Code Coverage by Sachin Vas

Swift Bangalore Chapter #18

Transcript

1. CODE COVERAGE
   Sachin Vas, Halodoc
   

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3. AGENDA
   ▸ CI/CD PIPELINES
   ▸ CODE COVERAGE
   ▸ XCODE IDE SUPPORT
   ▸ LLVM CODE COVERAGE
   

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4. Code Merge
   Build Unit Test Integration Test
   Code Review Staging Production
   CI Pipeline
   CD Pipeline
   

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5. CI/CD
   ▸ Merges changes to main branch as often as possible
   ▸ Validates changes using automated tests
   ▸ Added advantage over delayed merges which usually
   ends up in integration hell
   ▸ Always checks newer commits doesn’t break any of the
   existing code
   CI PIPELINE
   

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6. CI/CD
   ▸ Extension on the previous step
   ▸ Release new changes quickly in a sustainable way
   ▸ Deploy at your convenience time (daily, weekly, fortnightly)
   ▸ Best practice is to rollout updates in small batches for ease
   troubleshooting any production issues.
   ▸ Continuous Deployment is the automatic version of
   Continuous Delivery.
   CD PIPELINE
   

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7. CODE COVERAGE
   ▸ What
   ▸ Why
   ▸ How
   ▸ Types
   CODE COVERAGE
   

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8. CODE COVERAGE
   ▸ Percentage of code covered by automated tests
   ▸ Determines which statements are executed
   ▸ Part of feedback loop
   WHAT?
   

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9. CODE COVERAGE
   ▸ Our tests actually test our code
   ▸ Do we have enough testing in place
   ▸ Maintain Test Quality over the lifetime of a project
   WHY?
   

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10. CODE COVERAGE
    ▸ Source Code Instrumentation
    ▸ Intermediate Code Instrumentation
    ▸ Runtime Information collection
    HOW?
    

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11. CODE COVERAGE
    ▸ Statement
    ▸ Branch
    ▸ Function
    TYPES
    

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12. CODE COVERAGE
    CODE COVERAGE PERCENTAGE
    

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13. CODE COVERAGE
    ▸ Built into the IDE
    ▸ Provides line coverage metrics
    ▸ You can exercise your frameworks (only open source files)
    ▸ You can customise running certain TestBundles on Certain
    Targets
    XCODE CODE COVERAGE
    

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14. CODE COVERAGE
    DEMO
    

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15. LLVM-COV
    ▸ llvm-cov
    ▸ Provides 4 types of code coverage
    ▸ Sub commands for meaningful statistics
    ▸ Custom script to generate coverage
    ▸ Provides similar reports as Jacuco.
    LLVM CODE COVERAGE
    

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16. LLVM-COV
    ▸ llvm-profdata
    ▸ Merge multiple Profile Data Files
    ▸ Useful if you have multiple in-house frameworks
    LLVM PROFDATA COVERAGE
    

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17. LLVM-COV
    DEMO
    

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18. CODE COVERAGE
    ▸ Ensure every Public Method is covered
    ▸ Increase Code Coverage for each Public Method
    ▸ Cover Conditionals
    ▸ Prefer Branch Coverage over other types
    RECOMMENDATION
    

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19. CODE COVERAGE
    https://developer.apple.com/library/archive/documentation/DeveloperTools/Conceptual/testing_with_xcode/chapters/
    07-code_coverage.html
    https://clang.llvm.org/docs/SourceBasedCodeCoverage.html
    https://llvm.org/docs/CommandGuide/llvm-cov.html
    https://llvm.org/docs/CommandGuide/llvm-profdata.html
    REFERENCES
    

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