declare trans as function rather than strings

tests/testthat/test-guides.R

@@ -346,7 +346,7 @@ test_that("guide_colourbar warns about discrete scales", {
 
 test_that("guide_axis_logticks calculates appropriate ticks", {
 
-  test_scale <- function(trans = "identity", limits = c(NA, NA)) {
+  test_scale <- function(trans = identity_trans(), limits = c(NA, NA)) {
     scale <- scale_x_continuous(trans = trans)
     scale$train(scale$transform(limits))
     view_scale_primary(scale)
@@ -362,28 +362,28 @@ test_that("guide_axis_logticks calculates appropriate ticks", {
   outcome <- c((1:10)*10, (2:10)*100)
 
   # Test the classic log10 transformation
-  scale <- test_scale("log10", c(10, 1000))
+  scale <- test_scale(log10_trans(), c(10, 1000))
   key <- train_guide(guide, scale)$logkey
 
   expect_equal(sort(key$x), log10(outcome))
   expect_equal(key$.type, rep(c(1,2,3), c(3, 2, 14)))
 
   # Test compound transformation
-  scale <- test_scale(c("log10", "reverse"), c(10, 1000))
+  scale <- test_scale(compose_trans(log10_trans(), reverse_trans()), c(10, 1000))
   key   <- train_guide(guide, scale)$logkey
 
   expect_equal(sort(key$x), -log10(rev(outcome)))
 
   # Test transformation with negatives
-  scale <- test_scale("pseudo_log", c(-1000, 1000))
+  scale <- test_scale(pseudo_log_trans(), c(-1000, 1000))
   key   <- train_guide(guide, scale)$logkey
 
   unlog <- sort(pseudo_log_trans()$inverse(key$x))
   expect_equal(unlog, c(-rev(outcome), 0, outcome))
   expect_equal(key$.type, rep(c(1,2,3), c(7, 4, 28)))
 
   # Test expanded argument
-  scale <- test_scale("log10", c(20, 900))
+  scale <- test_scale(log10_trans(), c(20, 900))
   scale$continuous_range <- c(1, 3)
 
   guide <- guide_axis_logticks(expanded = TRUE)
@@ -404,7 +404,7 @@ test_that("guide_axis_logticks calculates appropriate ticks", {
   expect_equal(sort(key$x), log2(outcome))
 
   # Should warn when scale also has transformation
-  scale <- test_scale("log10", limits = c(10, 1000))
+  scale <- test_scale(log10_trans(), limits = c(10, 1000))
   expect_snapshot_warning(train_guide(guide, scale)$logkey)
 
 })
@@ -618,12 +618,12 @@ test_that("logticks look as they should", {
 
   p <- ggplot(data.frame(x = c(-100, 100), y = c(10, 1000)), aes(x, y)) +
     geom_point() +
-    scale_y_continuous(trans = c("log10", "reverse"),
+    scale_y_continuous(trans = compose_trans(log10_trans(), reverse_trans()),
                        expand = expansion(add = 0.5)) +
     scale_x_continuous(
       breaks = c(-100, -10, -1, 0, 1, 10, 100)
     ) +
-    coord_trans(x = "pseudo_log") +
+    coord_trans(x = pseudo_log_trans()) +
     theme_test() +
     theme(axis.line = element_line(colour = "black"),
           panel.border = element_blank(),