Leaving Behind the Software History When Transitioning to Open-Source: Reasons and Implications

Transcript

1. Leaving Behind the Software History When
   Transitioning to Open-Source: Reasons and
   Implications
   @gustavopinto @igorsteinmacher @gerosa_marco
   

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9. The project deleted the software history and
   imported the source code all at once!
   

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10. Mihai Codoban, Sruti Srinivasa Ragavan, Danny Dig, and Brian Bailey.
    Software history under the lens: A study on why and how developers
    examine it. In ICSME 2015, pages 1–10, 2015.
    “Software history is indispensable for developers.
    Of the 217 developers surveyed in this work, 85% find software history
    important to their development activities and 61% need to refer to
    history at least several times a day.”
    More benefits:
    Knowledge acquisition (Pham et al., 2013)
    End-users take advantage of the software history (Kuttal et al., 2014)
    Research (co-changes, defect prediction, mining, etc.)
    

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11. Why one would
    remove the whole
    history? What are the
    reasons? and the
    implications?
    

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12. We found 50
    proprietary
    projects that
    made the shift
    to open source
    and deleted
    the history
    We could find only 8 projects that kept the history
    

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13. We found 50
    proprietary
    projects that
    made the shift
    to open source
    

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14. We found 50
    proprietary
    projects that
    made the shift
    to open source
    

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15. We found 50
    proprietary
    projects that
    made the shift
    to open source
    1. Why did you decide not to keep the software
    history?
    

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16. We found 50
    proprietary
    projects that
    made the shift
    to open source
    2. Do the core developers face any kind of problems
    with the lack of software history?
    

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17. We found 50
    proprietary
    projects that
    made the shift
    to open source
    3. Do the newcomers face any kind of problems with
    the lack of software history?
    

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18. We found 50
    proprietary
    projects that
    made the shift
    to open source
    4. How does the lack of software history impacted
    software evolution?
    

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19. We found 50
    proprietary
    projects that
    made the shift
    to open source
    15 did not answered our inquiries
    41 answers in total
    

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20. We found 50
    proprietary
    projects that
    made the shift
    to open source
    15 did not answered our inquiries
    

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21. We found 50
    proprietary
    projects that
    made the shift
    to open source
    15 did not answered our inquiries
    

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22. We found 50
    proprietary
    projects that
    made the shift
    to open source
    15 did not answered our inquiries
    

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23. We found 50
    proprietary
    projects that
    made the shift
    to open source
    15 did not answered our inquiries
    

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24. We found 50
    proprietary
    projects that
    made the shift
    to open source
    15 did not answered our inquiries
    

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25. RQ1. Why some projects do not open the software history?
    Extracting just the
    subfolder would have been
    difficult, and older versions
    would not have built
    First get something working,
    and then disentangle it from
    your own proprietary code,
    configuration, etc.
    Entangled with proprietary code
    Contains sensitive information
    Housekeeping needed
    License and legal reasons
    

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26. RQ1. Why some projects do not open the software history?
    The earliest commits may
    contain information we cannot
    share, so upon releasing we
    squashed the history
    Going through thousands of
    commits means no one will take on
    the heroic task of even open-
    sourcing the product
    Entangled with proprietary code
    Contains sensitive information
    Housekeeping needed
    License and legal reasons
    

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27. RQ1. Why some projects do not open the software history?
    We cleaned embarrassing or
    inappropriate comments,
    brought the code up to OSS
    standards …
    Entangled with proprietary code
    Contains sensitive information
    Housekeeping needed
    License and legal reasons
    

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28. RQ1. Why some projects do not open the software history?
    Made it much easier to get
    the lawyers at our parent
    company to agree to open
    source it
    Instead of reviewing the
    entire history, they could
    review just the current state
    Entangled with proprietary code
    Contains sensitive information
    Housekeeping needed
    License and legal reasons
    

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29. RQ2. What are the challenges to deal with a history free project?
    None of the core developers
    has wanted or needed to go
    look back through the
    history
    Communication, documentation,
    and idiomatic expressions of the
    Python code are sufficient to
    maintain project coherency
    

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30. RQ2. What are the challenges to deal with a history free project?
    We still use the non-git
    system internally and can
    refer to history if we need to
    I’m probably the person
    most likely to access it,
    and I’d estimate that I use
    it only a few times per year
    

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31. RQ2. What are the challenges to deal with a history free project?
    For a fast-moving project, history
    from more than half a year ago is
    not particularly valuable for
    development
    I am not aware of any problems for
    newcomers
    The lack of software history does
    not greatly impact software
    evolution and understanding
    

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32. Open challenges
    How to design tools to leverage and visualize the software history?
    How to improve tools to migrate code between repositories and to
    disentangle source code
    How to find sensitive information in the software history?
    How to estimate the cost of releasing the history?
    When do developers need to understand the software history?
    

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34. Leaving Behind the Software History When
    Transitioning to Open-Source: Reasons and
    Implications
    @gustavopinto @igorsteinmacher @gerosa_marco
    

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