Shorten leaf node function (previously next_targets())

ropensci · Nov 24, 2017 · 867f643 · 867f643
1 parent 2badae8
commit 867f643
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Showing 4 changed files with 7 additions and 17 deletions.
diff --git a/NAMESPACE b/NAMESPACE
@@ -132,6 +132,7 @@ importFrom(grDevices,col2rgb)
 importFrom(grDevices,rgb)
 importFrom(igraph,V)
 importFrom(igraph,adjacent_vertices)
+importFrom(igraph,degree)
 importFrom(igraph,delete_vertices)
 importFrom(igraph,edge)
 importFrom(igraph,is_dag)

diff --git a/R/dataframes_graph_utils.R b/R/dataframes_graph_utils.R
@@ -161,7 +161,7 @@ resolve_levels <- function(config) {
     keep_these <- setdiff(V(graph)$name, rownames(nodes))
     graph_remaining_targets <- delete_vertices(graph, v = keep_these)
     while (length(V(graph_remaining_targets))) {
-      candidates <- next_targets(graph_remaining_targets, jobs = jobs)
+      candidates <- leaf_nodes(graph = graph_remaining_targets)
       if (length(candidates)){
         nodes[candidates, "level"] <- level
         level <- level + 1

diff --git a/R/package.R b/R/package.R
@@ -37,7 +37,7 @@
 #' @importFrom formatR tidy_source
 #' @importFrom future future_lapply plan
 #' @importFrom grDevices col2rgb rgb
-#' @importFrom igraph adjacent_vertices delete_vertices edge
+#' @importFrom igraph adjacent_vertices delete_vertices degree edge
 #' is_dag make_empty_graph plot.igraph subcomponent V vertex
 #' @importFrom knitr knit
 #' @importFrom lubridate dseconds duration

diff --git a/R/parallel.R b/R/parallel.R
@@ -15,8 +15,7 @@ run_parallel <- function(config, worker) {
 }
 
 parallel_stage <- function(worker, config) {
-  candidates <- next_targets(
-    config$graph_remaining_targets, jobs = config$jobs)
+  candidates <- leaf_nodes(graph = config$graph_remaining_targets)
   meta_list <- meta_list(targets = candidates, config = config, store = TRUE)
   should_build <- lightly_parallelize(
     X = candidates,
@@ -57,19 +56,9 @@ exclude_imports_if <- function(config){
   config
 }
 
-next_targets <- function(graph_remaining_targets, jobs = 1){
-  number_dependencies <- lightly_parallelize(
-    X = V(graph_remaining_targets),
-    FUN = function(x){
-      adjacent_vertices(graph_remaining_targets, x, mode = "in") %>%
-        unlist() %>%
-        length()
-    },
-    jobs = jobs
-  ) %>%
-    unlist
-  which(!number_dependencies) %>%
-    names()
+leaf_nodes <- function(graph){
+  is_leaf <- igraph::degree(graph, mode = "in") == 0
+  V(graph)[is_leaf]$name
 }
 
 lightly_parallelize <- function(X, FUN, jobs = 1, ...) {