add some tests

Author: cpsievert

tests/testthat/test-ggplot-facets.R

@@ -7,6 +7,14 @@ test_that("6 facets becomes 6 panels", {
     theme_bw() +
     theme(panel.margin = grid::unit(0, "cm"))
   info <- save_outputs(gg, "barley")
+  # two legend entries, but two groups
+  expect_equal(sum(sapply(l$data, "[[", "showlegend")), 2)
+  expect_identical(
+    sort(unique(sapply(l$data, "[[", "legendgroup"))), c("1931", "1932")
+  )
+  expect_identical(
+    sort(unique(sapply(l$data, "[[", "name"))), c("1931", "1932")
+  )
 })
 
 test_that("3 facets becomes 3 panels", {