scale_shape_identity doesn't work with guide = 'legend'

[caayala]

Related to issue #402 and #2112, scale_shape_identity works with a continues variable but with the legend attribute, it doesn't.

library(ggplot2)

df2 <- data.frame(x = 1:5 , y = 1:10, z = 1:10)
s <- ggplot(df2, aes(x = x, y = y))
s + 
  geom_point(aes(shape = z), size = 4) + 
  scale_shape_identity(guide = 'legend')
#> Error: Continuous value supplied to discrete scale

^{Created on 2018-12-07 by the reprex package (v0.2.1)}

[clauswilke]

Looks like a typo in line 84:

ggplot2/R/scale-identity.r

Lines 82 to 84 in 4a607ca

	scale_shape_identity <- function(..., guide = "none") {
	sc <- continuous_scale("shape", "identity", identity_pal(), ..., guide = guide,
	super = ScaleDiscreteIdentity)

For a continuous scale, the last argument should be super = ScaleContinuousIdentity.

As a workaround, use scale_continuous_identity():

library(ggplot2)

df2 <- data.frame(x = 1:5 , y = 1:10, z = 1:10)
s <- ggplot(df2, aes(x = x, y = y))
s + 
  geom_point(aes(shape = z), size = 4) + 
  scale_continuous_identity(aesthetics = 'shape', guide = 'legend')

^{Created on 2018-12-07 by the reprex package (v0.2.1)}

[malcolmbarrett]

I'll work on this

[lock]

This old issue has been automatically locked. If you believe you have found a related problem, please file a new issue (with reprex) and link to this issue. https://reprex.tidyverse.org/