add fixes and unit tests

Author: 13bzhang

R/ggplotly.R

@@ -629,8 +629,10 @@ gg2list <- function(p) {
     layout$margin$r <- 60
   }
   layout$legend <- list(bordercolor = "transparent", 
-                        x = 1.01, y = 0.5,
-                        xanchor = "left", yanchor = "center")
+                        x = 1.01, 
+                        y = 0.075 * 0.5* length(trace.list) + 0.45,
+                        xref="paper", yref="paper",
+                        xanchor = "left", yanchor = "top")
 
   ## Legend hiding when guides(fill="none").
   legends.present <- unique(unlist(layer.legends))
@@ -675,16 +677,14 @@ gg2list <- function(p) {
       nann <- 1
     }
     annotations[[nann]] <- list(text=legend.title,
-                                x= layout$legend$x * 1.0154,
-                                y= layout$legend$y + 
-                                  0.5 * length(trace.list) * 0.10,
+                                x = layout$legend$x * 1.0154,
+                                y = 0.075 * 0.5* length(trace.list) + 0.55,
                                 showarrow=FALSE,
                                 xref="paper", yref="paper",
-                                xanchor="left", yanchor = "center",
+                                xanchor="left", yanchor = "top",
                                 textangle=0)
     layout$annotations <- annotations
   }
-  
   # Family font for text
   if (!is.null(theme.pars$text$family)) {
     layout$titlefont$family   <- theme.pars$text$family

tests/testthat/test-ggplot-legend.R

@@ -84,3 +84,37 @@ test_that("0 breaks -> 3 traces with showlegend=FALSE", {
   computed.showlegend <- sapply(info$traces, "[[", "showlegend")
   expect_identical(as.logical(computed.showlegend), expected.showlegend)
 })
+
+# test of legend position
+test_that("very long legend items", {
+  long_items <- data.frame(cat1 = sample(x = LETTERS[1:10], 
+                                         size = 100, replace = TRUE),
+                           cat2 = sample(x = c("AAAAAAAAAAAAAAAAAAAAAAAAAAAAA",
+                                               "BBBBBBBBBBBBBBBBBBBBBBBBBBBBB",
+                                               "CCCCCCCCCCCCCCCCCCCCCCCCCCCCC"),
+                                         size = 100, replace = TRUE))
+  p_long_items <- ggplot(long_items, aes(cat1, fill=cat2)) + 
+    geom_bar(position="dodge")
+  info <- expect_traces(p_long_items, 3, "very long legend items")
+  expect_equal(length(info$layout$annotations), 1)
+  expected.names <- levels(long_items$cat2)
+  expect_identical(info$layout$annotations[[1]]$y - 
+                     info$layout$legend$y > 0, TRUE)
+})
+
+# test of legend position
+test_that("many legend items", {
+  many_items <- data.frame(cat1 = sample(x = paste0("Group ", LETTERS[1:12]), 
+                                         size = 100, replace = TRUE),
+                           cat2 = sample(x = c("foo", "bar", "baz"),
+                                         size = 100, replace = TRUE))
+  p_many_items <- ggplot(many_items, aes(cat2, fill=cat1)) + 
+    geom_bar(position="dodge")
+  info <- expect_traces(p_long_items, 3, "many legend items")
+  expect_equal(length(info$layout$annotations), 1)
+  expected.names <- levels(long_items$cat2)
+  expect_identical(info$layout$annotations[[1]]$y > 0.5, TRUE)
+  expect_identical(info$layout$annotations[[1]]$y - 
+                     info$layout$legend$y > 0, TRUE)
+})
+