nilmdb/tests/test_timestamper.py

import nilmdb
from nilmdb.utils.printf import *

import datetime_tz

from nose.tools import *
from nose.tools import assert_raises
import os
import sys
import cStringIO

from testutil.helpers import *

from nilmdb.utils import timestamper

class TestTimestamper(object):

    # Not a very comprehensive test, but it's good enough.

    def test_timestamper(self):
        def join(list):
            return "\n".join(list) + "\n"

        start = datetime_tz.datetime_tz.smartparse("03/24/2012").totimestamp()
        lines_in  = [ "hello", "world", "hello world", "# commented out" ]
        lines_out = [ "1332561600.000000 hello",
                      "1332561600.000125 world",
                      "1332561600.000250 hello world" ]

        # full
        input = cStringIO.StringIO(join(lines_in))
        ts = timestamper.TimestamperRate(input, start, 8000)
        foo = ts.readlines()
        eq_(foo, join(lines_out))
        in_("TimestamperRate(..., start=", str(ts))

        # first 30 or so bytes means the first 2 lines
        input = cStringIO.StringIO(join(lines_in))
        ts = timestamper.TimestamperRate(input, start, 8000)
        foo = ts.readlines(30)
        eq_(foo, join(lines_out[0:2]))

        # stop iteration early
        input = cStringIO.StringIO(join(lines_in))
        ts = timestamper.TimestamperRate(input, start, 8000,
                                                1332561600.000200)
        foo = ""
        for line in ts:
            foo += line
        eq_(foo, join(lines_out[0:2]))

        # stop iteration early (readlines)
        input = cStringIO.StringIO(join(lines_in))
        ts = timestamper.TimestamperRate(input, start, 8000,
                                                1332561600.000200)
        foo = ts.readlines()
        eq_(foo, join(lines_out[0:2]))

        # stop iteration really early
        input = cStringIO.StringIO(join(lines_in))
        ts = timestamper.TimestamperRate(input, start, 8000,
                                                1332561600.000000)
        foo = ts.readlines()
        eq_(foo, "")

        # use iterator
        input = cStringIO.StringIO(join(lines_in))
        ts = timestamper.TimestamperRate(input, start, 8000)
        foo = ""
        for line in ts:
            foo += line
        eq_(foo, join(lines_out))

        # check that TimestamperNow gives similar result
        input = cStringIO.StringIO(join(lines_in))
        ts = timestamper.TimestamperNow(input)
        foo = ts.readlines()
        ne_(foo, join(lines_out))
        eq_(len(foo), len(join(lines_out)))
        eq_(str(ts), "TimestamperNow(...)")

        # Test passing a file (should be empty)
        ts = timestamper.TimestamperNow("/dev/null")
        for line in ts:
            raise AssertionError
        ts.close()

        # Test the null timestamper
        input = cStringIO.StringIO(join(lines_out))  # note: lines_out
        ts = timestamper.TimestamperNull(input)
        foo = ts.readlines()
        eq_(foo, join(lines_out))
        eq_(str(ts), "TimestamperNull(...)")