change in autoscale_view() behavior?

Hello,

I'm in the process of migrating some software I've written from a
machine with MPL 0.86.2 on it to another with 0.87.2 .

The app is Qt-based with MPL embedded as a widget. The plot itself uses
dates on the x-axis.

It appears that the behavior of autoscale_view() changed quite a bit
somewhere between these two versions.

In my application I create a patches.Rectangle that is 100 seconds wide:

    start_time_num = matplotlib.dates.date2num( start_time )
    lower_left = [ matplotlib.dates.date2num( start_time ), start_y ]
    width = matplotlib.dates.date2num( start_time + datetime.timedelta( seconds=10 ) ) - start_time_num
    r = matplotlib.patches.Rectangle( lower_left, width, height )

With the 0.86.2 version, the total span of the x-axis after an
autoscale_view() call is about 12 seconds. For the 0.87.2 version
however, the span is more than 200 years. (see attached .png files)

I don't see this type of behavior in the pylab environment, yet I'm
having a hard time creating a concise example that demonstrates the
behavior.

I can keep working on extracting an snippet, but I thought I'd ask
if this is some intended behavioral change, and if so, if there is a
workaround.

Thank you!
Glen Mabey

autoscale_view_0.86.2.png

autoscale_view_0.87.2.png