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Q.04 of 32

What is the AAA pattern in unit testing?

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AAA stands for Arrange, Act, Assert - a common pattern for structuring unit tests:

  • Arrange: Set up test data, mocks, and preconditions
  • Act: Execute the method or function being tested
  • Assert: Verify the expected outcome
test('calculateDiscount returns correct discount amount', () => {
  // Arrange
  const price = 100;
  const discountPercent = 10;
  
  // Act
  const result = calculateDiscount(price, discountPercent);
  
  // Assert
  expect(result).toBe(10);
});
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