Feat: calculator implementation

src/calculator.py

@@ -10,3 +10,46 @@
 #   Multiplication: 8
 #   Division: 2
 #
+import enum
+
+class OperationType(enum.Enum):
+    SUM = 1
+    DIFFERENCE = 2
+    MULTIPLICATION = 3
+    DIVISION = 4
+
+def sum(a, b):
+    return a + b
+
+def difference(a, b):
+    return a - b
+
+def multiplication(a, b):
+    return a * b
+
+def division(a, b):
+    if b != 0:
+        return a / b
+    else:
+        raise ValueError("Error: Division by zero")
+
+def operation(a, b, op: OperationType):
+    if op == OperationType.SUM:
+        return sum(a, b)
+    elif op == OperationType.DIFFERENCE:
+        return difference(a, b)
+    elif op == OperationType.MULTIPLICATION:
+        return multiplication(a, b)
+    elif op == OperationType.DIVISION:
+        return division(a, b)
+    else:
+        raise ValueError("Invalid operation")
+
+if __name__ == "__main__":
+    num1 = float(input("Insert first number: "))
+    num2 = float(input("Insert second number: "))
+
+    print(f"SUM: {operation(num1, num2, OperationType.SUM)}")
+    print(f"Difference: {operation(num1, num2, OperationType.DIFFERENCE)}")
+    print(f"Multiplication: {operation(num1, num2, OperationType.MULTIPLICATION)}")
+    print(f"Division: {operation(num1, num2, OperationType.DIVISION)}")

tests/test_calculator.py

@@ -0,0 +1,44 @@
+from src.calculator import operation, OperationType
+
+def test_calculator_operations() -> None:
+    assert operation(4, 2, op=OperationType.SUM) == 6  # SUM
+    assert operation(4, 2, op=OperationType.DIFFERENCE) == 2  # DIFFERENCE
+    assert operation(4, 2, op=OperationType.MULTIPLICATION) == 8  # MULTIPLICATION
+    assert operation(4, 2, op=OperationType.DIVISION) == 2  # DIVISION
+    try:
+        operation(4, 0, op=OperationType.DIVISION)
+    except ValueError as e:
+        assert str(e) == "Error: Division by zero"  # DIVISION by zero
+    try:
+        operation(4, 2, op=None)  # Invalid operation
+    except ValueError as e:
+        assert str(e) == "Invalid operation"
+
+def test_calculator_main() -> None:
+    import builtins
+    import io
+    import sys
+
+    input_values = ["4", "2"]
+    output = io.StringIO()
+    sys.stdout = output
+
+    def mock_input(s):
+        return input_values.pop(0)
+
+    builtins.input = mock_input
+
+    # Re-import the main module to run the main function
+    import src.calculator as calculator_module
+
+    # Restore stdout
+    sys.stdout = sys.__stdout__
+
+    expected_output = (
+        "Insert first number: Insert second number: SUM: 6.0\n"
+        "Difference: 2.0\n"
+        "Multiplication: 8.0\n"
+        "Division: 2.0\n"
+    )
+
+    assert output.getvalue() == expected_output