Additional comments and coverage for Activation methods

interpreter/activation.go

@@ -178,6 +178,7 @@ func (a *partActivation) AsPartialActivation() (PartialActivation, bool) {
 	return a, true
 }
 
+// AsPartialActivation walks the activation hierarchy and returns the first PartialActivation, if found.
 func AsPartialActivation(vars Activation) (PartialActivation, bool) {
 	// Only internal activation instances may implement this interface
 	if pv, ok := vars.(partialActivationConverter); ok {

interpreter/activation_test.go

@@ -63,6 +63,25 @@ func TestActivation_ResolveLazy(t *testing.T) {
 	}
 }
 
+func TestActivation_ResolveLazyAny(t *testing.T) {
+	var v any
+	now := func() any {
+		if v == nil {
+			v = time.Now().Unix()
+		}
+		return v
+	}
+	a, _ := NewActivation(map[string]any{
+		"now": now,
+	})
+	first, _ := a.ResolveName("now")
+	second, _ := a.ResolveName("now")
+	if first != second {
+		t.Errorf("Got different second, "+
+			"expected same as first: 1:%v 2:%v", first, second)
+	}
+}
+
 func TestHierarchicalActivation(t *testing.T) {
 	// compose a parent with more properties than the child
 	parent, _ := NewActivation(map[string]any{
@@ -89,3 +108,25 @@ func TestHierarchicalActivation(t *testing.T) {
 		t.Error("Activation failed to resolve child value of 'c'")
 	}
 }
+
+func TestAsPartialActivation(t *testing.T) {
+	// compose a parent with more properties than the child
+	parent, _ := NewPartialActivation(map[string]any{
+		"a": types.String("world"),
+		"b": types.Int(-42),
+	}, NewAttributePattern("c"))
+	// compose the child such that it shadows the parent
+	child, _ := NewActivation(map[string]any{
+		"d": types.String("universe"),
+	})
+	combined := NewHierarchicalActivation(parent, child)
+
+	// Resolve the shadowed child value.
+	if part, found := AsPartialActivation(combined); found {
+		if part != parent {
+			t.Errorf("AsPartialActivation() got %v, wanted %v", part, parent)
+		}
+	} else {
+		t.Error("AsPartialActivation() failed, did not find parent partial activation")
+	}
+}