InfoPath Dev

 There is a way in a SharePoint list to use a calculated column to calculate the week ending date (based on a Sunday through Saturday week) using any date in that week.    This is the formula you would use in the calculated column.   Because it uses the weekday function I am not sure how to change it to use in InfoPath.

 =TEXT([Selected Date]+(7-WEEKDAY([Selected Date])),"mm/dd/yyyy")  "Selected Date" being the name of the column that contains the date for the calculation.

 How would I do this in InfoPath?

 I don't know of a similar option in InfoPath - probably a way with qRules, or someone may have come up with complicated rule variation - https://aemadhavan.wordpress.com/2013/07/24/calculating-day-of-the-week-in-infopath-without-code/ might be a starting point....