This method is deprecated or moved on the latest stable version.
The last existing version (v3.2.13) is shown here.
beginning_of_week(start_day = :monday)
public
Returns a new Date/DateTime representing
the start of this week. Week is assumed to start on start_day,
default is :monday. DateTime objects have their time set to
0:00.
# File activesupport/lib/active_support/core_ext/date/calculations.rb, line 188
def beginning_of_week(start_day = :monday)
days_to_start = days_to_week_start(start_day)
result = self - days_to_start
acts_like?(:time) ? result.midnight : result
end