Suppress message from geom_line with only one point - r

Question

I'm iterating through multiple data sets to produce line plots for each set. How can I prevent ggplot from complaining when I use geom_line over one point?
Take, for example, the following data:
mydata = data.frame(
x = c(1, 2),
y = c(2, 2),
group = as.factor(c("foo", "foo"))
)
Creating line graph looks and works just fine because there are two points in the line:
ggplot(mydata, aes(x = x, y = y)) +
geom_point() +
geom_line(aes(group = group))
However, plotting only the fist row give the message:
geom_path: Each group consists of only one observation. Do you need to adjust the group aesthetic?
ggplot(mydata[1,], aes(x = x, y = y)) +
geom_point() +
geom_line(aes(group = group))
Some of my figures will only have one point and the messages cause hangups in the greater script that produces these figures. I know the plots still work, so my concern is avoiding the message. I'd also like to avoid using suppressWarnings() if possible in case another legitimate and unexpected issue arises.

Answer 1

Per an answer to this question: suppressMessages(ggplot()) fails because you have to wrap it around a print() call of the ggplot object--not the ggplot object itself. This is because the warning/message only occurs when the object is drawn.
So, to view your plot without a warning message run:
p <- ggplot(mydata[1,], aes(x = x, y = y)) +
geom_point() +
geom_line(aes(group = group))
suppressMessages(print(p))

Answer 2

I think the following if-else solution should resolve the problem:
if (nrow(mydata) > 1) {
ggplot(mydata, aes(x = x, y = y)) +
geom_point() +
geom_line(aes(group = group))
} else {
ggplot(mydata, aes(x = x, y = y)) +
geom_point()
}

Answer 3

On the community.RStudio.com, John Mackintosh suggests a solution which worked for me:
Freely quoting:
Rather than suppress warnings, change the plot layers slightly.
Facet wrap to create empty plot
Add geom_point for entire data frame
Subset the dataframe by creating a vector of groups with more than one data point, and filtering the original data for those groups. Only
plot lines for this subset.
Details and example code in the followup of the link above.