find should always return a full primitive

lib/scenic/graph.ex

@@ -583,10 +583,29 @@ defmodule Scenic.Graph do
   """
 
   @spec find(graph :: t(), (any -> as_boolean(term()))) :: list(Primitive.t())
-  def find(graph, finder)
+  def find(%__MODULE__{} = graph, finder) do
+    reduce(graph, [], fn p, acc ->
+      p
+      |> finder.()
+      |> case do
+        true -> [p | acc]
+        false -> acc
+      end
+    end)
+    |> Enum.reverse()
+  end
 
-  # pass in an atom based id, and it will transform all mapped uids
-  def find(%__MODULE__{} = graph, finder) when is_function(finder, 1) do
+  @doc """
+  Find one or more primitives in a graph by id via a filter function.
+
+  Pass in a function that accepts a primitive's id and returns a boolean.
+
+  Returns a list of primitives.
+
+  __Warning:__ This function crawls the entire graph and is thus slower than
+  accessing items via a fully-specified id.
+  """
+  def find_by_id(%__MODULE__{} = graph, finder) do
     reduce(graph, [], fn p, acc ->
       Map.get(p, :id)
       |> finder.()
@@ -652,7 +671,7 @@ defmodule Scenic.Graph do
   # pass in a finder function
   def modify(%__MODULE__{} = graph, finder, action) when is_function(finder, 1) do
     graph
-    |> find(finder)
+    |> find_by_id(finder)
     |> Enum.map(fn %{id: id} -> id end)
     |> Enum.uniq()
     |> Enum.reduce(graph, &modify(&2, &1, action))

test/scenic/graph_test.exs

@@ -267,20 +267,38 @@ defmodule Scenic.GraphTest do
   end
 
   # ============================================================================
-  test "find returns the matching items" do
+    test "find returns the matching items" do
+      graph =
+        Graph.build()
+        |> Text.add_to_graph("text one", id: {:a, :one})
+        |> Text.add_to_graph("text two", id: {:a, :two})
+        |> Text.add_to_graph("text three", id: {:b, :three})
+
+      # confirm result
+      assert Graph.find(graph, &match?({:a, :one}, &1.id)) == [
+        Graph.get!(graph, {:a, :one})
+      ]
+
+      assert Graph.find(graph, &match?({:b, :three}, &1.id)) == [
+        Graph.get!(graph, {:b, :three})
+      ]
+    end
+
+  # ============================================================================
+  test "find_by_id returns the matching items" do
     graph =
       Graph.build()
       |> Text.add_to_graph("text one", id: {:a, :one})
       |> Text.add_to_graph("text two", id: {:a, :two})
       |> Text.add_to_graph("text three", id: {:b, :three})
 
     # confirm result
-    assert Graph.find(graph, &match?({:a, _}, &1)) == [
+    assert Graph.find_by_id(graph, &match?({:a, _}, &1)) == [
              Graph.get!(graph, {:a, :one}),
              Graph.get!(graph, {:a, :two})
            ]
 
-    assert Graph.find(graph, &match?({:b, _}, &1)) == [
+    assert Graph.find_by_id(graph, &match?({:b, _}, &1)) == [
              Graph.get!(graph, {:b, :three})
            ]
   end