How to write good bash code using TDD?

1. Understand the bash pitfalls
2. Use shellcheck
3. Emphasise on functional code
4. Discover the simplest concepts
5. Explore their optimal composition
6. Use containers for integration testing
7. Stop when the fun stops

https://github.com/gerhard/bash is meant to capture the mechanics and reasoning behind test-driven bash code. It also conveys the process behind evolving a good bash codebase.

Transcript

1. TDD #!/bin/bash
   

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2. $ false
   $ echo $?
   1
   $ true
   $ echo $?
   0
   $ :
   $ echo $?
   0
   

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3. test
   

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4. $ test -f ./missing
   $ echo $?
   1
   $ [ -f ./missing ]
   $ echo $?
   1
   

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5. [[ ]]
   

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6. $ [[ foobar =~ bar ]]
   $ echo $?
   0
   $ [[ foobar =~ ^bar ]]
   $ echo $?
   1
   

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7. ||
   

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8. $ cf push &>/dev/null
   $ echo $?
   1
   $ cf push >&- || echo "Call 222333"
   Call 222333
   $ echo $?
   0
   

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9. if
   

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10. if cf push >&-
    then
    true
    else
    echo "Call 222333"
    fi
    if ! cf push >&-
    then
    echo "Call 222333"
    fi
    

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11. The TDD Apostate1
    1 Mark Seemann
    

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12. TDD != good code
    

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13. How to write
    good bash code?
    

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14. github.com/gerhard/bash
    

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15. The path to
    good bash code
    

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16. Understand the bash pitfalls
    

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17. Use shellcheck
    

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18. Emphasise on functional code
    

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19. Discover the simplest concepts
    

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20. Explore their optimal composition
    

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21. Stop when the fun stops
    

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22. Contain that bash
    

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23. Functional core, imperative shell2
    2 Gary Bernhardt, Boundaries, SCNA & Ruby Conf 2012
    

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24. Containers for integration testing
    

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25. github.com/gerhard/bash
    

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