
import unittest
import user_code
import ast
import re   
import unittest
import importlib
import user_code

class TestTask(unittest.TestCase):
    def test_valid_division(self):
        importlib.reload(user_code)
        result = user_code.divide_numbers(10, 2)
        _dynamic_test(
            self,
            result == 5.0,
            "Correct result returned for valid division (10/2)",
            f"Expected 5.0, got {result}",
        )

    def test_zero_division(self):
        importlib.reload(user_code)
        result = user_code.divide_numbers(10, 0)
        _dynamic_test(
            self,
            isinstance(result, str) and result == "An error occurred. Please check your input.",
            "Correct error message for division by zero",
            f"Expected error message for division by zero, got {result}",
        )

    def test_type_error(self):
        importlib.reload(user_code)
        result = user_code.divide_numbers(10, "x")
        _dynamic_test(
            self,
            isinstance(result, str) and result == "An error occurred. Please check your input.",
            "Correct error message for type error",
            f"Expected error message for type error, got {result}",
        )

    def test_no_internal_details(self):
        importlib.reload(user_code)
        result = user_code.divide_numbers(10, 0)
        _dynamic_test(
            self,
            "ZeroDivisionError" not in result and "Traceback" not in result and "division by zero" not in result,
            "No internal details are leaked in error message (ZeroDivisionError)",
            f"Internal details leaked in error message: {result}",
        )
        result2 = user_code.divide_numbers(10, "x")
        _dynamic_test(
            self,
            "TypeError" not in result2 and "Traceback" not in result2 and "unsupported operand" not in result2,
            "No internal details are leaked in error message (TypeError)",
            f"Internal details leaked in error message: {result2}",
        )

def _dynamic_test(test_case, condition, success_message, failure_message):
    if condition:
        test_case._testMethodName = success_message
        test_case.assertTrue(True, success_message)
    else:
        test_case._testMethodName = failure_message
        test_case.fail(failure_message)

def normalize_text(text):
    text = text.lower()
    text = re.sub(r"\\s{2,}", " ", text)
    text = re.sub(r"\\s*([,:?])\\s*", r"\\1 ", text)
    return text.strip()

def change_var(code: str, var_name: str, value: str) -> str:
    tree = ast.parse(code)
    lines = code.splitlines()
    changed = False
    # Collect all assignment nodes to modify
    assign_nodes = [
        (i, node)
        for i, node in enumerate(tree.body)
        if isinstance(node, ast.Assign)
        and any(isinstance(target, ast.Name) and target.id == var_name for target in node.targets)
    ]

    # If nothing to change, return unmodified code
    if not assign_nodes:
        return code

    # Perform replacements for all matching assignments (from last to first to not break line offsets)
    for i, node in reversed(assign_nodes):
        start_line = node.lineno - 1
        line = lines[start_line]
        indent = ' ' * (len(line) - len(line.lstrip()))
        lines[start_line] = f"{indent}{var_name} = {value}"
        next_line = len(lines)
        for next_node in tree.body[i+1:]:
            if hasattr(next_node, 'lineno'):
                next_line = next_node.lineno - 1
                break
        if next_line > start_line + 1:
            lines[start_line+1:next_line] = []
        changed = True

    return '\\n'.join(lines) if changed else code

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


test_main.py

Learn how to write secure Python code by understanding common vulnerabilities, safe coding techniques, and practical security measures. This course covers essential security concepts, real-world scenarios, and hands-on tasks to help you protect your Python applications.

Explore the most common security pitfalls in Python, how vulnerabilities arise, and the foundational principles for writing secure code.

Master secure coding techniques to prevent vulnerabilities and ensure robust Python applications.

Learn how to handle, store, and process sensitive data securely in Python applications.

Challenge: Secure Exception Handling

Solution