Testing Outside of the Ruby World

Transcript

1. T O
   f
   R b W r
   Joseph Wilk
   

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2. W ’
   R b f r ?
   

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3. S r ...
   N R b .
   R .
   

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4. S
   “The number of languages you know
   corresponds to your programming
   skill”
   

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5. JUnit
   Rspec
   PHPSpec
   JSpec
   Circumspec
   SomethingSpec
   Y ... T
   ScrewUnit
   JBehave
   Jasmine
   Cucumber
   BlahSpec
   WhateverSpec
   

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6. JUnit
   Rspec
   PHPSpec
   JSpec
   Circumspec
   SomethingSpec
   Y ... T
   ScrewUnit
   JBehave
   Jasmine
   Cucumber
   BlahSpec
   WhateverSpec
   BORING!
   

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7. T & M
   Java
   Ruby
   Monkey.stub!(:new).and_return(mock("monkey"))
   I owe you one Java mocking example.
   I don’t have the will power to write it.
   Sorry.
   

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8. T & M
   Java
   Ruby
   Monkey.stub!(:new).and_return(mock("monkey"))
   I owe you one Java mocking example.
   I don’t have the will power to write it.
   Sorry.
   BORING!
   

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9. I r
   Asynchronous Property testing
   Model testing
   Permutation
   explosions
   Test feedback
   Metrics
   Graphical tests
   

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10. H
    Curry
    

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11. “Program testing can be used to show the
    presence of bugs, but never to show their
    absence!”
    Edsger Dijkstra
    

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12. Q C
    Properties
    ˲TMFOHUI GJWF@SBOEPN@DIBSBDUFST T
    
    
    For all values of s the length of the thing
    returned by five_random_characters is 5
    

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13. Q C
    Logic
    Randomly
    generate
    tests
    Function
    Function
    Properties
    QuickCheck
    

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14. Q C
    Logic
    Randomly
    generate
    tests
    Function
    Function
    Properties
    QuickCheck
    

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15. Q C
    Logic
    Randomly
    generate
    tests
    Function
    Function
    Properties
    QuickCheck
    

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16. Q C
    Logic
    Randomly
    generate
    tests
    Function
    Properties
    QuickCheck
    

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17. Q C
    Logic
    Randomly
    generate
    tests
    Function
    Properties
    QuickCheck
    Counter
    Examples
    

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18. Q C
    Properties
    it "should reverse a string" do
    "monkeys".reverse.reverse.should == "monkeys"
    end
    100.times.map {“#{rand(10)}#{rand(10)}”}.each do |char|
    it "should reverse a string" do
    char.reverse.reverse.should == char
    end
    end
    

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19. Q C
    import Data.Char
    import Test.QuickCheck
    instance Arbitrary Char where
    arbitrary = choose ('\32', '\128')
    coarbitrary c = variant (ord c `rem` 4)
    prop_RevRev xs = reverse (reverse xs) == xs
    where types = xs::[Char]
    Properties
    $ Main> quickCheck prop_RevRev
    OK, passed 100 tests.
    

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20. Er
    Messaging/
    Concurrency
    

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21. Erlang
    runtime
    system
    McErlang
    runtime
    system
    M Er
    Models
    communication
    concurrency
    distribution
    

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22. M Er
    Models
    Messenger
    Service
    Message
    client
    Message
    client
    Fred Clara
    message
    “Scottish
    fiction”
    “Scottish
    fiction”
    login login
    

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23. M Er
    if user1 does not send a message m to user2 until user2 is logged on,
    then
    if user1 does send a message m to user2
    then
    eventually user2 receives the message m.
    "not P until Q => (eventually P => eventually R)”
    P: clara sends message “Scottish fiction” to fred
    Q: fred is logged on
    R: fred receives the message “Scottish fiction” from clara
    Models
    

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24. M Er
    Models
    {program={scenario,start,[[
    [{logon,clara},{message,fred,"hi"},logoff],
    [{logon,fred},logoff]]]},
    monitor={mce_ltl_parse:ltl_string2module_and_load
    ("not P until Q implies (eventually P implies
    eventually R)", messenger_mon),
    {void,[{'P',basicPredicates:message_to
    (clara,fred,"hi")},
    {'Q',basicPredicates:logon(fred)},
    {'R',basicPredicates:message_received
    (fred,clara,"hi")}]}},
    algorithm={mce_alg_buechi,void}}).
    

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25. “Every method you use to prevent or find
    bugs leaves a residue of subtler bugs against
    which those methods are ineffectual
    Pesticide Paradox / Beizer
    

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26. C r
    Bracket
    hell
    

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27. (fact
    (alive-in-next-generation? ...cell...) => truthy
    (provided
    (alive? ...cell...) => false
    (neighbor-count ...cell...) => 3))
    M
    Facts
    cell = mock("a cell")
    cell.stub(:alive?).and_return(false)
    cell.stub(:neighbour_count).and_return(3)
    cell.alive_in_next_generation.should == true
    

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28. I
    Brief visit
    

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29. I
    Specs are documentation
    

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30. I
    Specs are documentation
    

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31. J v S r p
    Without
    the Java
    

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32. Z b .
    Trapped inside a browser
    

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33. Z b .
    Trapped inside a browser
    var zombie = require("zombie");
    var assert = require("assert");
    zombie.visit("http://localhost:3000/",
    function (err, browser, status) {
    browser.
    fill("email", "zombie@underworld.dead").
    pressButton("Sign Me Up!",
    function(err, browser, status) {
    assert.equal(browser.text("title"), "Welcome");
    })
    });
    

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34. V w
    Topics
    { topic: function () { return 42 },
    'should be a number': function (topic) {
    assert.isNumber (topic);
    },
    'should be equal to 42': function (topic) {
    assert.equal (topic, 42);
    }
    }
    

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35. V w
    Asynchronous calls
    { topic: function () {
    fs.stat('~/FILE', this.callback);
    },
    'can be accessed': function (err, stat) {
    assert.isNull (err); // We have no error
    assert.isObject (stat); // We have a stat object
    },
    'is not empty': function (err, stat) {
    assert.isNotZero (stat.size); // The file size is > 0
    }
    }
    

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36. V w
    Promises / Futures
    { topic: function () {
    var promise = new(events.EventEmitter);
    fs.stat('~/FILE', function (e, res) {
    if (e) { promise.emit('error', e) }
    else { promise.emit('success', res) }
    });
    return promise;
    },
    'can be accessed': function (err, stat) {
    assert.isNull (err); //We have no error
    assert.isObject (stat); //We have a stat object
    },
    'is not empty': function (err, stat) {
    assert.isNotZero (stat.size); //The file size is > 0
    }
    }
    

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37. V w
    Parallel Execution
    { '/dev/stdout': {
    topic: function () { path.exists('/dev/stdout',this.callback) },
    'exists': function (result) { assert.isTrue(result) }
    },
    '/dev/tty': {
    topic: function () { path.exists('/dev/tty',this.callback) },
    'exists': function (result) { assert.isTrue(result) }
    },
    '/dev/null': {
    topic: function () { path.exists('/dev/null',this.callback) },
    'exists': function (result) { assert.isTrue(result) }
    }
    }
    

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38. Permutation Explosion
    T Sw r
    

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39. Permutation Explosion
    T Sw r
    

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40. J v
    Really
    

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41. J M
    Faster Test feedback
    Lots of very short tests
    A few very long ones
    Failures are not
    randomly distributed
    Kent Beck
    

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42. J M
    Faster Test feedback
    

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43. I r L
    Learn from Metrics
    

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44. O r ff
    dessert
    

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45. ‘‘What is the use of a book,’’ thought Alice,
    ‘‘without pictures or conversations?’’
    Lewis Carroll
    Alice’s Adventures in Wonderland
    

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46. Sw L
    Words are not enough
    Ward Cunningham
    

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47. Ward Cunningham
    http://vimeo.com/22165070
    

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48. Gr p T
    Brian Marick
    

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49. http://testobsessed.com/wp-content/uploads/2007/02/testheuristicscheatsheetv1.pdf
    ‘‘How much do you know about the
    heuristics of failure?’
    Joseph Wilk
    Scotland Ruby Conf 2011
    

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50. T I
    

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51. !
    Joseph Wilk
    @josephwilk
    http://blog.josephwilk.net
    

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