[core/output] Add widget drawing

Add basic drawing of widgets. Each module instance returns a list of
widgets using the widgets() method which is then forwarded to the draw()
method of the configured output.

see #23

bumblebee/engine.py

@@ -48,7 +48,10 @@ class Engine(object):
         """Start the event loop"""
         self._output.start()
         while self.running():
-            pass
+            widgets = []
+            for module in self._modules:
+                widgets += module.widgets()
+            self._output.draw(widgets)
 
         self._output.stop()
 

bumblebee/output.py

@@ -18,4 +18,15 @@ class I3BarOutput(object):
         """Finish i3bar protocol"""
         sys.stdout.write("]\n")
 
+    def draw(self, widgets):
+        """Draw a number of widgets"""
+        if not isinstance(widgets, list):
+            widgets = [widgets]
+        result = []
+        for widget in widgets:
+            result.append({
+                u"full_text": widget.text()
+            })
+        sys.stdout.write(json.dumps(result))
+
 # vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4

tests/test_i3baroutput.py

@@ -1,4 +1,5 @@
 # pylint: disable=C0103,C0111
+
 import json
 import unittest
 import mock
@@ -8,12 +9,14 @@ except ImportError:
     from io import StringIO
 
 from bumblebee.output import I3BarOutput
+from tests.util import MockWidget
 
 class TestI3BarOutput(unittest.TestCase):
     def setUp(self):
         self.output = I3BarOutput()
         self.expectedStart = json.dumps({"version": 1, "click_events": True}) + "[\n"
         self.expectedStop = "]\n"
+        self.someWidget = MockWidget("foo bar baz")
 
     @mock.patch("sys.stdout", new_callable=StringIO)
     def test_start(self, stdout):
@@ -25,4 +28,17 @@ class TestI3BarOutput(unittest.TestCase):
         self.output.stop()
         self.assertEquals(self.expectedStop, stdout.getvalue())
 
+    @mock.patch("sys.stdout", new_callable=StringIO)
+    def test_draw_single_widget(self, stdout):
+        self.output.draw(self.someWidget)
+        result = json.loads(stdout.getvalue())[0]
+        self.assertEquals(result["full_text"], self.someWidget.text())
+
+    @mock.patch("sys.stdout", new_callable=StringIO)
+    def test_draw_multiple_widgets(self, stdout):
+        self.output.draw([self.someWidget, self.someWidget])
+        result = json.loads(stdout.getvalue())
+        for res in result:
+            self.assertEquals(res["full_text"], self.someWidget.text())
+
 # vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4

tests/util.py

@@ -0,0 +1,10 @@
+# pylint: disable=C0103,C0111
+
+class MockWidget(object):
+    def __init__(self, text):
+        self._text = text
+
+    def text(self):
+        return self._text
+
+# vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4