neo4j/graph: Optimize some services of `SequentialNodeCollection`.

Signed-off-by: Jean-Christophe Beaupré <jcbrinfo@users.noreply.github.com>

diff --git a/lib/neo4j/graph/sequential_id.nit b/lib/neo4j/graph/sequential_id.nit
index 3b3559a..0bcaa6c 100644 (file)
--- a/lib/neo4j/graph/sequential_id.nit
+++ b/lib/neo4j/graph/sequential_id.nit
@@ -36,6 +36,7 @@ private import pipeline
 # assert b["id"] == 2
 # assert c["id"] == 4
 # assert nodes.to_a == [a, b, c]
+# assert nodes.length == 3
 # ~~~
 class SequentialNodeCollection
        super NeoNodeCollection
@@ -44,16 +45,25 @@ class SequentialNodeCollection
 
        private var nodes = new Array[nullable NeoNode]
 
+       redef var length = 0
+
        redef fun iterator do return new NullSkipper[NeoNode](self.nodes.iterator)
 
+       redef fun [](id) do return nodes[id].as(NeoNode)
+
        redef fun get_or_null(id) do
                if id < 0 or id > nodes.length then return null
                return nodes[id]
        end
 
+       redef fun has_id(id: Int): Bool do
+               return id >= 0 and id < nodes.length and nodes[id] isa NeoNode
+       end
+
        redef fun register(node) do
                nodes.add node
                id_of(node) = nodes.length
+               length += 1
        end
 
        redef fun add(node) do
@@ -65,15 +75,23 @@ class SequentialNodeCollection
                        sys.stderr.write "The local ID must be greater or equal to 0. Got {id}.\n"
                end
                # Pad with nulls.
+               nodes.enlarge(id)
                var delta = id - nodes.length
                while delta > 0 do
                        nodes.add null
                        delta -= 1
                end
                nodes[id] = node
+               length += 1
        end
 
        redef fun remove_at(id) do
                nodes[id] = null
+               length -= 1
+       end
+
+       redef fun clear do
+               nodes.clear
+               length = 0
        end
 end