png.py 文件源码

def testWithIO(inp, out, f):
    """Calls the function `f` with ``sys.stdin`` changed to `inp`
    and ``sys.stdout`` changed to `out`.  They are restored when `f`
    returns.  This function returns whatever `f` returns.
    """

    import os

    try:
        oldin,sys.stdin = sys.stdin,inp
        oldout,sys.stdout = sys.stdout,out
        x = f()
    finally:
        sys.stdin = oldin
        sys.stdout = oldout
    if os.environ.get('PYPNG_TEST_TMP') and hasattr(out,'getvalue'):
        name = mycallersname()
        if name:
            w = open(name+'.png', 'wb')
            w.write(out.getvalue())
            w.close()
    return x