fix nudging with multiple values. closes #2977 (#3024)

Author: clauswilke

R/position-nudge.R

@@ -47,13 +47,13 @@ PositionNudge <- ggproto("PositionNudge", Position,
 
   compute_layer = function(data, params, panel) {
     # transform only the dimensions for which non-zero nudging is requested
-    if (params$x != 0) {
-      if (params$y != 0) {
+    if (any(params$x != 0)) {
+      if (any(params$y != 0)) {
         transform_position(data, function(x) x + params$x, function(y) y + params$y)
       } else {
         transform_position(data, function(x) x + params$x, NULL)
       }
-    } else if (params$y != 0) {
+    } else if (any(params$y != 0)) {
       transform_position(data, NULL, function(y) y + params$y)
     } else {
       data # if both x and y are 0 we don't need to transform

tests/testthat/test-position-nudge.R

@@ -1,6 +1,7 @@
 context("position_nudge")
 
 test_that("nudging works in both dimensions simultaneously", {
+  # individual nudge value
   df <- data_frame(x = 1:3)
 
   p <- ggplot(df, aes(x, x, xmax = x, xmin = x, ymax = x, ymin = x)) +
@@ -14,6 +15,22 @@ test_that("nudging works in both dimensions simultaneously", {
   expect_equal(data$y, 3:5)
   expect_equal(data$ymin, 3:5)
   expect_equal(data$ymax, 3:5)
+
+  # multiple nudge values, including zero
+  df <- data_frame(x = c(1, 2, 1))
+
+  p <- ggplot(df, aes(x, x, xmax = x, xmin = x, ymax = x, ymin = x)) +
+    geom_point(position = position_nudge(x = c(0, -1, 0), y = c(0, 1, 2)))
+
+  data <- layer_data(p)
+
+  expect_equal(data$x, c(1, 1, 1))
+  expect_equal(data$xmin, c(1, 1, 1))
+  expect_equal(data$xmax, c(1, 1, 1))
+  expect_equal(data$y, c(1, 3, 3))
+  expect_equal(data$ymin, c(1, 3, 3))
+  expect_equal(data$ymax, c(1, 3, 3))
+
 })
 
 test_that("nudging works in individual dimensions", {
@@ -30,6 +47,17 @@ test_that("nudging works in individual dimensions", {
   expect_equal(data$xmin, 2:4)
   expect_equal(data$xmax, 2:4)
 
+  # multiple nudge values, including zero
+  p <- ggplot(df, aes(x = x, xmax = x, xmin = x)) +
+    layer(geom = Geom, stat = StatIdentity, position = position_nudge(x = c(0, -1, -2)))
+
+  data <- layer_data(p)
+
+  expect_equal(data$x, c(1, 1, 1))
+  expect_equal(data$xmin, c(1, 1, 1))
+  expect_equal(data$xmax, c(1, 1, 1))
+
+
   # nudging in y
   # use an empty layer so can test individual aesthetics
   p <- ggplot(df, aes(y = x, ymax = x, ymin = x)) +
@@ -40,4 +68,15 @@ test_that("nudging works in individual dimensions", {
   expect_equal(data$y, 3:5)
   expect_equal(data$ymin, 3:5)
   expect_equal(data$ymax, 3:5)
+
+  # multiple nudge values, including zero
+  p <- ggplot(df, aes(y = x, ymax = x, ymin = x)) +
+    layer(geom = Geom, stat = StatIdentity, position = position_nudge(y = c(0, -1, -2)))
+
+  data <- layer_data(p)
+
+  expect_equal(data$y, c(1, 1, 1))
+  expect_equal(data$ymin, c(1, 1, 1))
+  expect_equal(data$ymax, c(1, 1, 1))
+
 })