1from __future__ import absolute_import
2
3# System modules
4import time
5
6# Third-party modules
7
8# LLDB modules
9from .lldbtest import *
10
11class Stopwatch(object):
12    """Stopwatch provides a simple utility to start/stop your stopwatch multiple
13    times.  Each start/stop is equal to a lap, with its elapsed time accumulated
14    while measurment is in progress.
15
16    When you're ready to start from scratch for another round of measurements,
17    be sure to call the reset() method.
18
19    For example,
20
21    sw = Stopwatch()
22    for i in range(1000):
23        with sw:
24            # Do some length operations...
25            ...
26    # Get the average time.
27    avg_time = sw.avg()
28
29    # Reset the stopwatch as we are about to perform other kind of operations.
30    sw.reset()
31    ...
32    """
33
34    #############################################################
35    #
36    # Context manager interfaces to support the 'with' statement.
37    #
38    #############################################################
39
40    def __enter__(self):
41        """
42        Context management protocol on entry to the body of the with statement.
43        """
44        return self.start()
45
46    def __exit__(self, type, value, tb):
47        """
48        Context management protocol on exit from the body of the with statement.
49        """
50        self.stop()
51
52    def reset(self):
53        self.__laps__ = 0
54        self.__total_elapsed__ = 0.0
55        self.__start__ = None
56        self.__stop__ = None
57        self.__elapsed__ = 0.0
58        self.__nums__ = []
59
60    def __init__(self):
61        self.reset()
62
63    def start(self):
64        if self.__start__ is None:
65            self.__start__ = time.time()
66        else:
67            raise Exception("start() already called, did you forget to stop() first?")
68        # Return self to facilitate the context manager __enter__ protocol.
69        return self
70
71    def stop(self):
72        if self.__start__ is not None:
73            self.__stop__ = time.time()
74            elapsed = self.__stop__ - self.__start__
75            self.__total_elapsed__ += elapsed
76            self.__laps__ += 1
77            self.__nums__.append(elapsed)
78            self.__start__ = None # Reset __start__ to be None again.
79        else:
80            raise Exception("stop() called without first start()?")
81
82    def laps(self):
83        """Gets the number of laps. One lap is equal to a start/stop action."""
84        return self.__laps__
85
86    def avg(self):
87        """Equal to total elapsed time divided by the number of laps."""
88        return self.__total_elapsed__ / self.__laps__
89
90    #def sigma(self):
91    #    """Return the standard deviation of the available samples."""
92    #    if self.__laps__ <= 0:
93    #        return None
94    #    return numpy.std(self.__nums__)
95
96    def __str__(self):
97        return "Avg: %f (Laps: %d, Total Elapsed Time: %f, min=%f, max=%f)" % (self.avg(),
98                                                                               self.__laps__,
99                                                                               self.__total_elapsed__,
100                                                                               min(self.__nums__),
101                                                                               max(self.__nums__))
102
103class BenchBase(TestBase):
104    """
105    Abstract base class for benchmark tests.
106    """
107    def setUp(self):
108        """Fixture for unittest test case setup."""
109        super(BenchBase, self).setUp()
110        #TestBase.setUp(self)
111        self.stopwatch = Stopwatch()
112
113    def tearDown(self):
114        """Fixture for unittest test case teardown."""
115        super(BenchBase, self).tearDown()
116        #TestBase.tearDown(self)
117        del self.stopwatch
118
119