ENH: fixed bugs in compare function and enhanced the description of a diff of two records

src/caosdb/apiutils.py

@@ -550,6 +550,12 @@ def compare_entities(old_entity, new_entity):
         except BaseException:
             new_entity_attr_exists = False
 
+        if old_entity_attr_exists and (oldattr == "" or oldattr is None):
+            old_entity_attr_exists = False
+
+        if new_entity_attr_exists and (newattr == "" or newattr is None):
+            new_entity_attr_exists = False
+
         if not old_entity_attr_exists and not new_entity_attr_exists:
             continue
 
@@ -571,6 +577,7 @@ def compare_entities(old_entity, new_entity):
             olddiff["properties"][prop.name] = {}
         elif len(matching) == 1:
             newdiff["properties"][prop.name] = {}
+            olddiff["properties"][prop.name] = {}
 
             if (old_entity.get_importance(prop.name) !=
                     new_entity.get_importance(prop.name)):
@@ -585,6 +592,12 @@ def compare_entities(old_entity, new_entity):
                 olddiff["properties"][prop.name]["datatype"] = prop.datatype
                 newdiff["properties"][prop.name]["datatype"] = \
                     matching[0].datatype
+
+            if (len(newdiff["properties"][prop.name]) == 0
+                    and len(olddiff["properties"][prop.name]) == 0):
+                newdiff["properties"].pop(prop.name)
+                olddiff["properties"].pop(prop.name)
+
         else:
             raise NotImplementedError()
 
@@ -605,10 +618,10 @@ def compare_entities(old_entity, new_entity):
     return (olddiff, newdiff)
 
 
-def describe_diff(olddiff, newdiff, as_update=True):
-    description = "## Difference between the old and the new version of {}\n\n"
+def describe_diff(olddiff, newdiff, name=None, as_update=True):
+    description = ""
 
-    for attr in list(set(list(olddiff.keys)+list(newdiff.keys))):
+    for attr in list(set(list(olddiff.keys())+list(newdiff.keys()))):
         if attr == "parents" or attr == "properties":
             continue
         description += "{} differs:\n".format(attr)
@@ -625,12 +638,22 @@ def describe_diff(olddiff, newdiff, as_update=True):
         description += ("Parents that are only in the new version:\n"
                         + ", ".join(olddiff["parents"]))
 
-    for prop in list(set(list(olddiff["properties"].keys)
-                         + list(newdiff["properties"].keys))):
+    for prop in list(set(list(olddiff["properties"].keys())
+                         + list(newdiff["properties"].keys()))):
         description += "property {} differs:\n".format(prop)
-        description += "old version: {}\n".format(
-            olddiff["properties"][prop] if prop
-            in olddiff["properties"] else "has none")
-        description += "new version: {}\n\n".format(
-            newdiff["properties"][prop] if prop
-            in newdiff["properties"] else "has none")
+
+        if prop not in olddiff["properties"]:
+            description += "it does not exist in the old version: \n"
+        elif prop not in newdiff["properties"]:
+            description += "it does not exist in the new version: \n"
+        else:
+            description += "old version: {}\n".format(
+                olddiff["properties"][prop])
+            description += "new version: {}\n\n".format(
+                newdiff["properties"][prop])
+
+    if description != "":
+        description = ("## Difference between the old and the new "
+                       "version of {}\n\n".format(name))+description
+
+    return description