Automated Testing

Automated testing is the most critical quality gate in a CI/CD pipeline. Without reliable tests, you cannot confidently ship changes. This lesson covers testing levels, strategies, and how to integrate tests into your pipeline.

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Why Automated Testing?

Manual testing is:

• Slow — humans take minutes to hours
• Error-prone — repetitive tasks lead to mistakes
• Unscalable — cannot run on every commit
• Expensive — requires dedicated QA time

Automated testing is:

• Fast — thousands of tests in seconds
• Consistent — same result every time
• Scalable — runs on every push, every PR
• Cheap — once written, runs forever

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The Testing Pyramid

The testing pyramid is a widely accepted model for balancing different types of tests:

         ╱╲
        ╱ E2E ╲          Few, slow, expensive
       ╱────────╲
      ╱Integration╲      Some, moderate speed
     ╱──────────────╲
    ╱   Unit Tests   ╲   Many, fast, cheap
   ╱──────────────────╲