[selector] make select a hardcoded argument, and propaget it (see #6)

aggregator.py

@@ -5,7 +5,6 @@ from functools import partial
 from mypool import MyPool
 
 from postprocessor import PostProcessor
-from run_selector import RunSelector
 
 
 def _map_rule(rule, arg, overwrite, path, path_out, pp_params, run_num):
@@ -20,17 +19,9 @@ def _map_rule(rule, arg, overwrite, path, path_out, pp_params, run_num):
 
 
 class Aggregator:
-    def _not_self_dep(self, name, dep, dep_arg, overwrite, **kwargs):
-        if "select" in kwargs:
-            select = kwargs["select"]
+    def _not_self_dep(self, name, dep, dep_arg, overwrite, select):
+        if select is not None:
             runs, nums = self.selector.select(**select)
-        elif "runs" in kwargs:
-            runs = kwargs["runs"]
-            if isinstance(runs, RunSelector):
-                nums = runs.nums
-                runs = runs.runs
-            else:
-                nums = self.nums
         else:
             runs = self.runs
             nums = self.nums