.

wcfs/internal/xbtree.py

@@ -185,12 +185,23 @@ def StructureOf(node):
     panic("unknown node type %r" % typ)
 
 
-# Restructure reorganizes BTree instance (not Tree) according to new structure.
-def Restructure(tree, newStructure):
-    assert istree(tree)
+# Restructure reorganizes ZODB BTree instance (not Tree) according to specified
+# structure.
+def Restructure(ztree, newStructure):
+    assert istree(ztree)    # XXX -> use bcheck.classify
     assert isinstance(newStructure, Tree)
     1/0
 
+    _bcheck(ztree)  # verify ztree before our tweaks
+
+
+    _bcheck(ztree)  # verify ztree after our tweaks
+    tstruct = StructureOf(ztree)
+    if tstruct != newStructure:
+        panic("BUG: Restructure: result structure is not what was"
+              "requested:\n%s\n\nwant:\n%s" % (tstruct, newStructure))
+
+
 # AllStructs generates subset of all possible BTree structures for BTrees with
 # specified keys and btree depth up-to maxdepth. Each tree node is split by
 # up-to maxsplit points.
@@ -399,6 +410,21 @@ def _assertIncv(v):
         prev = v[i]
 
 
+# _bcheck performs checks on ztree provided by ZODB packages.
+# the checks are what BTree.check and node._check() provide.
+class _ZChecker(_bcheck.Checker):
+    def visit_btree(self, obj, *argv):
+        super(_ZChecker, self).visit_btree(obj, *argv)
+        obj._check() # also check internal C-level pointers consistency
+
+    def visit_bucket(self, obj, *argv):
+        super(_ZChecker, self).visit_bucket(obj, *argv)
+        obj._check() # ----//-----
+
+def _bcheck(ztree):
+    _ZChecker(ztree).check()
+    _bcheck.check(ztree)
+