Code cleanup

* Remove object subclassing
* Move method makenode() to Expr class where it corresponds
* Removes ununsed __deepcopy method
* Adds typing for children
* Adds parent attribute (which is alread used!)

Author: boriel

ast_/tree.py

@@ -1,8 +1,8 @@
 #!/usr/bin/python
 # -*- coding: utf-8 -*-
 
+from typing import Optional
 
-import copy
 import collections
 from api.errors import Error
 
@@ -21,11 +21,13 @@ def __str__(self):
         return self.msg
 
 
-class Tree(object):
+class Tree:
     """ Simple tree implementation
     """
-    class childrenList(object):
-        def __init__(self, node):
+    parent: Optional['Tree'] = None
+
+    class ChildrenList:
+        def __init__(self, node: 'Tree'):
             assert isinstance(node, Tree)
             self.node = node  # Node having this children
             self._children = []
@@ -34,7 +36,7 @@ def __getitem__(self, key):
             if isinstance(key, int):
                 return self._children[key]
 
-            result = Tree.childrenList(self.node)
+            result = Tree.ChildrenList(self.node)
             for x in self._children[key]:
                 result.append(x)
             return result
@@ -68,10 +70,10 @@ def __len__(self):
             return len(self._children)
 
         def __add__(self, other):
-            if not isinstance(other, Tree.childrenList):
+            if not isinstance(other, Tree.ChildrenList):
                 assert isinstance(other, collections.Container)
 
-            result = Tree.childrenList(self.node)
+            result = Tree.ChildrenList(self.node)
             for x in self:
                 result.append(x)
             for x in other:
@@ -82,19 +84,19 @@ def __repr__(self):
             return "%s:%s" % (self.node.__repr__(), str([x.__repr__() for x in self._children]))
 
     def __init__(self):
-        self._children = Tree.childrenList(self)
+        self._children = Tree.ChildrenList(self)
 
     @property
     def children(self):
         return self._children
 
     @children.setter
     def children(self, value):
-        assert isinstance(value, collections.Container)
+        assert isinstance(value, collections.Iterable)
         while len(self.children):
             self.children.pop()
 
-        self._children = Tree.childrenList(self)
+        self._children = Tree.ChildrenList(self)
         for x in value:
             self.children.append(x)
 
@@ -131,24 +133,3 @@ def prependChild(self, node):
         """ Inserts the given node at the beginning of the children list
         """
         self.children.insert(0, node)
-
-    @classmethod
-    def makenode(cls, symbol, *nexts):
-        """ Stores the symbol in an AST instance,
-        and left and right to the given ones
-        """
-        result = cls(symbol)
-        for i in nexts:
-            if i is None:
-                continue
-            if not isinstance(i, cls):
-                raise NotAnAstError(i)
-            result.appendChild(i)
-
-        return result
-
-    def __deepcopy(self, memo):
-        result = Tree(self.symbol)  # No need to duplicate the symbol memory
-        result.next = copy.deepcopy(self.children)
-
-        return result