
import unittest
import user_code
import ast
import re   
import importlib
import csv
import unittest
import importlib
import pandas as pd
import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as plt

class TestTask(unittest.TestCase):
    def setUp(self):
        self.user_code = importlib.import_module('user_code')
        self.data = [
            {'date': '2024-01-15', 'type': 'deposit', 'amount': 2000},
            {'date': '2024-01-20', 'type': 'withdrawal', 'amount': 500},
            {'date': '2024-02-10', 'type': 'deposit', 'amount': 2200},
            {'date': '2024-02-12', 'type': 'withdrawal', 'amount': 300},
            {'date': '2024-03-05', 'type': 'deposit', 'amount': 2500},
            {'date': '2024-03-17', 'type': 'withdrawal', 'amount': 700},
            {'date': '2024-03-30', 'type': 'deposit', 'amount': 1000},
            {'date': '2024-01-25', 'type': 'deposit', 'amount': 1800},
            {'date': '2024-02-18', 'type': 'withdrawal', 'amount': 1000},
        ]
        self.df = pd.DataFrame(self.data)

    def test_grouping_and_summing(self):
        # Check that grouping and summing is correct
        importlib.reload(self.user_code)
        df = self.df.copy()
        # Run function but intercept plt.show
        plt.clf()
        orig_show = plt.show
        plt.show = lambda: None
        self.user_code.plot_monthly_transaction_volumes(df)
        # Reproduce expected
        df['date'] = pd.to_datetime(df['date'])
        df['month'] = df['date'].dt.to_period('M').astype(str)
        monthly = df.groupby(['month', 'type'])['amount'].sum().unstack(fill_value=0)
        expected_months = ['2024-01','2024-02','2024-03']
        expected_deposits = [3800, 2200, 3500]
        expected_withdrawals = [500, 1300, 700]
        # Get plotted lines
        ax = plt.gca()
        lines = ax.get_lines()
        found_months = False
        found_deposits = False
        found_withdrawals = False
        # Check that lines match expected x/y
        for line in lines:
            xdata = list(line.get_xdata())
            ydata = list(line.get_ydata())
            label = line.get_label().lower()
            if xdata == expected_months:
                found_months = True
            if label == 'deposits' and ydata == expected_deposits:
                found_deposits = True
            if label == 'withdrawals' and ydata == expected_withdrawals:
                found_withdrawals = True
        _dynamic_test(self, found_months, "Months on x-axis are correct", "Months on x-axis are not correct")
        _dynamic_test(self, found_deposits, "Deposit totals per month are correct", "Deposit totals per month are not correct")
        _dynamic_test(self, found_withdrawals, "Withdrawal totals per month are correct", "Withdrawal totals per month are not correct")
        plt.show = orig_show
        plt.clf()

    def test_handles_missing_data(self):
        # Remove all withdrawals from March, should show 0 for withdrawals in March
        importlib.reload(self.user_code)
        df = self.df.copy()
        df = df[~((df['type']=='withdrawal') & (df['date'].str.startswith('2024-03')))]
        plt.clf()
        orig_show = plt.show
        plt.show = lambda: None
        self.user_code.plot_monthly_transaction_volumes(df)
        ax = plt.gca()
        found_zero_withdrawal = False
        for line in ax.get_lines():
            label = line.get_label().lower()
            xdata = list(line.get_xdata())
            ydata = list(line.get_ydata())
            if label == 'withdrawals' and 0 in ydata:
                found_zero_withdrawal = True
        _dynamic_test(self, found_zero_withdrawal, "Handles missing withdrawal data with zero", "Does not show zero for missing withdrawal month")
        plt.show = orig_show
        plt.clf()

    def test_plot_labels_and_legend(self):
        importlib.reload(self.user_code)
        df = self.df.copy()
        plt.clf()
        orig_show = plt.show
        plt.show = lambda: None
        self.user_code.plot_monthly_transaction_volumes(df)
        ax = plt.gca()
        xlabel = ax.get_xlabel()
        ylabel = ax.get_ylabel()
        title = ax.get_title()
        legend = ax.get_legend()
        legend_labels = [t.get_text().lower() for t in legend.get_texts()] if legend else []
        _dynamic_test(self, xlabel and 'month' in xlabel.lower(), "X-axis labeled with 'Month'", "X-axis label is missing or incorrect")
        _dynamic_test(self, ylabel and 'amount' in ylabel.lower(), "Y-axis labeled with 'Total Amount'", "Y-axis label is missing or incorrect")
        _dynamic_test(self, title and 'monthly' in title.lower(), "Plot has a title with 'Monthly'", "Plot title is missing or incorrect")
        _dynamic_test(self, 'deposits' in legend_labels and 'withdrawals' in legend_labels, "Legend includes both 'Deposits' and 'Withdrawals'", "Legend does not include both 'Deposits' and 'Withdrawals'")
        plt.show = orig_show
        plt.clf()

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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Challenge: Plot Monthly Transaction Volumes

Solution