Test driven development (TDD) continues to grow in popularity as a development process that promotes diligence, oversight, and robust programming practices. In fact, in our recent Open Source Survey, nearly half of respondents stated that they used TDD as one of their core development processes. Whether for new or legacy projects, TDD is becoming increasingly critical to how large enterprises develop and maintain applications. This feedback coupled with requests from Python developers led to the inclusion of key TDD modules in our most recent release of ActivePython. (To learn more about the latest ActivePython releases, 2.7.12 & 3.5.2, check out this blog.) In this webinar, Tom Radcliffe (ActiveState Director of Engineering) and Jeff Rouse (ActiveState Director of Product Management) discuss the emergence and importance of TDD, how it impacts Python developers, and what it means for enterprise programming. Some of the key topics they’ll cover include: - What is TDD and how can it be implemented successfully - Why is ActivePython well suited to TDD - How can enterprises benefit from TDD - And more!

1. Jeff Rouse, Director of Product Management, ActiveState
Tom Radcliffe, Director of Engineering, ActiveState
Test Driven Development with
ActivePython
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2. Today’s Speakers
Jeff Rouse
Director of Product Management
ActiveState
Tom Radcliffe
Director of Engineering
ActiveState
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3. Agenda
> What is Test Driven Development (TDD)?
> How to successfully implement TDD
> Why is ActivePython well suited to TDD?
> How can enterprises benefit from TDD?
> Q/A
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4. What is TDD?
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5. Tests Before Code
> Don’t write a line of new code unless you first
have a failing automated test
> Eliminate duplication
Red: test fails
Green: test passes but code is a mess
Refactor: clean up that mess!
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6. TTD Workflow
> Requirements [What]
> Specifications [How]
> “Design:”
> Automated test for a specification
> Code to pass
> Refactor
> Iterate
=> Small steps, organic design
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7. “Eliminate Duplication”
Every piece of information in an application
should be represented exactly once.
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8. Pros of TDD
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> Brings dev closer to the user
> Requirement questions found faster
> Makes you trust your code
> Make changes with confidence
> Fix bugs once
> Easier to handle errors/bugs initially
> Reduces bugs throughout the system

9. Cons of TDD
> Larger code base
> Stiffness (harder to change)
> Test maintenance takes time
> Easy to go too far (100% code coverage?!)
> Mocks, dependency injection, complexity…
> Not a replacement for integration tests
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10. More TDD Goodness
> Know the finish line!
> Increases team ownership - trust!
> Tests supplement the docs
> Makes onboarding new devs easier
> Greater confidence in changes allows a quicker
release cadence (CD!)
> More time spent delivering value
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11. > Test Driven Development
was the most popular
methodology in our 2016
Open Source Languages
Survey
> 867 respondents
> 49% using TDD
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12. How to successfully
implement TDD
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13. Attitude + Automation
> Must have committed attitude
> Integrate testing with routine workflow
> Automate everything
> Metaprogramming
“Virtue is not an act, it is a habit”
-- Aristotle on software
development best practices
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14. Things to Look Out For
> Embedded assumptions
> Overly narrow/concrete tests
> Needs of testing taking over design
> Layered algorithms vs inversion of control
> Sometimes the only way to understand the
problem is to write the code
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15. ActivePython & TDD
> Careful with those types!
> Strong language support for tests
> Active communities around several testing
packages supporting a variety of testing needs
& goals
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16. Unittest
> Part of Python standard library since Python 2.1
> Still under active development
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17. Pytest
> Most full featured and popular of third party
packages
> Can run unittest and nose tests
> Our recommended testing package
> Great support for fixtures
> Plugins for other frameworks (ex. Django,
Twisted, Pyflakes)
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18. Pyflakes
> Code quality checks w/ your testing
> Analyzes your source for errors
> Low false positive rate
> Does not check for style
> Good speed
> Can run from pytest
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19. Coverage
> Monitors test execution in real time
> Combined with tests tells you what code is
never tested
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20. Other Testing Packages
> nose/nose2: test-runner
> pyresttest: testing REST APIs
> selenium: Web browser testing
> doctest: std. library, tests via code comments
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21. Future of TDD
> Metaprogramming
> Improved language support
> Functional programming
> More automation/intelligence
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22. ActivePoll:
Do you currently or plan to employ
TDD using Python?
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23. Why is ActivePython well
suited to TDD?
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24. Included Testing Modules
> Pytest
> Coverage
> Pyflakes
(+Unittest)
Plus many of the most popular Python developer
packages.
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25. Enterprise ActivePython Benefits
> More reliable delivery
> Integrated OpenSSL +updates
> More maintainable code
> Commercial support/SLAs
> Compliance, indemnification
> Custom packages
> Language upgrades!
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26. Developer ActivePython Benefits
> Turn-key installation
> Cross-platform support
> Extra “batteries included”
> All major language versions
> All major platforms
> Code recipes
> Thorough documentation
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27. ActivePython Custom Packages
Promo!
Purchase ActivePython Enterprise Edition in February
2017 and receive custom packages for free.
Email us for more details
solutions@activestate.com

28. ActiveState News
> ActivePython 2.7.13 & 3.5.2 released
> Komodo IDE + ActivePython...together at last!
> Another ActivePython release later in Q1!
> ActiveGo - also this quarter
> ActiveRuby - releasing Q2
> ActiveNode & ActiveLua arriving later in 2017
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29. Upcoming Events
> Pycon 2017 - May 17-25 in Portland, OR
> OSCON 2017 - May 8-11 in Austin, TX
> Look for another ActivePython webinar in Q2

30. New Language Distributions
> Sign up for more
information:
> www.activestate.com/Ruby
> www.activestate.com/Go
> www.activestate.com/Node
> www.activestate.com/Lua
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31. Q/A
Download ActivePython!
activestate.com/activepython/downloads
Contact us if you have questions:
jeffr@activestate.com
support@activestate.com
sales@activestate.com
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