X treegen: Verify that tree actually saved to storage is what was requested

wcfs/testprog/treegen.py

@@ -194,7 +194,19 @@ def Trees(zstor, r):
         # restructure ztree to requested topology
         xbtree.Restructure(ztree, tree)
 
+        # commit tree to storage
         head = commit("treegen/trees: %s" % treetxt)
+
+        # verify what was persisted to storage is indeed what we intended
+        zctx.zconn.cacheMinimize()
+        treetxt_onstor = zctx.ztreetxt(ztree)
+        if treetxt_onstor != treetxt:
+            panic("BUG: tree wrongly saved to storage:\nsaved:     %s\nrequested: %s" %
+                    (treetxt_onstor, treetxt))
+        # verify saved tree consistency
+        xbtree.zcheck(ztree)
+
+        # ok
         xprint("%s" % ashex(head))