.

wcfs/internal/xbtree.py

@@ -52,11 +52,20 @@ class Tree:
     def __hash__(t):
         return hash(t.keyv) ^ hash(t.children)                      # XXX children ^^^
 
+    def __str__(t):
+        s = "T([" + ",".join(['%s' % _ for _ in t.keyv]) + "]"
+        for ch in t.children:
+            s += ",\n"
+            s += _indent(' '*4, str(ch))
+        s += ")"
+        return s
+
+    __repr__ = __str__
 
 # Bucked represents a bucket node.
 class Bucket:
     #   .keyv   () of keys
-    def __init__(b, keyv):
+    def __init__(b, *keyv):     # XXX *keyv -> keyv ?
         # XXX assert keyv ↑
         b.keyv = tuple(keyv)
 
@@ -67,6 +76,11 @@ class Bucket:
     def __hash__(b):
         return hash(b.keyv)
 
+    def __str__(b):
+        return "B(" + ','.join(['%s' % _ for _ in b.keyv]) + ")"
+
+    __repr__ = __str__
+
 
 # StructureOf returns internal structure of a tree.
 def StructureOf(node):
@@ -80,7 +94,7 @@ def StructureOf(node):
 
     if is_bucket:
         keys, _ = bcheck.crack_bucket(node, is_map)
-        return Bucket(keys)
+        return Bucket(*keys)
 
     if is_tree:
         kind, keys, children = bcheck.crack_btree(node, is_map)
@@ -108,3 +122,14 @@ def TypologyOf(tree):
     1/0
     treeStruct = StructureOf(tree)
     # XXX convert struct -> topology
+
+
+
+# ---- misc ----
+
+# _indent returns text with each line of it indented with prefix.
+def _indent(prefix, text): # -> text
+    textv = text.split('\n')
+    textv = [prefix+_ for _ in textv]
+    text  = '\n'.join(textv)
+    return text

wcfs/internal/xbtree_test.py

@@ -23,6 +23,7 @@ from BTrees.tests import testBTrees
 
 def test_topologyOf():
     T = xbtree.Tree
+    B = xbtree.Bucket
 
     # XXX empty
 
@@ -36,12 +37,12 @@ def test_topologyOf():
 
     assert xbtree.StructureOf(t) == T([4],
                                        T([2],
-                                            T([]), T([])),
+                                            T([], B(1)), T([], B(3))),
                                        T([],
                                             T([6, 10],
-                                                T([], T([])),
-                                                T([]),
-                                                T([])) ))
+                                                T([], T([], B(5))),
+                                                T([], B(7)),
+                                                T([], B(11))) ))
 
     """
     assert xbtree.TopologyOf(t) == ( (4,),