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

class TestTask(unittest.TestCase):
    def test_requirements_txt_section(self):
        with open("user_code.py", "r") as f:
            code = f.read()
        has_pandas = "pandas-datareader==0.10.0" in code or "pandas_datareader==0.10.0" in code
        has_seaborn = "seaborn==0.13.2" in code
        _dynamic_test(
            self,
            has_pandas and has_seaborn,
            "requirements.txt section pins all third-party libraries",
            "requirements.txt section does not pin all required libraries or has wrong versions",
        )

    def test_documentation_for_vulnerabilities(self):
        with open("user_code.py", "r") as f:
            code = f.read()
        doc_lines = [line.strip() for line in code.splitlines() if ("vulnerab" in line.lower() or "advis" in line.lower())]
        _dynamic_test(
            self,
            any("vulnerab" in line.lower() for line in doc_lines),
            "Code includes documentation on how to check for vulnerabilities.",
            "Code does not include documentation on how to check for vulnerabilities.",
        )

    def test_only_allowed_libraries_imported(self):
        with open("user_code.py", "r") as f:
            code = f.read()
        allowed = ["pandas_datareader", "seaborn", "datetime"]
        import_lines = [line for line in code.splitlines() if line.strip().startswith("import") or line.strip().startswith("from")]
        only_allowed = all(any(lib in line for lib in allowed) for line in import_lines if not line.strip().startswith("#"))
        _dynamic_test(
            self,
            only_allowed,
            "Only allowed libraries are imported.",
            f"Found forbidden libraries in imports: {import_lines}",
        )

    def test_import_statements_match_pinned_names(self):
        with open("user_code.py", "r") as f:
            code = f.read()
        correct_pandas = ("import pandas_datareader as pdr" in code) or ("import pandas_datareader" in code)
        correct_seaborn = ("import seaborn as sns" in code) or ("import seaborn" in code)
        _dynamic_test(
            self,
            correct_pandas and correct_seaborn,
            "Import statements use exact library names as pinned in requirements.txt.",
            "Import statements do not match pinned library names.",
        )

    def test_fetch_financial_data_uses_pandas_datareader(self):
        with open("user_code.py", "r") as f:
            code = f.read()
        fetch_section = code.split("def fetch_financial_data")[1]
        uses_pandas = ("pandas_datareader" in fetch_section) or ("pdr.DataReader" in fetch_section) or ("pandas_datareader.DataReader" in fetch_section)
        _dynamic_test(
            self,
            uses_pandas,
            "fetch_financial_data uses pandas_datareader to fetch data.",
            "fetch_financial_data does not use pandas_datareader.",
        )

    def test_plot_data_uses_seaborn(self):
        with open("user_code.py", "r") as f:
            code = f.read()
        plot_section = code.split("def plot_data")[1]
        uses_seaborn = ("seaborn" in plot_section) or ("sns.lineplot" in plot_section)
        _dynamic_test(
            self,
            uses_seaborn,
            "plot_data uses seaborn to plot data.",
            "plot_data does not use seaborn.",
        )

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

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

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

Challenge: Safe Library Usage

Lösning

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Challenge: Safe Library Usage

Lösning