example_revert

class MemoryLogHandler(logging.Handler):
    def __init__(self):
        super().__init__()
        self.records = []

    def emit(self, record):
        self.records.append(self.format(record))

    def filter_lines(self, pattern: str) -> list[str]:
        """Return logs that match the pattern regex."""
        return [line for line in self.records if pattern in line]