An RSpec 3 Talk

A talk about RSpec 3 that I gave at LRUG December 2014.

Transcript

1. An RSpec 3 Talk
2. a!/samphippen
3. RSpec RSpec ! ! RSpec 3
4. Upgrading
5. The easiest major gem upgrade you’ve ever done
6. The upgrade process
7. Be green and warning free on RSpec 2
8. gem “rspec”, “~> 2.99”
9. bundle install
10. fix warnings
11. gem “rspec”, “~> 3.0”
12. Done.
13. There is also Transpec
15. Verifying doubles
16. Who’s ever stubbed an object’s interface wrong?
17. class Foo def bar(beers) “#{beers} bottles of beer” end end
18. allow(Foo.new).to receive(:bare)
20. class Foo def bar(beers) “#{beers} bottles of beer” end end
21. allow(Foo.new).to receive(:bar).with(1,2)
23. Not enabled by default for upgrade installs
24. RSpec.configure do |config| config.mock_with :rspec do |mocks| mocks.verify_partial_doubles = true end end
25. http://tinyurl.com/p6yk8ll
26. Verifying behaviour on pure doubles
27. double( :some_name_for_the_double, :call => :result )
28. instance_double( MyClass, :call => :result )
29. instance_double( MyClass, :call => :result )
30. instance_double( “MyClass”, :call => :result )
31. Let’s have some questions !!/samphippen sam@funandplausible.com
32. Also class_double and object_double
33. Composable matchers
34. One Expectation Per Test
35. expect(json[“foo”]).to eq(bar) expect(json[“baz”]).to eq(quz) expect(json[“boz”][“buz”]).to match(id_regex)
36. expect(json[“foo”]).to eq(bar) expect(json[“baz”]).to eq(quz) expect(json[“boz”][“buz”]).to match(id_regex)
37. Could write separate tests
38. That could be expensive
39. expect(json).to match( “foo” => bar, “baz” => quz, “boz” => { “buz” => match(id_regex) } )
40. Match parts of hashes and arrays
41. { “key” => { “key1” => value1, “key2” => value2, } }
42. expect(foo).to match( “key” => a_hash_including( “key2”=> value2 ) )
43. { “key” => [1,2,3] }
44. expect(foo).to match( “key” => an_array_including(1) )
45. Compound expressions via and and or
46. expect(alphabet).to start_with("a") expect(alphabet).to end_with("z")
47. expect(alphabet) .to start_with(“a”) .and end_with("z")
48. expect(stoplight.color) .to eq(“red") .or eq(“green") .or eq("yellow")
49. Nearly all existing RSpec matchers are composable
50. Works with custom matchers
51. Rails
52. Let’s have some questions !!/samphippen sam@funandplausible.com
53. OMG. Loading rails is the worst thing ever
54. files took 2.09 seconds to load
55. spec_helper is now split
56. spec_helper.rb Loads RSpec, not your app
57. rails_helper.rb Loads RSpec + whole rails app
58. Spec Types
59. RSpec rails used to be highly implicit
60. #spec/controllers/foo_controller_spec.rb describe FooController it “magically has get and assigns methods????” get :index expect(assigns[:foo]).to be true end end
61. #spec/controllers/foo_controller_spec.rb describe FooController, :type => :controller it “gets the methods from the metadata” get :index expect(assigns[:foo]).to be true end end
62. This applies to all Rails spec types
63. You can structure your specs however you like
64. If you badly need directory based spec inference
65. RSpec.configure do |config| config.infer_spec_type_from_file_location! end
66. http://tinyurl.com/kgllgtb
67. RSpec is trying to get less bad at patching methods on to everything for you
68. Sytnax
69. The “a.should == b” syntax is not gone
70. It is deprecated
71. I strongly advise you to use expect(a).to eq(b) everywhere
72. a.should == b expect(a).to eq(b)
73. a.should_receive(:foo) expect(a).to receive(:foo)
74. a.stub(:foo) allow(a).to receive(:foo)
75. expect { }.to raise_error ! #is the same
76. a.any_instance.stub(:foo) allow_any_instance_of(a).to receive(:foo)
77. a.any_instance.should_receive(:foo) expect_any_instance_of(a).to receive(:foo)
78. RSpec also now has a “no monkey patching” mode
79. RSpec 2 monkey patches #describe
80. describe “” do describe “” do end it “” do end end
81. RSpec.describe “” do describe “” do end it “” do end end
82. bare describe is still available in RSpec contexts
83. This one might trip you up
84. be_true be_false
85. be_truthy be_falsy be_falsey
86. be true be false
87. Let’s have some questions a!/samphippen sam@funandplausible.com