Provide a better error message when deleting nonexistent attributes

If --delattr is used on an attribute that's not present on an entry,
and --{set,add}attr isn't being used on that same attribute,
say that there's "no such attribute" instead of "<attribute> does
not contain <value>".

https://fedorahosted.org/freeipa/ticket/2699

ipalib/plugins/baseldap.py

@@ -906,6 +906,16 @@ last, after all sets and adds."""),
                 )
             except errors.NotFound:
                 self.obj.handle_not_found(*keys)
+
+            # Provide a nice error message when user tries to delete an
+            # attribute that does not exist on the entry (and user is not
+            # adding it)
+            names = set(n.lower() for n in old_entry)
+            del_nonexisting = delattrs - (names | setattrs | addattrs)
+            if del_nonexisting:
+                raise errors.ValidationError(name=del_nonexisting.pop(),
+                    error=_('No such attribute on this entry'))
+
             for attr in needldapattrs:
                 entry_attrs[attr] = old_entry.get(attr, [])
 

tests/test_xmlrpc/test_attr.py

@@ -518,4 +518,37 @@ class test_attr(Declarative):
                 error='must be an integer'),
         ),
 
+        dict(
+            desc='Try deleting bogus attribute',
+            command=('config_mod', [], dict(delattr=u'bogusattribute=xyz')),
+            expected=errors.ValidationError(name='bogusattribute',
+                error='No such attribute on this entry'),
+        ),
+
+        dict(
+            desc='Try deleting empty attribute',
+            command=('config_mod', [],
+                dict(delattr=u'ipaCustomFields=See Also,seealso,false')),
+            expected=errors.ValidationError(name='ipacustomfields',
+                error='No such attribute on this entry'),
+        ),
+
+        dict(
+            desc='Set and delete one value, plus try deleting a missing one',
+            command=('config_mod', [], dict(
+                delattr=[u'ipaCustomFields=See Also,seealso,false',
+                    u'ipaCustomFields=Country,c,false'],
+                addattr=u'ipaCustomFields=See Also,seealso,false')),
+            expected=errors.AttrValueNotFound(attr='ipacustomfields',
+                value='Country,c,false'),
+        ),
+
+        dict(
+            desc='Try to delete an operational attribute with --delattr',
+            command=('config_mod', [], dict(
+                delattr=u'creatorsName=cn=directory manager')),
+            expected=errors.DatabaseError(
+                desc='Server is unwilling to perform', info=''),
+        ),
+
     ]