Move away from inodes as direct db reference

trovedb/trovedb.py

@@ -11,7 +11,7 @@ from pathlib import Path
 
 from .db import Sqlite3Trove
 from .tree import Tree as TreeData
-from .trove import NODE_ROOT_ID, Note, Trove, TreeNote, BlobNote
+from .trove import NODE_ROOT_ID, Note, Trove, TreeNote, BlobNote, TreeEntry, NoteNotFound
 
 
 class NoteImpl(Note):
@@ -65,9 +65,12 @@ class TreeNoteImpl(NoteImpl, TreeNote):
 
     def unlink(self, name: str) -> None:
         """Remove an entry by name. Raises KeyError if not found."""
-        tree = self._read_tree()
-        tree.rm_entry(name)
-        self._flush_tree(tree)
+        try:
+            tree = self._read_tree()
+            tree.rm_entry(name)
+            self._flush_tree(tree)
+        except KeyError:
+            pass
 
     def mkdir(self, name: str) -> 'TreeNoteImpl':
         """Create a new empty tree, link it under name, and return it."""
@@ -91,7 +94,16 @@ class TreeNoteImpl(NoteImpl, TreeNote):
         if name not in entries:
             raise KeyError(f"Entry '{name}' not found")
         child_id = entries[name]
-        return self._parent.get_raw_note(child_id)
+        value = self._parent.get_raw_note(child_id)
+        if value is None:
+            raise KeyError(f"Entry '{name}' has no value")
+        return value
+
+    def entries(self):
+        """Return all entries as an iterable of TreeEntry."""
+        tree = self._read_tree()
+        for name, object_id in tree.list().items():
+            yield TreeEntry(name, object_id)
 
     def list(self) -> dict[str, int]:
         """Return all entries as {name: object_id}."""
@@ -138,11 +150,11 @@ class TroveImpl:
         self.close()
 
     # Trove protocol
-    def get_raw_note(self, note_id: int) -> Optional[Note]:
+    def get_raw_note(self, note_id: int) -> Note:
         """Return a BlobNote or TreeNote for the given id, or None if not found."""
         ot = self._db.get_object_type(note_id)
         if ot is None:
-            return None
+            raise NoteNotFound(note_id)
         if ot == "blob":
             return BlobNoteImpl(self, note_id)
         if ot == "tree":