6. Static tools
• Inspect your code without launching it
•100% side effects free
•Easy to use
•Challenging to implement
•Rails DSL magic kills ‘em
•Ruby has no formal specification
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7. Runtime tools
• Inspect your code by launching it
•100% follow the way Ruby works
•Cope well with Rails DSL
•MAY have side effects
•Works until the very first failure
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9. Metrics
• Reek
– Uncommunicative name
– One char name
– Name ends with number
– Camelcase variable
– instance_of?, kind_of?, is_a? instead of
polymorphism
– Duplication
– Long class, method, parameter list
– Nested iterators
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10. Metrics
• Flog
– Assignment Branch Call metrics
• Saikuro
– Cyclomatic complexity
• Roodi
– Assignment in condition
– Missing else in case
– Long class/module/method
– Class/module/method name check
– Cyclomatic complexity
• Flay
– Duplicates
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11. Testing and Coverage tools
• RSpec
• Cucumber
• Autotest
• RCov, SimpleCov
• Continuous integration
• Heckle
– Change code (if <-> unless, calls, numbers,
assignments, etc.) to see if test fail
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13. What else can be done?
All these tools use Abstract Syntax Tree, but this is not
all the information that can be extracted!
The main problem is Ruby object model complexity
LEXICAL analysis
• Lexer -> Parser -> Abstract Syntax Tree -> Control
Flow Graph -> Data Flow Analysis
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14. RubyMine
• On the fly code inspections
• Code duplicates
• Test tools integration with graphical UI
• Coverage tool integration
• Everything is tightly integrated in IDE
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16. Thank you!
• Visit us http://www.jetbrains.com/ruby
• Read about http://blogs.jetbrains.com/ruby/
• Post bugs http://youtrack.jetbrains.net/issues/RUBY
• Follow us on twitter @rubymine
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