unitesting

1. Create a Test Class:
   • Define a class that inherits from unittest.TestCase. This class will contain your test methods (TestBinarySearch).
2. Test Methods:
   • Each test method is a function within the test class, starting with the prefix test_.
   • Test methods should assert specific conditions about the code. The unittest.TestCase class provides various assertion methods like
     • assertEqual,
     • assertNotEqual,
     • assertTrue,
     • assertFalse, etc.

Each test method (test_found, test_not_found, etc.) checks different scenarios of the binary search function.

1. Running Tests:
   • The if __name__ == '__main__': block runs the tests.
   • unittest.main() executes all the tests (as defined within your test class).

def binary_search(arr, target):
    # Initialize the low and high pointers
    low = 0
    high = len(arr) - 1
    
    # While the search space is valid
    while low <= high:
        # Find the middle index
        mid = (low + high) // 2
        
        # Check if the target is at the mid index
        if arr[mid] == target:
            return mid
        # If the target is greater than the mid element, ignore the left half
        elif arr[mid] < target:
            low = mid + 1
        # If the target is less than the mid element, ignore the right half
        else:
            high = mid - 1
    
    # Return -1 if the target is not found
    return -1

# Example
arr = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
target = 7
result = binary_search(arr, target)
if result != -1:
    print(f"Element {target} found at index {result}")
else:
    print(f"Element {target} not found in the list")

import unittest

def binary_search(arr, target):
    # ... (Your binary_search function code)

class TestBinarySearch(unittest.TestCase):
    def test_found(self):
        arr = [2, 3, 4, 10, 40]
        target = 10
        expected_index = 3
        self.assertEqual(binary_search(arr, target), expected_index)

    def test_not_found(self):
        arr = [2, 3, 4, 10, 40]
        target = 20
        expected_index = -1
        self.assertEqual(binary_search(arr, target), expected_index)

    def test_empty_array(self):
        arr = []
        target = 10
        expected_index = -1
        self.assertEqual(binary_search(arr, target), expected_index)

    def test_single_element(self):
        arr = [1]
        target = 1
        expected_index = 0
        self.assertEqual(binary_search(arr, target), expected_index)

    def test_target_at_beginning(self):
        arr = [1, 2, 3, 4, 5]
        target = 1
        expected_index = 0
        self.assertEqual(binary_search(arr, target), expected_index)

    def test_target_at_end(self):
        arr = [1, 2, 3, 4, 5]
        target = 5
        expected_index = 4
        self.assertEqual(binary_search(arr, target), expected_index)

if __name__ == '__main__':
    unittest.main()