Time, a time-conversion library for gas-include

$ npm i -g google-apps-script
$ gas new myProject && cd myProject
$ gas i -s time
$ gas push

Usage

Number of complete days between two dates

time_dayDiff(StartDate, EndDate);

Number of complete hours between two dates

time_hourDiff(StartDate, EndDate);

Number of complete minutes between two dates

time_minuteDiff(StartDate, EndDate);

Number of complete seconds between two dates

time_secondDiff(StartDate, EndDate);