#!/usr/bin/python

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"""Package that private an array-based implementation of a stream."""

class ArrayStream(object):

    """Simple class that implmements a stream interface on top of an array.

    This is used primarily by unit test classes to mock output streams. It

    performs a similar function to StringIO, but (a) it is write-only, and

    (b) it can be used to retrieve each individual write(); StringIO 

    concatenates all of the writes together.

    """

    def __init__(self):

        self._contents = []

    def write(self, msg):

        """Implement stream.write() by appending to the stream's contents."""

        self._contents.append(msg)

    def get(self):

        """Return the contents of a stream (as an array)."""

        return self._contents

    def reset(self):

        """Empty the stream."""

        self._contents = []

    def empty(self):

        """Return whether the stream is empty."""

        return (len(self._contents) == 0)

    def flush(self):

        """Flush the stream (a no-op implemented for compatibility)."""

        pass

    def __repr__(self):

        return '<ArrayStream: ' + str(self._contents) + '>'