Error from facet_wrap(strip.position = "bottom") + theme_void()

[heavywatal]

• OK: facet_wrap(~cyl, ncol = 2L, strip.position = "bottom") + theme_grey()
• NG: facet_wrap(~cyl, ncol = 2L, strip.position = "bottom") + theme_void()
• OK: facet_wrap(~cyl, ncol = 2L, strip.position = "left") + theme_void()
• OK: facet_wrap(~cyl, ncol = NULL, strip.position = "bottom") + theme_void()

It is observed with both release 3.1.0 and master

ggplot(mtcars, aes(disp, mpg)) +
  geom_point() +
  facet_wrap(~cyl, ncol = 2L, strip.position = "bottom") +
  theme_void()
# Error in if (params$strip.position == "bottom" && theme$strip.placement !=  :
#   missing value where TRUE/FALSE needed
# Calls: <Anonymous> ... ggplot_gtable.ggplot_built -> <Anonymous> -> f -> <Anonymous> -> f

[yutannihilation]

The error occurs here because theme$strip.placement is NULL.

ggplot2/R/facet-wrap.r

Lines 298 to 305 in 7f13dfa

	if (params$strip.position == "bottom" &&
	theme$strip.placement != "inside" &&
	any(!vapply(row_axes, is.zero, logical(1))) &&
	!params$free$x) {
	warning("Suppressing axis rendering when strip.position = 'bottom' and strip.placement == 'outside'", call. = FALSE)
	} else {
	axis_mat_x_bottom[row_pos] <- row_axes
	}

I think this == and != should be replaced with identical() or wrapped with isTRUE() for safety. But, potentially, this can be counted as one of theme_void()'s problems. c.f. #3039 (comment).

[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/