Add ByteSpeed.

3 files changed, 116 insertions, 0 deletions

diff --git a/ttystatus/__init__.py b/ttystatus/__init__.py
index d3b473b..64c1a6a 100644
--- a/ttystatus/__init__.py
+++ b/ttystatus/__init__.py
@@ -30,3 +30,4 @@ from percent import PercentDone
 from progressbar import ProgressBar
 from remtime import RemainingTime
 from elapsed import ElapsedTime
+from bytespeed import ByteSpeed
diff --git a/ttystatus/bytespeed.py b/ttystatus/bytespeed.py
new file mode 100644
index 0000000..7f54b86
--- /dev/null
+++ b/ttystatus/bytespeed.py
@@ -0,0 +1,61 @@
+# Copyright 2010  Lars Wirzenius
+# 
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+# 
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+import time
+
+import ttystatus
+
+
+class ByteSpeed(ttystatus.Widget):
+
+    '''Display data size in bytes, KiB, etc.'''
+    
+    def __init__(self, name):
+        self.name = name
+        self.interesting_keys = [name]
+        self._bytes = 0
+        self._started = None
+        
+    def now(self):
+        '''Wrapper around time.time for unit tests to overrride.'''
+        
+        return time.time()
+        
+    def format(self):
+        units = (
+            (1024**4, 2, 'TiB/s'),
+            (1024**3, 2, 'GiB/s'),
+            (1024**2, 2, 'MiB/s'),
+            (1024**1, 1, 'KiB/s'),
+        )
+        
+        if self._started is None:
+            return '0 B/s'
+        
+        duration = self.now() - self._started
+        speed = self._bytes / duration
+        
+        for factor, decimals, unit in units:
+            if speed >= factor:
+                return '%.*f %s' % (decimals,
+                                    float(speed) / float(factor), 
+                                    unit)
+        return '%.0f B/s' % speed
+        
+    def update(self, master, width):
+        if self._started is None:
+            self._started = self.now()
+        self._bytes = master[self.name]
diff --git a/ttystatus/bytespeed_tests.py b/ttystatus/bytespeed_tests.py
new file mode 100644
index 0000000..4c481fe
--- /dev/null
+++ b/ttystatus/bytespeed_tests.py
@@ -0,0 +1,54 @@
+# Copyright 2010  Lars Wirzenius
+# 
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+# 
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+import unittest
+
+import ttystatus
+
+
+class ByteSpeedTests(unittest.TestCase):
+
+    def setUp(self):
+        self.w = ttystatus.ByteSpeed('foo')
+
+    def test_formats_zero_speed_without_update(self):
+        self.assertEqual(str(self.w), '0 B/s')
+
+    def test_formats_zero_bytes_correctly(self):
+        self.w.update({ 'foo': 0 }, 999)
+        self.assertEqual(str(self.w), '0 B/s')
+
+    def test_formats_one_byte_per_second_correctly(self):
+        self.w.now = lambda: 1
+        self.w.update({ 'foo': 0 }, 999)
+        self.w.now = lambda: 2
+        self.w.update({ 'foo': 1 }, 999)
+        self.assertEqual(str(self.w), '1 B/s')
+
+    def test_formats_ten_bytes_per_second_correctly(self):
+        self.w.now = lambda: 1
+        self.w.update({ 'foo': 0 }, 999)
+        self.w.now = lambda: 11
+        self.w.update({ 'foo': 100 }, 999)
+        self.assertEqual(str(self.w), '10 B/s')
+
+    def test_formats_ten_tibs_per_second_correctly(self):
+        self.w.now = lambda: 1
+        self.w.update({ 'foo': 0 }, 999)
+        self.w.now = lambda: 2
+        self.w.update({ 'foo': 10 * 1024**4 }, 999)
+        self.assertEqual(str(self.w), '10.00 TiB/s')
+