Add fastmap to build()

Author: frederikfabriciusbjerre

R/caugi_graph.R

@@ -268,7 +268,7 @@ caugi_graph <- S7::new_class(
     # initialize fastmap for name to index mapping
     name_index_map <- fastmap::fastmap()
     for (i in seq_len(nrow(nodes))) {
-      name_index_map$set(nodes$name[i], as.integer(id[i]))
+      name_index_map$set(nodes$name[i], i - 1L)
     }
 
     state <- .cg_state(

R/verbs.R

@@ -34,7 +34,8 @@ S7::method(build, caugi_graph) <- function(cg, ...) {
   s <- .unfreeze_state(cg@`.state`)
 
   n <- nrow(s$nodes)
-  id <- setNames(seq_len(n) - 1L, s$nodes$name)
+  id <- seq_len(n) - 1L
+  names(id) <- s$nodes$name
 
   reg <- caugi_registry()
   b <- graph_builder_new(reg, n = n, simple = cg@simple)
@@ -62,6 +63,11 @@ S7::method(build, caugi_graph) <- function(cg, ...) {
   ) |>
     dplyr::arrange(from, to, edge)
 
+  name_index_map <- fastmap::fastmap()
+  for (i in seq_len(nrow(s$nodes))) {
+    name_index_map$set(s$nodes$name[i], i - 1L)
+  }
+  s$name_index_map <- name_index_map
   s$ptr <- p
   s$built <- TRUE
   .freeze_state(cg@`.state`)

tests/testthat/test-verbs.R

@@ -43,6 +43,26 @@ test_that("build() errors when breaking simple graph assumptions", {
   expect_error(build(cg), "self-loop")
 })
 
+test_that("build updates name_index_map", {
+  # start with a built graph
+  cg <- caugi_graph(from = "A", edge = "-->", to = "B")
+  expect_true(cg@built)
+  expect_identical(cg@name_index_map$get("A"), 0L)
+  expect_identical(cg@name_index_map$get("B"), 1L)
+
+  # mutate graph → not built, fastmap still stale
+  cg <- add_nodes(cg, name = "C")
+  expect_false(cg@built)
+  expect_null(cg@name_index_map$get("C"))
+
+  # rebuild → fastmap must include the new node with correct index
+  cg <- build(cg)
+  expect_true(cg@built)
+  expect_identical(cg@name_index_map$get("A"), 0L)
+  expect_identical(cg@name_index_map$get("B"), 1L)
+  expect_identical(cg@name_index_map$get("C"), 2L)
+})
+
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