PHP Testing and Mocking

Transcript

1. PHP Testing and Mocking
   Some techniques and quirks.
   Farzad Ghanei
   

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2. On Testing
   Tests Help to
   ● keep the code base under control
   ● have more modular and well structured code
   ● new team members to be productive sooner
   ● team members to stay productive
   

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3. On Testing
   Writing tests is a necessity
   

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4. ● Test expected behaviors, focus on “what” than “how”
   ● Treat tests as live documentation
   ● Let the test describe the expected behavior
   ● Fail the test first, then pass them
   On Writing Tests
   

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5. On Mocking
   ● Mocking helps to handle dependencies
   ● Mocking helps tests be focused
   ● Mocking can help tests to run faster by abstracting external resources
   

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6. On Mocking
   ● Mocking is a good technique
   ● Beware of too much mocking
   

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7. Some Testing Techniques
   ● Use data providers
   ● Setting expected exception before the call to tests
   ● Anonymous function for complex param assertion (returnCallback())
   ○ with(‘p1’, ‘p2’) / withConsecutive([[‘p1’, ‘p2’], [‘p21’, ‘p22’]])
   ● Anonymous functions for complex expected returns (returnCallback())
   ○ $this->willReturn(‘foo’) / $this->will($this->return(‘foo’))
   ○ $this->will(returnArgument(0) / onConsecutiveCalls([‘r1’, ‘r2’]) / returnValueMap([‘p1’, ‘p2’, ‘r’]))
   

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8. PHPUnit Mocking
   ● Mock existing classes
   ● Partial mocking
   ● Expectations
   ○ Call count
   ○ Params
   ● ...
   

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9. Some PHPUnit Mocks Quirks
   ● PHPUnit mocks and Hack
   ● PHPUnit mocks in data providers
   

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10. Let’s see some code
    

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11. Mockery
    ● Mock any class/function
    ● Partial mocking
    ● Expectations
    ○ Call count
    ○ Params
    ● Integration with PHPUnit (test
    runner)
    ● ...
    

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12. Some Mockery Quirks
    ● Integration with PHPUnit (test runner)
    ● No call count, means no call is OK
    ● Mocking not existing classes (prefer partial)
    ● Mocking method calls in order
    ○ Mocking method multiple times won’t work
    ○ Can use callback function
    ● Some equality assertions need explicit Hamcrest checks (like HHVM
    collections)
    

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13. More code ...
    

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14. ● Make tests fail, then pass them
    ● Use mocking when helps
    ● Benefit from data providers
    ● Exception assertion closest to expected place
    ● Be aware of the quirks
    Summary
    

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