[BUG] DatePicker display off-by-one in non-GMT timezone after upgrade to 1.4.0 #9494
Description
Versions:
- Bokeh: 1.4.0
- Python: 3.7.3
- Chrome: 78.0.3904.108 (Official Build) (64-bit)
- O/S: Windows 7 Pro SP1
- TimeZone: EST (Issue observed in EST but not in GMT)
After the fix of this issue in 1.4, I observe the following issue;
In the EST timezone, if I up 71A0 date a DatePicker based on the value of another DatePicker, I get a different date (1 day previous to the selected date). If the browser is located in a GMT timezone then I do not observe the issue. Minimal example below.
Expected behavior: On selecting a date from the first DatePicker, the second DatePicker displays that same date;
Observed behavior: On selecting a date from the first DatePicker, the second DatePicker shows a date one day previous to the selected date;
from bokeh.layouts import column
from bokeh.models import DatePicker
from bokeh.plotting import curdoc
def a_changed(attr, old, new):
date_picker_b.value = new
date_picker_a = DatePicker()
date_picker_b = DatePicker()
# When we pick a date in date_picker_a, set the date in date_picker_b
date_picker_a.on_change('value', a_changed)
curdoc().add_root(column(date_picker_a, date_picker_b))
In our application, we have a date slider and some fixed date-range buttons (year-to-date, month-to-date etc) coupled to two date pickers, which is how we observed the issue, but the above example seems to minimally demonstrate the issue that dates don't round-trip from the DatePickers.