debug cumulate + add test + update news - fix #146

Author: corybrunson

DESCRIPTION

@@ -1,7 +1,7 @@
 Package: ggalluvial
 Type: Package
 Title: Alluvial Plots in 'ggplot2'
-Version: 0.12.5
+Version: 0.12.5.0001
 Authors@R: c(
     person(given = "Jason Cory",
            family = "Brunson",

NEWS.md

@@ -8,6 +8,10 @@ The paramater `outline.type` from `ggplot2::geom_ribbon()` has been adapted to `
 
 The tests that use the `Refugees` data set from **alluvial** are now only run if that package is installed; see #131 and thanks to @MichaelChirico.
 
+## `cumulate()` fix
+
+The `cumulate()` function previously broke if an axis had zero total alluvial height (#146); it has been debugged.
+
 # ggalluvial 0.12.5
 
 This patch fixes a bug involving the {dplyr} functions `first()` and `last()` that was shifted but not fixed in 0.12.4. Rather than being imported during build, they are accessed internally and thus imported during use. See issues #107 <https://github.com/corybrunson/ggalluvial/issues/107> and #108 <https://github.com/corybrunson/ggalluvial/issues/108> on GitHub for details.

R/stat-utils.r

@@ -90,6 +90,7 @@ deposit_data <- function(data, decreasing, reverse, absolute) {
 # calculate cumulative 'y' values, accounting for sign
 cumulate <- function(x) {
   if (length(x) == 0) return(x)
+  if (all(x == 0)) return(rep(0, length(x)))
   s <- setdiff(unique(sign(x)), 0)
   stopifnot(length(s) == 1 && s %in% c(-1, 1))
   if (s == 1) {

tests/testthat/test-stat-alluvium.r

@@ -88,3 +88,16 @@ test_that("`stat_flow` handles exceptional data with out errors", {
     geom_alluvium(aes(fill = country))
   expect_silent(ggplot_build(gg))
 })
+
+d <- data.frame(
+  subject = rep(c("A", "B"), each = 2),
+  time = rep(1:2, times = 2),
+  status = factor(c("a", "b", "b", "a")),
+  value = c(0, 1, 0, 2)
+)
+test_that("`stat_alluvium` handles axes with zero total height", {
+  gg <-
+    ggplot(d, aes(x = time, stratum = status, alluvium = subject, y = value)) +
+    stat_alluvium(aes(fill = subject))
+  expect_silent(ggplot_build(gg))
+})