fix missing dependencies bug

datajoint/dependencies.py

@@ -1,6 +1,19 @@
 from collections import defaultdict
 import pyparsing as pp
 from . import DataJointError
+from functools import wraps
+
+def load_dependencies(func):
+    """
+    Decorator that ensures that dependencies are loaded
+    """
+
+    @wraps(func)
+    def f(*args, **kwargs):
+        args[0].load()
+        return func(*args, **kwargs)
+    return f
+
 
 
 class Dependencies:
@@ -17,20 +30,25 @@ def __init__(self, conn):
         self._children = defaultdict(list)
         self._references = defaultdict(list)
 
+
     @property
+    @load_dependencies
     def parents(self):
         return self._parents
 
 
     @property
+    @load_dependencies
     def children(self):
         return self._children
 
     @property
+    @load_dependencies
     def references(self):
         return self._references
 
     @property
+    @load_dependencies
     def referenced(self):
         return self._referenced