because they essentially do
    the same thing: test your code.
    — Dr.Tenderlove
    “
    http://tenderlovemaking.com/2015/01/23/my-experience-with-minitest-and-rspec.html
    

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55. class Something < Minitest::Test
    def test_works
    assert_equal 11, 10
    end
    def test_really_works
    assert_equal 11, 11
    end
    end
    (Unit)Test
    

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56. Test cases are
    Class Minitest::Test
    Tests are
    methods inside test case
    

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57. describe "something" do
    it "works" do
    expect(11).to equal(10)
    end
    it "really works" do
    expect(11).to equal(11)
    end
    end
    Spec(ification)
    

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58. Test cases are describe
    with description string / actual object
    and a block of tests
    Tests are it
    with description string and
    the body of test (block)
    

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60. RSpec
    RAILS
    

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61. A Gentle Introduction
    to RSpec
    
    

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62. rspec
    rspec-core
    rspec-expectations
    rspec-mocks
    MetaRubyGem
    
    
    
    

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63. How to run
    

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64. . means Passed
    F means Failure
    E means Error
    * means Pending
    S means Skip
    

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65. Sample Output
    

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67. $ rspec --init
    

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68. .rspec
    --color
    --require spec_helper
    https://relishapp.com/rspec/rspec-core/v/3-3/docs/command-line/
    

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69. spec/
    spec_helper.rb
    

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70. Magic Spells
    
    

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71. Computer science is a terrible name for this
    business. First of all, it's not a science. It
    might be engineering or it might be art, but
    we'll actually see that computer so-called
    science actually has a lot in common with
    magic.— Hal Abelson
    “
    https://youtu.be/2Op3QLzMgSY?t=27s
    

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72. describe
    it
    expect
    to
    

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73. describe
    it
    expect
    to
    a series of tests
    

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74. describe
    it
    expect
    to
    a series of tests
    is a test
    

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75. describe
    it
    expect
    to
    a series of tests
    is a test
    an actual object
    

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76. describe
    it
    expect
    to
    a series of tests
    is a test
    an actual object
    match something
    

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77. describe
    how methods works,
    group of test examples,
    series of behaviour
    

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78. describe User do
    ...
    end
    

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79. RSpec.describe
    describe
    config.disable_monkey_patching!
    in spec_helper.rb
    34QFD
    
    

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80. RSpec.describe User do
    describe ".authenticate" do
    ...
    end
    describe "#name" do
    ...
    end
    end describe can be nested
    

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81. RSpec.describe User do
    describe ".authenticate" do
    ...
    end
    describe "#name" do
    ...
    end
    end
    

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82. RSpec.describe User do
    describe ".authenticate" do
    ...
    end
    describe "#name" do
    ...
    end
    end
    

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83. RSpec.describe User do
    describe ".authenticate" do
    ...
    end
    describe "#name" do
    ...
    end
    end
    

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84. RSpec.describe User do
    describe ".authenticate" do
    ...
    end
    describe "#name" do
    ...
    end
    end
    

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85. RSpec.describe User do
    describe ".authenticate" do
    ...
    end
    describe "#name" do
    ...
    end
    end
    

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86. context
    scenarios in your
    implementation
    same as describe
    

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87. context "when…" do
    ...
    end
    context "with…" do
    end
    

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88. it
    a single test example
    inside of
    describe / context block
    

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89. it "eats something" do
    ...
    end
    

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90. describe SteveJobs do
    context "with stylus" do
    it "yucks" do
    end
    end
    end
    

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91. $ bin/rspec spec/models/steve_jobs_spec.rb --format doc
    SteveJobs
    with stylus
    yucks
    

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92. it "hello" do
    …
    end
    4JOHMF-JOF
    .VMUJ-JOF
    it { … }
    

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93. example "" do
    ...
    end
    "WPJE
    specify "" do
    ...
    end
    

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94. before
    things to do before
    test run
    

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95. before { ... }
    it "" do
    ...
    end
    

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96. before do
    ...
    end
    it "" do
    ...
    end
    

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97. after
    things to do after
    test run
    

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98. it "" do
    ...
    end
    after { ... }
    

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99. it "" do
    ...
    end
    after do
    …
    end
    

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100. inside of it
     

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101. Expectations &
     matchers come in
     

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102. expect(actual)
     expect something
     

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103. to eq(expected)
     to equal what we
     expected
     

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104. it "…" do
     expect(1+1).to eq(2)
     end
     from rspec-expectations
     

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105. it "…" do
     expect(1+1).to eq(2)
     end
     matcher
     

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106. expect(1+1).to eq(2)
     

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107. 1+1 is 2?
     Let’s prove
     

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108. 162 pages
     to prove
     1+1=2
     

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109. it "…" do
     expect(1+1).to eq(2)
     end
     Example instance
     http://git.io/vZfvX
     

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110. it "…" do
     self.expect(1+1).to self.eq(2)
     end
     Example Example
     

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111. it "…" do
     self.expect(1+1).to self.eq(2)
     end
     instance of
     ExpectationTarget
     http://git.io/vZffB
     

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112. ET = ExpectationTarget
     class Example
     def self.expect(actual)
     ET.new(actual)
     end
     end
     

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113. ET = ExpectationTarget
     class Example
     def self.expect(actual)
     ET.new(actual)
     end
     end
     

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114. ET = ExpectationTarget
     class Example
     def self.expect(actual)
     ET.new(actual)
     end
     end
     

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115. class ET
     attr_reader :actual
     def initialize(actual)
     @actual = actual
     end
     end
     

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116. it "…" do
     self.expect(1+1).to self.eq(2)
     end
     Example
     

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117. it "…" do
     self.expect(1+1).to self.eq(2)
     end
     Matcher
     

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118. class Example
     def self.eq(expected)
     EqMatcher.new(expected)
     end
     end
     EqMatcher is actually BuiltIn::Eq
     http://git.io/vZffi
     

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119. class EqMatcher
     def initialize(expected)
     @expected = expected
     end
     def matches
     ...
     end
     end
     

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120. it "…" do
     self.expect(1+1).to self.eq(2)
     end
     instance of
     ExpectationTarget
     

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121. it "…" do
     self.expect(1+1).to self.eq(2)
     end
     ExpectationTarget#to
     

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122. class ExpectationTarget
     def to(matcher)
     Postive.handle_matcher(actual, matcher)
     end
     end
     

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123. class ExpectationTarget
     def to(matcher)
     Postive.handle_matcher(actual, matcher)
     end
     end
     Postive is actually PositiveExpectationHandler
     http://git.io/vZfJK
     

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124. class Positive
     def self.handle_matcher(actual, matcher)
     matcher.matches(actual)
     end
     end
     http://git.io/vZqoX
     

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125. class Positive
     def self.handle_matcher(actual, matcher)
     matcher.matches(actual)
     end
     end
     

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126. class EqMatcher
     def matches(actual)
     match(expected, actual)
     end
     private
     def match(expected, actual)
     actual == expected
     end
     end
     

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127. class EqMatcher
     def matches(actual)
     match(expected, actual)
     end
     private
     def match(expected, actual)
     actual == expected
     end
     end
     

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128. class EqMatcher
     def matches(actual)
     match(expected, actual)
     end
     private
     def match(expected, actual)
     actual == expected
     end
     end
     http://git.io/vZfUp
     

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129. voilà, old sport!
     

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130. it "…" do
     expect(user.admin?).to be_true
     end
     `be` matcher
     be_true
     be_false
     be_truthy
     be_falsy
     be_nil
     be
     

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131. eq
     eql
     equal
     be
     be_*
     match
     be_within
     start_with
     end_with
     be_instance_of
     be_kind_of
     respond_to
     raise_error
     throw_symbol
     include
     match_array
     contain_exactly
     cover
     change
     satisfy
     output
     yield_*
     https://www.relishapp.com/rspec/rspec-expectations/docs/built-in-matchers
     
     "1*
     

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132. expect { code }.to raise_error(error, message)
     expect { post :create }
     .to raise_error(
     ActiveRecord::RecordInvalid,
     "Validation failed: name can't be blank"
     )
     raise_error matcher
     

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133. expect { code }.to change { something }.by(value)
     def do_request
     post :create, user: params
     end
     expect { do_request }.to change { User.count }.by(1)
     change matcher
     

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134. RSpec predicate
     expect(user.admin?).to be_true
     expect(user).to be_admin
     

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135. Read in English
     Most of the time
     There is a
     matcher for it
     (
     VJEF
     

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136. Stick with eq
     as a Starting Point
     (
     VJEF
     KISS
     
     

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137. expect(user.admin?).to be_true
     expect(user.admin?).to eq true
     

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138. RSpec built-in
     matchers have
     better error messages
     (
     VJEF
     

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139. let
     lazily-evaluated block
     to shared object between tests
     

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140. describe Baz
     let(:foo) { "bar" }
     it "…" do
     ...
     end
     end
     foo will be available in it
     blocks under the same scope!
     

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141. let(:foo) { sleep 42 }
     it "…" do
     ...
     end
     Finished in 0.04424 seconds
     it "…" do
     ...
     end
     

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142. let(:foo) { sleep 42 }
     it "…" do
     foo
     end
     Finished in 42.03924 seconds
     it "…" do
     ...
     end
     

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143. let!(:foo) { sleep 42 }
     it "…" do
     ...
     end
     Finished in 42.03924 seconds
     it "…" do
     ...
     end
     

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144. Prefer let over
     @instance_var
     (
     VJEF
     

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145. RSpec Mocks
     

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146. RSpec Mocks
     To mock a mocking bird
     

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147. We are dealing with
     objects and objects
     

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148. collaborators of
     each other
     

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149. Sometimes
     it costs a lot to setup
     collaborators
     

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150. TDD
     Tired-Driven Development
     

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151. Move Fast and
     Break Things
     drive slow but stay safe
     

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152. Double
     

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154. A fake object for
     real object
     

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155. RSpec::Mocks::
     ExampleMethods
     #double
     http://git.io/vZq6F
     "1*
     

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156. user = double("User")
     

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157. Faking message and
     its return value
     

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158. RSpec::Mocks::
     ExampleMethods
     #allow
     http://git.io/vZq6F
     "1*
     

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159. allow(obj).to receive(:msg).and_return(value)
     

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160. user = double("User")
     allow(user).to
     receive(:admin?).
     and_return(true)
     allow(user).to receive(:admin?) { true }
     

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161. user = double("User")
     allow(user).to
     receive(:admin?).
     and_return(true)
     allow(user).to receive(:admin?) { true }
     

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162. user = double("User")
     allow(user).to
     receive(:admin?).
     and_return(true)
     allow(user).to receive(:admin?) { true }
     

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163. user.admin?
     => true
     

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164. user =
     double("User", admin?: true)
     

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165. Stub & Mock
     

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166. context "stub and mock" do
     describe "stub" do
     it "won't verify" do
     allow(User).to receive(:new)
     # User.new
     end
     end
     describe "mock" do
     it "will verify" do
     expect(User).to receive(:new)
     # User.new
     end
     end
     end
     

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167. context "stub and mock" do
     describe "stub" do
     it "won't verify" do
     allow(User).to receive(:new)
     # User.new
     end
     end
     describe "mock" do
     it "will verify" do
     expect(User).to receive(:new)
     # User.new
     end
     end
     end
     Stub
     

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168. context "stub and mock" do
     describe "stub" do
     it "won't verify" do
     allow(User).to receive(:new)
     # User.new
     end
     end
     describe "mock" do
     it "will verify" do
     expect(User).to receive(:new)
     # User.new
     end
     end
     end
     Mock
     

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169. context "stub and mock" do
     describe "stub" do
     it "won't verify" do
     allow(User).to receive(:new)
     # User.new
     end
     end
     describe "mock" do
     it "will verify" do
     expect(User).to receive(:new)
     # User.new
     end
     end
     end
     Failure/Error: expect(User).to receive(:new)
     
     Mock
     

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170. Mock will verify
     While Stub not
     

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171. context "stub and mock" do
     describe "stub" do
     it "stub and verify" do
     allow(User).to receive(:new)
     User.new
     expect(User).to have_received(:new)
     end
     end
     end
     

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172. context "stub and mock" do
     describe "stub" do
     it "won't verify" do
     allow(User).to receive(:new)
     User.new
     expect(User).to have_received(:new)
     end
     end
     end
     Strategy Spaces
     

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173. Phases of Testing
     

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174. setup
     exercise
     verify
     teardown
     everything we need
     the real work
     our expectations
     back to original state
     

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175. Encrypt user password
     in database
     &YBN
     QMF
     

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176. setup
     user =
     User.new(password: "passw0rd")
     

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177. user.save
     exercise
     

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178. expect(user.encrypted_password).to be_present
     verify
     

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179. RSpec’ve got us covered
     teardown
     

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180. before { user = User.new(password: "passw0rd") }
     it "should encrypt password" do
     user.save
     expect(user.encrypted_password).not_to eq nil
     end
     Put together
     

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181. it "should encrypt password" do
     user = User.new(password: "passw0rd")
     user.save
     expect(user.encrypted_password).not_to eq nil
     end
     Strategy Spaces
     

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182. Spy
     

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183. Like 007,
     can do
     anything
     

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184. Can
     respond
     to any
     messages
     

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185. oo7 = spy
     oo7.can_jump?
     oo7.can_drive_car?
     oo7.can_play_poker?
     oo7.can_write_ruby?
     

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186. spy is the Null
     Object of double
     spy = double.as_null_object
     

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187. oo7 = spy
     oo7.hungry?
     expect(oo7).to have_received(:hungry?)
     

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188. oo7 = spy
     oo7.tired?
     expect(oo7).to have_received(:tired?)
     Just like Stub!
     

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189. RSpec 2 v.s RSpec 3
     make stub and mock
     is confusing
     

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190. But you can
     just try and
     explore their
     difference
     

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191. That’s enough to
     write many tests!
     

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192. RSpec & Rails
     

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193. gem "rspec-rails"
     bundle
     rails generate rspec:install
     *OTUBMM
     in development and test group
     

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194. spec/
     rails_helper.rb
     Only when you need Rails
     

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195. Try not to load
     rails_helper
     whenever possible
     5JQ
     

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196. config.infer_spec_type_from_file_location!
     # spec/models/user_spec.rb
     RSpec.describe User, type: :model do
     # automatically mixin functionalities
     end
     Infer type of test automatically
     

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197. Metadata
     

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198. RSpec.describe User, type: :model do
     end
     metadata
     

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199. According to type of tests,
     RSpec will mixin
     different functionality
     automagically
     

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200. RSpec.describe User, focus: true do
     end
     metadata
     $ rspec --tag focus
     only run spec with special tag
     

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201. Rails & Testing
     

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202. RAILS_ENV = test
     config/environments/test.rb
     

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203. bin/rake db:test:prepare
     run pending migrations and load schema
     https://github.com/rails/rails/blob/v4.2.4/activerecord/lib/active_record/railties/databases.rake#L359-L364
     

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204. ActiveSupport::TestCase
     ActionController::TestCase
     ActionMailer::TestCase
     ActionView::TestCase
     ActiveJob::TestCase
     ActionDispatch::IntegrationTest
     Read these API docs on
     http://api.rubyonrails.org/
     

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205. Fixture
     

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206. Fixture
     # spec/fixtures/users.yml
     juanitofatas:
     name: JuanitoFatas
     email: juanito@jollygoodcode.com
     # spec/rails_helper.rb
     RSpec.configure do |config|
     config.fixture_path = "#{::Rails.root}/spec/fixtures"
     config.use_transactional_fixtures = true
     end
     # under describe or context
     users :juanitofatas
     # => #
     

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207. FactoryGirl
     A DSL to generate objects
     

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208. # spec/factories/user.rb
     Factory.define do
     factory :user do
     name "Juanito Fatas"
     email "juanito@jollygoodcode.com"
     end
     end
     

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209. FactoryGirl.attributes_for(:user)
     # => {
     name: "JuanitoFatas",
     email: "juanito@jollygoodcode.com"
     }
     

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210. # In spec
     FactoryGirl.create(:user)
     FactoryGirl.build(:user)
     # Map to Active Record
     User.create(…)
     User.new(…)
     

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211. gem "factory_girl_rails"
     bundle
     mkdir spec/factories
     *OTUBMM
     in development and test group
     

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212. spec/factories/*.rb
     $POWFOUJPO
     * is respective model name, user.rb
     

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213. RSpec.configure do |config|
     config.include FactoryGirl::Syntax::Methods
     end
     $PO
     H
     create(:user) instead of
     FactoryGirl.create(:user)
     https://github.com/thoughtbot/factory_girl/blob/master/GETTING_STARTED.md
     

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214. Minimum
     Valid
     Object
     5JQ
     

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215. Types of Test
     

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216. https://robots.thoughtbot.com/rails-test-types-and-the-testing-pyramid
     

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217. https://robots.thoughtbot.com/rails-test-types-and-the-testing-pyramid
     Bottom
     Top
     

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218. https://robots.thoughtbot.com/rails-test-types-and-the-testing-pyramid
     Inside Outside
     

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219. https://robots.thoughtbot.com/rails-test-types-and-the-testing-pyramid
     User
     Code
     

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220. https://robots.thoughtbot.com/rails-test-types-and-the-testing-pyramid
     Coverage
     

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221. https://robots.thoughtbot.com/rails-test-types-and-the-testing-pyramid
     Fast Slow
     

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222. View Slide

223. Feature Spec
     Outside-in, Acceptance / Customer Test, End-to-End, Top down
     

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224. require "rails_helper"
     spec/features/*_spec.rb
     $POWFOUJPO
     

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225. (
     PBM
     Automate the manual
     repeated process
     Browser, check, refresh, repeat
     

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226. Test like how user use it
     Use real database records
     Don’t mock or stub objects
     External Service can stub
     5JQ
     

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227. Happy Path for
     a given feature
     5JQ
     

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228. API to interact
     with Browser
     (
     FN
     T
     capybara
     Version 2.4.0+ is recommended
     

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229. group :development, :test do
     gem "capybara"
     end
     bundle install
     *OTUBMM
     

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230. require "capybara/rails"
     # in spec/rails_helper.rb
     $PO
     H
     

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231. database_rewinder
     (
     FN
     T
     Ensure clean
     state across tests
     

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232. group :test do
     gem "database_rewinder"
     end
     *OTUBMM
     

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233. RSpec.configure do |config|
     config.before :suite do
     DatabaseRewinder.clean_all
     end
     config.after :each do
     DatabaseRewinder.clean
     end
     end
     $PO
     H
     

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234. background
     feature
     scenario
     given
     "1*
     

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235. &YBN
     QMF
     feature "Auth" do
     given { ... }
     background { ... }
     scenario "show name" do
     ...
     end
     end
     

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236. background
     feature
     scenario
     given
     before
     describe
     it
     let
     http://git.io/vGyaV
     alias
     alias
     alias
     alias
     "1*
     

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237. RSpec.feature "…" do
     end
     Capybara API will be
     available in here
     http://www.rubydoc.info/github/jnicklas/capybara/master#The_DSL
     

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238. "1*
     page
     visit
     current_path
     click_on
     find
     fill_in
     choose
     check
     select
     attach_file
     https://github.com/jnicklas/capybara#the-dsl
     

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239. 3BDL5FTU
     Fastest
     No JavaScript
     Can access within Rack
     No Server Required
     

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240. &YBN
     QMF
     feature "Sign In" do
     scenario "works" do
     visit root_path
     click_on "Sign In"
     fill_in "login", with: "JuanitoFatas"
     fill_in "password", with: "1passw0rd"
     click_on "Sign In"
     end
     end
     

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241. &YBN
     QMF
     feature "Auth" do
     scenario "show name" do
     create(:user, name: "Juan")
     sign_in_as(user)
     expect(page).to have_content("Juan")
     end
     end
     

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242. &YBN
     QMF
     feature "Vote" do
     scenario "upvote" do
     create(:user, name: "Juan")
     sign_in_as(user)
     expect(page).to have_content("Votes 0")
     find("upvote").click
     expect(page).to have_content("Votes 1")
     end
     end
     

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243. Drivers
     

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244. %
     SJWFST
     Plain
     Firefox
     Webkit
     PhantomJS
     Rack-Test
     Selenium
     Capybara-webkit
     Poltergeist
     Single DSL to rule them all
     

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245. RSpec.describe User, js: true do
     ...
     end
     enable javascript_driver
     #SPX
     TFS
     

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246. 4FMFOJVN
     Selenium 2.0
     Firefox
     JavaScript
     Can access Remote API
     EFGBVMU
     

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247. $BQZCBSB8FCLJU
     Headless Testing
     JavaScript
     Faster than selenium
     

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248. 1PMUFSHFJTU
     Headless Testing
     JavaScript
     Can Find JS Error
     No render engine needed
     

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249. Capybara.default_driver
     Capybara.javascript_driver
     $PO
     H
     

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250. Controller Spec
     Functional Test
     

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251. require "rails_helper"
     spec/controllers/*_spec.rb
     describe "#action"
     $POWFOUJPO
     * is respective controller name
     

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252. require "rails_helper"
     RSpec.describe ShopsController do
     describe "#index" do
     ...
     end
     describe "#new" do
     ...
     end
     describe "#create" do
     ...
     end
     …
     $POWFOUJPO
     

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253. describe "#show" do
     ...
     end
     describe "#edit" do
     ...
     end
     describe "#update" do
     ...
     end
     describe "#destroy" do
     ...
     end
     end
     $POWFOUJPO
     

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254. 5JQ
     Ordering should be the same
     as your actions in controller
     index new create show edit update destroy
     

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255. response correct & success
     redirected right
     authentications
     session, flash, cookie
     render correct template
     instance variable
     (
     PBM
     

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256. params
     request
     response
     session
     flash
     cookie
     "1*
     get
     post
     patch
     put
     head
     delete
     ActionController::TestCase
     

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257. expect(response).to render_template(:index)
     expect(response).to redirect_to(location)
     expect(response.status).to eq(200)
     expect(flash[:alert]).to eq I18n.t("failed")
     "1*
     

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258. Can wrap request in
     method — abstractions
     5JQ
     def do_request
     get :show, params
     end
     

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259. RSpec.describe HomeController do
     describe "#index" do
     def do_request
     get :index
     end
     it "works" do
     do_request
     expect(response).to be_success
     end
     end
     end
     JOEFY
     

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260. describe HomeController do
     describe "#index" do
     def do_request
     get :index
     end
     it "works" do
     do_request
     expect(response).to be_success
     end
     end
     end
     &YBN
     QMF
     same scope
     

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261. RESTful
     controller spec
     

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262. RSpec.describe ThingsController do
     end
     TLFMUPO
     

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263. describe "#index" do
     def do_request
     get :index
     end
     before { do_request }
     it { expect(response).to be_success }
     end
     JOEFY
     

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264. describe "#new" do
     def do_request
     get :new
     end
     before { do_request }
     it { expect(response).to be_success }
     end
     OFX
     

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265. describe "#create" do
     def do_request
     post :create, thing: params
     end
     context "success" do
     ...
     end
     context "failure" do
     ...
     end
     end
     DSFBUF
     

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266. describe "#show" do
     let(:thing) { create(:thing) }
     def do_request
     get :show, id: thing
     end
     before { do_request }
     it { expect(response).to be_success }
     end
     TIPX
     

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267. FEJU
     describe "#edit" do
     let(:thing) { create(:thing) }
     def do_request
     get :edit, id: thing.id
     end
     before { do_request }
     it { expect(response).to be_success }
     end
     

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268. describe "#update" do
     let(:thing) { create(:thing) }
     def do_request
     patch :update, id: thing.id, thing: params
     end
     before { do_request }
     context "success" do
     ...
     end
     context "failure" do
     ...
     end
     end
     VQEBUF
     

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269. describe "#destroy" do
     let!(:thing) { create(:thing) }
     def do_request
     delete :destroy, id: thing.id
     end
     it "redirects" do
     expect { do_request }.to change(Thing, :count).by(-1)
     expect(response).to redirect_to things_path
     end
     end
     EFTUSPZ
     

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270. 5JQ
     Try to keep the specs shape
     the same across controllers
     

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271. 3BJMT
     post :show,
     { id: 1 },
     { user_id: 1 },
     { notice: "flash message" }
     

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272. 3BJMT
     post :show,
     { id: 1 },
     {},
     { notice: "flash message" }
     params
     session
     flash
     

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273. 3BJMT
     post :show,
     { shop_id: 1 },
     {},
     { notice: "flash message" }
     params
     session
     flash
     

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274. 3BJMT
     post :show,
     params: { shop_id: 1 },
     session: { user_id: 1 },
     flash: { notice: "flash message" }
     Rails 5 Switch to Keyword Arguments
     https://github.com/rails/rails/pull/18323
     

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275. 5JQ
     Wrap things in Objects,
     only test message has been
     invoked in controller
     skinny controller
     

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276. describe "#create" do
     context "success" do
     it "sent welcome mail" do
     allow(UserMailer).to receive(:welcome)
     do_request
     expect(UserMailer).to have_received(:welcome)
     end
     end
     end
     &YBN
     QMF
     

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277. describe "#create" do
     context "success" do
     it "sent welcome mail" do
     allow(Payment).to receive(:charge!)
     do_request
     expect(Payment).to have_received(:charge!)
     end
     end
     end
     

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278. Model Spec
     

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279. Test how you tried
     in rails console
     (
     PBM
     

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280. require "rails_helper"
     spec/models/*_spec.rb
     $POWFOUJPO
     

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281. describe User do
     context "associations" do; end
     context "validations" do; end
     describe ".class_method" do; end
     describe "#instance_method" do; end
     end
     $POWFOUJPO
     

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282. Use shoulda
     to write one-liner spec
     for associations and
     validations
     5JQ
     

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283. ActiveSupport::TestCase
     3BJMT
     

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284. describe User do
     context "associations" do
     it { expect(User.new).to have_many(:repos) }
     end
     end
     "TTPDJBUJPO
     

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285. describe User do
     subject { User.new }
     context "associations" do
     it { expect(subject).to have_many(:repos) }
     end
     end
     &YBN
     QMF
     Implicit subject
     

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286. describe User do
     context "associations" do
     it { is_expected.to have_many(:repos) }
     end
     end
     &YBN
     QMF
     

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287. describe User do
     context "associations" do
     it { is_expected.to validate_presence_of :name }
     end
     end
     7BMJEBUJPO
     

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288. Post.trending
     scope :trending,
     -> { order("upvotes DESC") }
     describe Post do
     describe ".trending" do
     popular = create(:post, upvotes: 42)
     just_created = create(:post, upvotes: 1)
     trending_posts = Post.trending
     expect(trending_posts).to \
     eq [popular, just_created]
     end
     end
     

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289. Helper Spec
     

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290. (
     PBM
     Test the view helper as
     you expected
     

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291. require "rails_helper"
     spec/helpers/*_spec.rb
     $POWFOUJPO
     

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292. require "rails_helper"
     describe EventsHelper do
     describe "#linkify_event" do
     it "works" do
     expect(linkify_event).to eq "RubyKaigi 11st-13rd Dec, 2015"
     end
     end
     end
     &YBN
     QMF
     

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293. require "rails_helper"
     describe EventsHelper do
     describe "#linkify_event" do
     it "works" do
     expect(linkify_event).to eq "RubyKaigi 11st-13rd Dec, 2015"
     end
     end
     end
     EventsHelper::LinkifyEvent
     

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294. require "rails_helper"
     describe EventsHelper do
     describe "#linkify_event" do
     it "works" do
     self
     expect(linkify_event).to eq "RubyKaigi 11st-13rd Dec, 2015"
     end
     end
     end
     RSpec::ExampleGroups::
     EventsHelper::LinkifyEvent
     

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295. require "rails_helper"
     describe EventsHelper do
     describe "#linkify_event" do
     it "works" do
     expect(linkify_event).to eq "RubyKaigi 11st-13rd Dec, 2015"
     end
     end
     end
     

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296. Mailer Spec
     

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297. ActionMailer::TestCase
     ActionMailer::Base.deliveries
     ActionMailer::MessageDelivery
     3BJMT
     

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298. spec/mailers/*_spec.rb
     $POWFOUJPO
     

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299. email_spec
     (
     FN
     T
     Why this not in
     RSpec?
     

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300. group :test do
     gem "email_spec"
     end
     *OTUBMM
     

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301. # Either in spec/rails_helper.rb or
     # spec/email_helper.rb
     require "email_spec"
     RSpec.configure do |config|
     config.include EmailSpec::Helpers
     config.include EmailSpec::Matchers
     end
     $PO
     H
     

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302. reply_to
     deliver_to
     deliver_from
     bcc_to
     cc_to
     "1*
     have_subject
     have_body_text
     have_header
     

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303. Sent successfully
     Sent at correct time
     Sent to right person
     Email content
     (
     PBM
     

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304. class UserMailer < ActionMailer::Base
     def welcome_user(user)
     @user = user
     mail(
     to: @user.email,
     subject: "Welcome to JollyGoodCode!"
     )
     end
     end
     &YBN
     QMF
     

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305. RSpec.describe UserMailer do
     describe "#welcome_user" do
     let(:user) { build_stubbed(:user) }
     let(:email) { email_for(user) }
     def email_for(user)
     UserMailer.welcome_user(user)
     end
     it { expect(email).to have_subject "Welcome to JollyGoodCode!" }
     it { expect(email).to deliver_to user.email }
     end
     end
     &YBN
     QMF
     

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306. Job Spec
     

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307. Job invokes correct
     methods
     (
     PBM
     

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308. ActiveJob::TestCase
     ActiveJob::TestHelper
     3BJMT
     

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309. spec/jobs/*_spec.rb
     $POWFOUJPO
     

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310. it "sync repos" do
     allow(RepoSync).to receive(:new)
     RepoSyncJob.perform_now(repo)
     expect(RepoSync).to have_received(:new)
     end
     &YBN
     QMF
     Sending right messages
     

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311. it "sync repos" do
     allow(RepoSync).to receive(:new)
     RepoSyncJob.perform_now(repo)
     expect(RepoSync).to have_received(:new)
     end
     &YBN
     QMF
     Logic should be already tested
     in RepoSync specs
     

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312. View Spec
     

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313. Request Spec
     

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314. Plain Old
     Ruby Object
     

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315. Similar to
     Model Spec
     without
     loading Rails
     

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316. Interact with
     the world
     

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317. Run without network
     Avoid connectivity
     issues
     (
     PBM
     

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318. API limit
     Slower
     Test relies on internet
     Service no sandbox
     mode
     Service not exist
     8
     IZ
     

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319. spec/**/*_spec.rb
     '3
     &&%
     0
     .
     lib/github_client.rb
     spec/lib/github_client_spec.rb
     

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320. webmock
     (
     FN
     T
     Making real
     request
     IS A CRIME
     

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321. group :test do
     gem "webmock"
     end
     *OTUBMM
     

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322. require "webmock/rspec"
     WebMock.disable_net_connect!
     (allow_localhost: true)
     $PO
     H
     

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323. stub_request(
     HTTP verb, path
     ).with(
     HEADER HASH
     ).to_return(
     RESPONSE HASH
     )
     4UVCCJOH
     

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324. expect(WebMock).to
     have_requested(…).
     with(…)
     4FUUJOH&YQFDUBUJPOT
     

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325. expect(
     a_request(…)
     ).to have_been_made
     4FUUJOH&YQFDUBUJPOT
     

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326. VCR
     (
     FN
     T
     Record response from real
     API or service
     cassettes
     

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327. $ curl
     File.read
     Ruby Objects
     Faking responses
     

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328. it "webmock example" do
     url = "https://api.github.com/users/juanitofatas"
     fixture = "spec/fixtures/github/juanitofatas.json"
     # stub_request(:get, url).
     to_return(body: File.read(fixture))
     HTTP.get(url)
     expect(WebMock).to have_requested(:get, url)
     expect(a_request(:get, url)).to have_been_made
     end
     &YBN
     QMF
     

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329. &YBN
     QMF
     

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330. it "webmock example" do
     url = "https://api.github.com/users/juanitofatas"
     fixture = "spec/fixtures/github/juanitofatas.json"
     stub_request(:get, url).
     to_return(body: File.read(fixture))
     HTTP.get(url)
     expect(WebMock).to have_requested(:get, url)
     expect(a_request(:get, url)).to have_been_made
     end
     &YBN
     QMF
     

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331. it "webmock example" do
     url = "https://api.github.com/users/juanitofatas"
     fixture = "spec/fixtures/github/juanitofatas.json"
     stub_request(:get, url).
     to_return(body: File.read(fixture))
     HTTP.get(url)
     expect(WebMock).to have_requested(:get, url)
     expect(a_request(:get, url)).to have_been_made
     end
     &YBN
     QMF
     

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332. it "webmock example" do
     url = "https://api.github.com/users/juanitofatas"
     fixture = "spec/fixtures/github/juanitofatas.json"
     stub_request(:get, url).
     to_return(body: File.read(fixture))
     HTTP.get(url)
     expect(WebMock).to have_requested(:get, url)
     expect(a_request(:get, url)).to have_been_made
     end
     &YBN
     QMF
     

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333. it "webmock example" do
     url = "https://api.github.com/users/juanitofatas"
     fixture = "spec/fixtures/github/juanitofatas.json"
     stub_request(:get, url).
     to_return(body: File.read(fixture))
     HTTP.get(url)
     expect(WebMock).to have_requested(:get, url)
     expect(a_request(:get, url)).to have_been_made
     end
     &YBN
     QMF
     

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334. it "webmock example" do
     url = "https://api.github.com/users/juanitofatas"
     fixture = "spec/fixtures/github/juanitofatas.json"
     stub_request(:get, url).
     to_return(body: File.read(fixture))
     HTTP.get(url)
     expect(WebMock).to have_requested(:get, url)
     expect(a_request(:get, url)).to have_been_made
     end
     &YBN
     QMF
     https://github.com/sferik/t
     

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335. &YBN
     QMF
     many stub_request examples
     sferik/t
     

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336. Debugging
     

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337. stop spring
     pry-rails + binding.pry
     byebug everywhere
     p + puts + pp + raise
     

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338. Closing
     

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339. Routing, Request, View Specs
     Page Object (Feature Spec)
     Front-end Testing
     Infrastructure Testing
     A/B Testing
     Smoke Testing (example)
     

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340. Routing Specs
     Request Specs
     View Specs
     Page Object (Feature Spec)
     Front-end Testing
     Infrastructure Testing
     A/B Testing
     Smoke Testing (example)
     NOT
     COVERED
     

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341. LEGACY CODE
     

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342. Skip
     Pending
     v.s.
     not run at all
     run but won’t failed
     

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343. 1. Write Feature Spec
     2. New things with
     specs
     3. Use Exception
     monitoring service
     

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344. 1. Write Feature Spec
     2. New things with
     specs
     3. Use Exception
     monitoring service
     4. Find another job
     

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345. DON’T TEST
     private Method
     test the method which uses it
     

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346. Wrap Everything
     in objects
     so much easier to test
     

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347. Use shoulda to
     simplify when
     you get tired.
     

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348. Use tools to
     simplify when
     you get tired.
     

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349. Don’t aim for
     100% test
     coverage
     

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350. I get paid for code that
     works, so my philosophy is
     to test as little as possible to
     reach a given level of
     confidence.— Kent Back
     “
     

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351. We read more
     than we write
     

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352. Anything that
     can go wrong,
     will go wrong
     

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353. That’s why
     we write tests
     

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354. Tests are also
     code. Will
     become stinky,
     break up when
     it’s time
     

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355. There are
     million ways
     of how things
     are tested
     

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356. There’s no
     tomorrow.
     

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357. WRITE
     TEST
     NOW
     

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358. A test is
     better
     than no test
     

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359. Feature
     Model
     Controller
     

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360. Do
     Code
     Review
     

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361. Team
     Style
     Guide
     

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362. Takeaways
     

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363. ALWAYS
     BE
     TESTING
     

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364. Resource
     

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365. Talks
     

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366. https://www.youtube.com/watch?v=MA4jJNUG_dI
     

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367. http://git.io/vsOKE
     

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368. https://www.youtube.com/watch?v=Libc0-0TRg4
     

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369. Books
     

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370. View Slide

371. https://leanpub.com/rspecbook
     RUBYCONFTW2015
     ⯜顤
     8
     PSL*O1SPHSFTT
     IPROMISEYOUIWILLWRITETESTS !
     ✿䫓 !
     45RGE⑆桡⻇㔑
     D[,WCPKVQ(CVCU
     

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372. Talk to me!
     I’m happy to help you
     

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373. 6JCPM[QW
     HQT.KUVGPKPI
     

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374. 6GC6KOG
     ☕
     

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375. View Slide