| # Copyright 2013 The Chromium Authors. All rights reserved. |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| |
| import json |
| import unittest |
| |
| from metrics import histogram_util |
| |
| class TestHistogram(unittest.TestCase): |
| def testSubtractHistogram(self): |
| baseline_histogram = """{"count": 3, "buckets": [ |
| {"low": 1, "high": 2, "count": 1}, |
| {"low": 2, "high": 3, "count": 2}]}""" |
| |
| later_histogram = """{"count": 14, "buckets": [ |
| {"low": 1, "high": 2, "count": 1}, |
| {"low": 2, "high": 3, "count": 3}, |
| {"low": 3, "high": 4, "count": 10}]}""" |
| |
| new_histogram = json.loads( |
| histogram_util.SubtractHistogram(later_histogram, baseline_histogram)) |
| new_buckets = dict() |
| for b in new_histogram['buckets']: |
| new_buckets[b['low']] = b['count'] |
| self.assertFalse(1 in new_buckets) |
| self.assertEquals(1, new_buckets[2]) |
| self.assertEquals(10, new_buckets[3]) |
