related to issue #16: removed the need to replicate information about…

… the class identified by a relation.

bauble/plugins/plants/__init__.py

@@ -47,7 +47,7 @@ def init(cls):
                                          context_menu=family_context_menu,
                                          markup_func=family_markup_func)
 
-        mapper_search.add_meta(('genus', 'gen', 'genera'), Genus, ['genus'])
+        mapper_search.add_meta(('genus', 'gen'), Genus, ['genus'])
         SearchView.view_meta[Genus].set(children="species",
                                         infobox=GenusInfoBox,
                                         context_menu=genus_context_menu,

bauble/search.py

@@ -86,14 +86,22 @@ def __repr__(self):
         return '.'.join(self.value)
 
     def evaluate(self, env):
+        """return pair (query, attribute)
+
+        the value associated to the identifier is an altered query where the
+        joinpoint is the one relative to the attribute, and the attribute
+        itself.
+        """
+
+        query = env.session.query(env.domain)
         if len(self.value) == 1:
             # identifier is an attribute of the table being queried
-            return getattr(env.domain, self.value[0])
+            attr = getattr(env.domain, self.value[0])
         elif len(self.value) > 1:
             # identifier is an attribute of a joined table
-            domain = env.search_strategy._shorthand.get(self.value[-2], self.value[-2])
-            domain = env.search_strategy._domains[domain][0]
-            return getattr(domain, self.value[-1])
+            query = query.join(*self.value[:-1], aliased=True)
+            attr = getattr(query._joinpoint['_joinpoint_entity'], self.value[-1])
+        return query, attr
 
     def needs_join(self, env):
         return self.value[:-1]
@@ -117,9 +125,8 @@ def __repr__(self):
         return "(%s %s %s)" % ( self.operands[0], self.op, self.operands[1])
 
     def evaluate(self, env):
-        clause = lambda x: self.operation(self.operands[0].evaluate(env), x)
-        q = env.session.query(env.domain)
-        q = q.join(*self.operands[0].needs_join(env))
+        q, a = self.operands[0].evaluate(env)
+        clause = lambda x: self.operation(a, x)
         return q.filter(clause(self.operands[1].express()))
 
     def needs_join(self, env):