
import unittest
import user_code
import ast
import re   
import unittest
import importlib
import io
from contextlib import redirect_stdout

class TestTask(unittest.TestCase):
    def test_returns_hash_string(self):
        import user_code
        importlib.reload(user_code)
        pw = "mySecretPassword123!"
        result = user_code.hash_password(pw)
        _dynamic_test(
            self,
            isinstance(result, str) and len(result) == 64,
            "Function returns a 64-character string hash",
            f"Expected a 64-character hash string, got: {result}",
        )

    def test_hash_is_not_password(self):
        import user_code
        importlib.reload(user_code)
        pw = "another$trongP@ss"
        result = user_code.hash_password(pw)
        _dynamic_test(
            self,
            result != pw,
            "Returned value is not the original password",
            f"Returned value should not be the input password, got: {result}",
        )

    def test_different_passwords_different_hashes(self):
        import user_code
        importlib.reload(user_code)
        pw1 = "passwordOne!"
        pw2 = "passwordTwo!"
        hash1 = user_code.hash_password(pw1)
        hash2 = user_code.hash_password(pw2)
        _dynamic_test(
            self,
            hash1 != hash2,
            "Different passwords produce different hashes",
            f"Expected different hashes for different passwords, got: {hash1} and {hash2}",
        )

    def test_same_password_same_hash(self):
        import user_code
        importlib.reload(user_code)
        pw = "constantPassword!"
        hash1 = user_code.hash_password(pw)
        hash2 = user_code.hash_password(pw)
        _dynamic_test(
            self,
            hash1 == hash2,
            "Same password always produces the same hash",
            f"Expected same hash for same password, got: {hash1} and {hash2}",
        )

    def test_password_not_stored_or_returned(self):
        # Check that the password is not returned and not present in the function output
        import user_code
        importlib.reload(user_code)
        pw = "NoStorePassword!"
        hash_val = user_code.hash_password(pw)
        _dynamic_test(
            self,
            pw not in hash_val,
            "Password is not present in the returned hash",
            f"Password should not appear in returned value, got: {hash_val}",
        )

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 Password Storage

Solution