compute pseudoheight tweaks

wcharczuk · Feb 24, 2024 · a1e1963 · a1e1963
1 parent b92543a
commit a1e1963
Show file tree

Hide file tree

Showing 2 changed files with 19 additions and 0 deletions.
diff --git a/expert_node.go b/expert_node.go
@@ -205,6 +205,10 @@ func (en *expertNode) computePseudoHeightCached(cache map[Identifier]int, n INod
 		return height
 	}
 
+	if len(nn.parents) == 0 {
+		return 0
+	}
+
 	var maxParentHeight int
 	for _, p := range nn.parents {
 		parentHeight := en.computePseudoHeightCached(cache, p)

diff --git a/expert_node_test.go b/expert_node_test.go
@@ -89,3 +89,18 @@ func Test_ExpertNode_Value(t *testing.T) {
 	value := en.Value()
 	testutil.Equal(t, "hello", value)
 }
+
+func Test_ExpertNode_ComputePseudoheight(t *testing.T) {
+	g := New()
+
+	r00 := Return(g, "r")
+	m10 := Map(g, r00, ident)
+	m20 := Map(g, m10, ident)
+	m30 := Map(g, m20, ident)
+
+	_ = MustObserve(g, m30)
+
+	testutil.Equal(t, m10.Node().height, ExpertNode(m10).ComputePseudoHeight())
+	testutil.Equal(t, m20.Node().height, ExpertNode(m20).ComputePseudoHeight())
+	testutil.Equal(t, m30.Node().height, ExpertNode(m30).ComputePseudoHeight())
+}