Fix plot unit tests

One unit test uses get_xlim(), which was removed earlier because it's
not used internally. get_ylim() no longer returns a list, so there's
no need to subset.

R/plot.R

@@ -929,6 +929,7 @@ new.replot_xts <- function(panel=1,asp=1,xlim=c(1,10),ylim=list(structure(c(1,10
   # getters
   get_panel <- function(n) { if (n == 0) get_last_action_panel() else Env$panels[[n]] }
   get_ylim  <- function() { update_panels(); get_active_panel()[["ylim_render"]] }
+  get_xlim  <- function() { update_panels(); Env$xlim }
   get_active_panel <- function() { get_panel(Env$active_panel_i) }
   get_last_action_panel <- function() { get_panel(Env$last_action_panel_id) }
 
@@ -1385,6 +1386,7 @@ new.replot_xts <- function(panel=1,asp=1,xlim=c(1,10),ylim=list(structure(c(1,10
   replot_env$update_panels <- update_panels
   replot_env$render_panels <- render_panels
   replot_env$get_panel <- get_panel
+  replot_env$get_xlim <- get_xlim
   replot_env$get_ylim <- get_ylim
   replot_env$create_ylim <- create_ylim
   replot_env$get_last_action_panel <- get_last_action_panel

inst/tinytest/test-plot.R

@@ -35,7 +35,7 @@ expect_equivalent(target, p$get_xlim(), info = info_msg)
 info_msg <- "test.ylim_set_before_rendering"
 x <- rnorm(10)
 p <- plot(xts(x, .Date(1:10)))
-expect_equivalent(range(x), p$get_ylim()[[2]], info = info_msg)
+expect_equivalent(range(x), p$get_ylim(), info = info_msg)
 
 info_msg <- "test.yaxis.ticks"
 x <- xts(rnorm(50), .Date(1:50))