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

class TestTask(unittest.TestCase):
    def test_prints_only_lines_with_keyword(self):
        import user_code
        importlib.reload(user_code)
        lines = [
            "Error: File not found",
            "Warning: Low disk space",
            "Info: Update completed",
            "Error: Access denied"
        ]
        keyword = "Error"
        f = io.StringIO()
        with redirect_stdout(f):
            user_code.print_lines_with_keyword(lines, keyword)
        output = normalize_text(f.getvalue())
        expected_lines = ["Error: File not found", "Error: Access denied"]
        for expected in expected_lines:
            _dynamic_test(
                self,
                normalize_text(expected) in output,
                f"Output includes line: {expected}",
                f"Expected output: '{expected}' not found in: '{output}'",
            )
        # Ensure no unwanted lines are printed
        not_expected = ["Warning: Low disk space", "Info: Update completed"]
        for line in not_expected:
            _dynamic_test(
                self,
                normalize_text(line) not in output,
                f"Output does not include line: {line}",
                f"Unexpected output: '{line}' found in: '{output}'",
            )

    def test_prints_nothing_if_no_match(self):
        import user_code
        importlib.reload(user_code)
        lines = ["alpha", "bravo", "charlie"]
        keyword = "zulu"
        f = io.StringIO()
        with redirect_stdout(f):
            user_code.print_lines_with_keyword(lines, keyword)
        output = normalize_text(f.getvalue())
        _dynamic_test(
            self,
            output.strip() == "",
            "No output printed when there are no matches",
            f"Expected no output, but got: {output}",
        )

    def test_keyword_at_various_positions(self):
        import user_code
        importlib.reload(user_code)
        lines = [
            "apple pie",           # keyword at start
            "I like apple juice", # keyword in middle
            "juice with apple"    # keyword at end
        ]
        keyword = "apple"
        f = io.StringIO()
        with redirect_stdout(f):
            user_code.print_lines_with_keyword(lines, keyword)
        output = normalize_text(f.getvalue())
        for expected in lines:
            _dynamic_test(
                self,
                normalize_text(expected) in output,
                f"Output includes line: {expected}",
                f"Expected output: '{expected}' not found in: '{output}'",
            )

    def test_prints_multiple_matches(self):
        import user_code
        importlib.reload(user_code)
        lines = [
            "apple pie",
            "banana bread",
            "apple turnover",
            "grape jelly"
        ]
        keyword = "apple"
        f = io.StringIO()
        with redirect_stdout(f):
            user_code.print_lines_with_keyword(lines, keyword)
        output = normalize_text(f.getvalue())
        expected = ["apple pie", "apple turnover"]
        for line in expected:
            _dynamic_test(
                self,
                normalize_text(line) in output,
                f"Output includes line: {line}",
                f"Expected output: '{line}' not found in: '{output}'",
            )
        not_expected = ["banana bread", "grape jelly"]
        for line in not_expected:
            _dynamic_test(
                self,
                normalize_text(line) not in output,
                f"Output does not include line: {line}",
                f"Unexpected output: '{line}' found in: '{output}'",
            )

    def test_empty_lines_list(self):
        import user_code
        importlib.reload(user_code)
        lines = []
        keyword = "anything"
        f = io.StringIO()
        with redirect_stdout(f):
            user_code.print_lines_with_keyword(lines, keyword)
        output = normalize_text(f.getvalue())
        _dynamic_test(
            self,
            output.strip() == "",
            "No output printed when lines list is empty",
            f"Expected no output, but got: {output}",
        )

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: Find Lines with Keyword

Solution