Update payload library + command-line tool

An initial implementation of a Python module for parsing, checking and
applying a Chrome OS update payload. Comes with a command-line tool
(paycheck.py) for applying such operations on payload files, and a test
script (test_paycheck.sh) for ensuring that the library and tool are
working correctly.

Since update_payload is introduced as a package, we're moving some
previously merged utilities into the package's directory.

(Unit testing for this code will be uploaded on a separate CL; see
chromium-os:39663)

BUG=chromium-os:34911,chromium-os:33607,chromium-os:7597
TEST=test_paycheck.sh successful on MP-signed payloads
CQ-DEPEND=I5746a1d80e822a575f0d96f94d0b4e765fc64507

Change-Id: I77123a1fffbb2059c239b7145c6922968fdffb6a
Reviewed-on: https://gerrit.chromium.org/gerrit/43041
Reviewed-by: Gilad Arnold <garnold@chromium.org>
Tested-by: Gilad Arnold <garnold@chromium.org>
Reviewed-by: Chris Sosa <sosa@chromium.org>
Reviewed-by: Jay Srinivasan <jaysri@chromium.org>
Reviewed-by: Don Garrett <dgarrett@chromium.org>
Commit-Queue: Gilad Arnold <garnold@chromium.org>

1 files changed, 60 insertions, 0 deletions

diff --git a/scripts/update_payload/histogram_unittest.py b/scripts/update_payload/histogram_unittest.py
new file mode 100755
index 00000000..421ff203
--- /dev/null
+++ b/scripts/update_payload/histogram_unittest.py
@@ -0,0 +1,60 @@
+#!/usr/bin/python
+#
+# Copyright (c) 2013 The Chromium OS Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Unit tests for histogram.py."""
+
+import unittest
+
+import format_utils
+import histogram
+
+
+class HistogramTest(unittest.TestCase):
+
+  @staticmethod
+  def AddHumanReadableSize(size):
+    fmt = format_utils.BytesToHumanReadable(size)
+    return '%s (%s)' % (size, fmt) if fmt else str(size)
+
+  def CompareToExpectedDefault(self, actual_str):
+    expected_str = (
+        'Yes |################    | 5 (83.3%)\n'
+        'No  |###                 | 1 (16.6%)'
+    )
+    self.assertEqual(actual_str, expected_str)
+
+  def testExampleHistogram(self):
+    self.CompareToExpectedDefault(str(histogram.Histogram(
+        [('Yes', 5), ('No', 1)])))
+
+  def testFromCountDict(self):
+    self.CompareToExpectedDefault(str(histogram.Histogram.FromCountDict(
+        {'Yes': 5, 'No': 1})))
+
+  def testFromKeyList(self):
+    self.CompareToExpectedDefault(str(histogram.Histogram.FromKeyList(
+        ['Yes', 'Yes', 'No', 'Yes', 'Yes', 'Yes'])))
+
+  def testCustomScale(self):
+    expected_str = (
+        'Yes |#### | 5 (83.3%)\n'
+        'No  |     | 1 (16.6%)'
+    )
+    actual_str = str(histogram.Histogram([('Yes', 5), ('No', 1)], scale=5))
+    self.assertEqual(actual_str, expected_str)
+
+  def testCustomFormatter(self):
+    expected_str = (
+        'Yes |################    | 5000 (4.8 KiB) (83.3%)\n'
+        'No  |###                 | 1000 (16.6%)'
+    )
+    actual_str = str(histogram.Histogram(
+        [('Yes', 5000), ('No', 1000)], formatter=self.AddHumanReadableSize))
+    self.assertEqual(actual_str, expected_str)
+
+
+if __name__ == '__main__':
+  unittest.main()