How to make a density plot in ggplot2 with dates on the x-axis

Question

I have a dataframe df with a column time which contains R date objects and I want to plot a density plot to see which days had the most activity. I don't want to convert to timestamps, because I would prefer more meaningful labels in the x-axis.

My attempt

Here is what I am trying:

ggplot(df, aes(x = time)) + geom_density(stat="identity") + scale_x_date()

which gives the error

Error in as.environment(where) : 'where' is missing

Here is the output of dput(df) :

structure(list(time = structure(c(15863, 15887, 15865, 15873, 15885, 15878), class = "Date")), .Names = "time", row.names = 8831395:8831400, class = "data.frame")

Answer 1

For some reason the argument to stat_density is causing ggplot to lose its way among the environments that get set up. (At least that's where the "where" missing error comes from.) This succeeds:

 ggplot(df, aes(x = time)) + geom_density()