Add a bar that shows a label in the center.

Include a specialization with a percentage in the center.

Author: Zannick

progressbar/__init__.py

@@ -26,6 +26,8 @@
     VariableMixin,
     MultiRangeBar,
     MultiProgressBar,
+    FormatLabelBar,
+    PercentageLabelBar,
     Variable,
     DynamicMessage,
     FormatCustomText,
@@ -72,6 +74,8 @@
     'VariableMixin',
     'MultiRangeBar',
     'MultiProgressBar',
+    'FormatLabelBar',
+    'PercentageLabelBar',
     'Variable',
     'DynamicMessage',
     'FormatCustomText',

progressbar/widgets.py

@@ -909,6 +909,37 @@ def get_values(self, progress, data):
         return ranges
 
 
+class FormatLabelBar(FormatLabel, Bar):
+    '''A bar which has a formatted label in the center.'''
+    def __init__(self, format, **kwargs):
+        FormatLabel.__init__(self, format, **kwargs)
+        Bar.__init__(self, **kwargs)
+
+    def __call__(self, progress, data, width, format=None):
+        center = FormatLabel.__call__(self, progress, data, format=format)
+        bar = Bar.__call__(self, progress, data, width)
+
+        # Aligns the center of the label to the center of the bar
+        center_len = progress.custom_len(center)
+        center_left = int((width - center_len) / 2)
+        center_right = center_left + center_len
+        return bar[:center_left] + center + bar[center_right:]
+
+
+class PercentageLabelBar(Percentage, FormatLabelBar):
+    '''A bar which displays the current percentage in the center.'''
+    # %3d adds an extra space that makes it look off-center
+    # %2d keeps the label somewhat consistently in-place
+    def __init__(self, format='%(percentage)2d%%', na='N/A%%', **kwargs):
+        Percentage.__init__(self, format, na=na, **kwargs)
+        FormatLabelBar.__init__(self, format, **kwargs)
+
+    def __call__(self, progress, data, width, format=None):
+        return FormatLabelBar.__call__(
+            self, progress, data, width,
+            format=Percentage.get_format(self, progress, data, format=None))
+
+
 class Variable(FormatWidgetMixin, VariableMixin, WidgetBase):
     '''Displays a custom variable.'''
 

tests/test_monitor_progress.py

@@ -186,6 +186,26 @@ def test_no_line_breaks(testdir):
     ]
 
 
+def test_percentage_label_bar(testdir):
+    result = testdir.runpython(testdir.makepyfile(_create_script(
+        widgets='[progressbar.PercentageLabelBar()]',
+        line_breaks=False,
+        items=list(range(5)),
+    )))
+    pprint.pprint(result.stderr.lines, width=70)
+    assert result.stderr.lines == [
+        u'',
+        u'|                            0%                            |',
+        u'|###########                20%                            |',
+        u'|#######################    40%                            |',
+        u'|###########################60%####                        |',
+        u'|###########################80%################            |',
+        u'|###########################100%###########################|',
+        u'',
+        u'|###########################100%###########################|'
+    ]
+
+
 def test_colors(testdir):
     kwargs = dict(
         items=range(1),