On the latest daily desktop build (Version 1.2.730 Build 754 (e1a72523)) the code below fails with, Error in hist.default(hist_vals, plot = FALSE) : 'x' must be numeric.
Version 1.2.665 (for example) does not fail.
obs <- 1:10
d1 <- sample(seq(as.Date('2015-01-01'), as.Date('2016-01-01'), by="day"), 10)
d2 <- sample(seq(as.Date('2017-01-01'), as.Date('2018-01-01'), by="day"), 10)
delta <- difftime(d2, d1)
View(delta)
R version 3.5.0 (2018-04-23)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 7 x64 (build 7601) Service Pack 1