Fix - Simple, stupid testing framework for Ruby

Transcript

1. Fix Simple, stupid testing framework for Ruby March 1, 2016

2. github.com/cyril Cyril Kato twitter.com/cyri_

3. Chess Gungi Shogi Xiangqi

4. Let’s begin with a survey...

5. Who likes RSpec?

6. None

7. Even for simple code?

8. Even for simple code? Let’s take an example

9. 0-example/app.rb APP = 42

10. 0-example/app_spec.rb require_relative 'app' require 'rspec' RSpec.describe APP do it {

    expect(described_class).to be 42 } end

11. 0-example/app_small_test.rb require_relative 'app' fail unless 42.equal?(APP)

12. Both tests are passing: ➜ ruby 0-example/app_small_test.rb ➜ rspec 0-example/app_spec.rb

    . Finished in 0.00098 seconds 1 example, 0 failures

13. Both tests are passing. But...

14. Testing with RSpec, the result was processed over... rspec 3.4.0

    63 LOC

15. Testing with RSpec, the result was processed over... rspec 3.4.0

    rspec-core 3.4.3 63 LOC 7 389 LOC +

16. Testing with RSpec, the result was processed over... rspec 3.4.0

    rspec-core 3.4.3 rspec-expectations 3.4.0 63 LOC 7 389 LOC 3 917 LOC + +

17. Testing with RSpec, the result was processed over... rspec 3.4.0

    rspec-core 3.4.3 rspec-expectations 3.4.0 rspec-mocks 3.4.1 63 LOC 7 389 LOC 3 917 LOC 4 106 LOC + + +

18. Testing with RSpec, the result was processed over... rspec 3.4.0

    rspec-core 3.4.3 rspec-expectations 3.4.0 rspec-mocks 3.4.1 rspec-support 3.4.1 63 LOC 7 389 LOC 3 917 LOC 4 106 LOC 1 624 LOC + + + +

19. Testing with RSpec, the result was processed over... rspec 3.4.0

    rspec-core 3.4.3 rspec-expectations 3.4.0 rspec-mocks 3.4.1 rspec-support 3.4.1 diff-lcs 1.2.5 63 LOC 7 389 LOC 3 917 LOC 4 106 LOC 1 624 LOC 1 405 LOC + + + + +

20. Testing with RSpec, the result was processed over... rspec 3.4.0

    rspec-core 3.4.3 rspec-expectations 3.4.0 rspec-mocks 3.4.1 rspec-support 3.4.1 diff-lcs 1.2.5 63 LOC 7 389 LOC 3 917 LOC 4 106 LOC 1 624 LOC 1 405 LOC + + + + + 18 504 LOC!!
21. None
22. None
23. None

24. In the other case, with Ruby’s fail(*args)

25. 1 LOC

26. Both tests are passing. Butthe second is more relevant.

27. complexity(testing tool) SHOULD be < complexity(code)

28. Code to test Testing tool

29. BTW

30. None

31. ANYWAY Here’s another example

32. require 'rspec' RSpec.describe(-42) do describe '#abs' do it { expect(described_class.abs).to

    equal 42 } end end

33. require 'rspec' RSpec.describe(-42) do describe '#abs' do it { expect(described_class.abs).to

    equal 42 } end end Same method, but different behavior

34. require 'rspec' RSpec.describe(-42) do describe '#abs' do it { expect(described_class.abs).to

    equal 42 } end end I don’t care about class or instance methods

35. require 'rspec' RSpec.describe(-42) do describe '#abs' do it { expect(described_class.abs).to

    equal 42 } end end We need to repeat the code

36. ZOMG FIX new specing framework

37. require 'fix' Fix.describe(-42) do on :abs do it { MUST

    equal 42 } end end

38. require 'fix' Fix.describe(-42) do on :abs do it { MUST

    equal 42 } end end The front object

39. require 'fix' Fix.describe(-42) do on :abs do it { MUST

    equal 42 } end end An event

40. require 'fix' Fix.describe(-42) do on :abs do it { MUST

    equal 42 } end end A subject

41. require 'fix' Fix.describe(-42) do on :abs do it { MUST

    equal 42 } end end An absolute requirement

42. RFC 2119 compliant

43. The key words "MUST", "MUST NOT", "SHOULD", "SHOULD NOT", and

    "MAY" in this document are to be interpreted as described in RFC 2119.

44. What about code isolation

45. require 'rspec' greeting = 'Hello world!' RSpec.describe greeting do context

    'Alice' do before { greeting.gsub!('world', 'Alice') } it { expect(greeting).to eql 'Hello Alice!' } end context 'Bob' do before { greeting.gsub!('world', 'Bob') } it { expect(greeting).to eql 'Hello Bob!' } end end

46. require 'rspec' greeting = 'Hello world!' RSpec.describe greeting do context

    'Alice' do before { greeting.gsub!('world', 'Alice') } it { expect(greeting).to eql 'Hello Alice!' } end context 'Bob' do before { greeting.gsub!('world', 'Bob') } it { expect(greeting).to eql 'Hello Bob!' } end end No isolation of the code to avoid the side effects

47. ➜ rspec 2-example/greeting_spec.rb .F Failures: 1) Hello world! Bob should

    eql "Hello Bob!" Failure/Error: it { expect(greeting).to eql 'Hello Bob!' } expected: "Hello Bob!" got: "Hello Alice!" Finished in 0.01521 seconds 2 examples, 1 failure

48. require 'fix' greeting = 'Hello world!' Fix.describe greeting do context

    'Alice' do on :gsub!, 'world', 'Alice' do it { MUST eql 'Hello Alice!' } end end context 'Bob' do on :gsub!, 'world', 'Bob' do it { MUST eql 'Hello Bob!' } end end end

49. ➜ ruby 2-example/greeting_fix.rb .. Ran 2 tests in 0.005775 seconds

    100% compliant - 0 infos, 0 failures, 0 errors

50. With Fix, no side effects outside contexts

51. no particular Style Guide

52. Don't make me think

53. describe "#foo" or describe ".foo"?

54. describe or context?

55. it or specify?

56. Don't get me wrong

57. None

58. So I decided to rebuild it

59. In a more adequat way

60. github.com/cyril/r_spec and I call it r_spec

61. None

62. Well, let’s try it!

63. app = 'OMGLOL' def app.equal?(*) true end require 'rspec' RSpec.describe

    app do it { expect(app).to be 42 } end

64. app = 'OMGLOL' def app.equal?(*) true end require 'rspec' RSpec.describe

    app do it { expect(app).to be 42 } end rspec 3-example/strange_app_spec.rb . Finished in 0.00097 seconds 1 example, 0 failures

65. What did you RSpec?

66. app = 'OMGLOL' def app.equal?(*) true end require 'rspec' RSpec.describe

    app do it { expect(app).to be 42 } end rspec 3-example/strange_app_spec.rb . Finished in 0.00097 seconds 1 example, 0 failures

67. app = 'OMGLOL' def app.equal?(*) true end require 'rspec' RSpec.describe

    app do it { expect(app).to be 42 } end rspec 3-example/strange_app_spec.rb . Finished in 0.00097 seconds 1 example, 0 failures Let’s fix that!

68. app = 'OMGLOL' def app.equal?(*) true end require 'rspec' RSpec.describe

    app do it { expect(app).to be 42 } end

69. app = 'OMGLOL' def app.equal?(*) true end require 'r_spec' RSpec.describe

    app do it { expect(app).to be 42 } end

70. app = 'OMGLOL' def app.equal?(*) true end require 'r_spec' RSpec.describe

    app do it { expect(app).to be 42 } end rspec 3-example/strange_app_spec.rb F 1. Failure: Expected "OMGLOL" to be 42. /Users/cyril/parisrb/3-example/strange_ app_spec.rb:10:in `block (2 levels) in <top (required)>' Ran 1 tests in 0.000195 seconds 0% compliant - 0 infos, 1 failures, 0 errors
71. None

72. Code in the slides github.com/cyril/parisrb

73. Any questions?

74. Happy specing!!!! github.com/fixrb fixrb.dev