Let parent be optional

Signed-off-by: Matthias Beyer <mail@beyermatthias.de>

1 files changed, 10 insertions, 10 deletions

diff --git a/lib/etc/libimagutil/src/tree.rs b/lib/etc/libimagutil/src/tree.rs
index 42bdd7cf..e8cc9136 100644
--- a/lib/etc/libimagutil/src/tree.rs
+++ b/lib/etc/libimagutil/src/tree.rs
@@ -94,7 +94,7 @@ pub trait IdGetter<T>
     type ID: PartialEq + Sized;
 
     fn get_id_for_node(&self, node: &T)      -> Result<Self::ID>;
-    fn get_id_for_parent_of(&self, node: &T) -> Result<Self::ID>;
+    fn get_id_for_parent_of(&self, node: &T) -> Result<Option<Self::ID>>;
 }
 
 pub struct TreeBuilder<'a, T, ID, IG>(&'a mut Tree<T>, IG)
@@ -110,15 +110,15 @@ impl<'a, T, ID, IG> TreeBuilder<'a, T, ID, IG>
     pub fn build(&mut self) -> Result<()> {
         let mut i = 0;
         while let Some(node) = self.0.elements.get(i) {
-            let parent_id = self.1.get_id_for_parent_of(&node.element)?;
-
-            if let Some(parent_idx) = self.find_node_idx(&parent_id)? {
-                if let Some(parent) = self.0.elements.get_mut(parent_idx) {
-                    parent.childs_indexes.push(i);
-                }
-
-                if let Some(child) = self.0.elements.get_mut(i) {
-                    child.parent_idx = Some(parent_idx);
+            if let Some(parent_id) = self.1.get_id_for_parent_of(&node.element)? {
+                if let Some(parent_idx) = self.find_node_idx(&parent_id)? {
+                    if let Some(parent) = self.0.elements.get_mut(parent_idx) {
+                        parent.childs_indexes.push(i);
+                    }
+
+                    if let Some(child) = self.0.elements.get_mut(i) {
+                        child.parent_idx = Some(parent_idx);
+                    }
                 }
             }