Python 2 fixes for progress bar implementation.

2 files changed, 10 insertions, 3 deletions

diff --git a/prompt_toolkit/shortcuts/progress_bar/base.py b/prompt_toolkit/shortcuts/progress_bar/base.py
index b111396d..8e35c30d 100644
--- a/prompt_toolkit/shortcuts/progress_bar/base.py
+++ b/prompt_toolkit/shortcuts/progress_bar/base.py
@@ -128,7 +128,9 @@ class progress_bar(object):
             return formatter.get_width(progress_bar=self)
 
         progress_controls = [
-            Window(content=_ProgressControl(self, f), width=functools.partial(width_for_formatter, f))
+            Window(
+                content=_ProgressControl(self, f),
+                width=functools.partial(width_for_formatter, f))
             for f in self.formatters
         ]
 
@@ -289,7 +291,7 @@ class ProgressBarCounter(object):
         """
         Timedelta representing the time left.
         """
-        if self.total is None:
+        if self.total is None or not self.percentage:
             return None
         else:
             return self.time_elapsed * (100 - self.percentage) / self.percentage
diff --git a/prompt_toolkit/utils.py b/prompt_toolkit/utils.py
index f1cc66fa..062fc7b1 100644
--- a/prompt_toolkit/utils.py
+++ b/prompt_toolkit/utils.py
@@ -6,6 +6,7 @@ import sys
 import threading
 import weakref
 
+from functools import partial
 from six import PY2
 from six.moves import range
 from wcwidth import wcwidth
@@ -121,7 +122,11 @@ def test_callable_args(func, args):
         else:
             return True
     else:
-        # For older Python versions, fall back to using getargspec.
+        # For older Python versions, fall back to using getargspec
+        # and don't check for `partial`.
+        if isinstance(func, partial):
+            return True
+
         spec = inspect.getargspec(func)
 
         # Drop the 'self'