Fix generators.

jedi/evaluate/__init__.py

@@ -164,6 +164,7 @@ class Evaluator(object):
         debug.dbg('eval_statement result %s', types)
         return types
 
+    @memoize_default(evaluator_is_first_arg=True)
     def eval_element(self, element):
         debug.dbg('eval_element %s', element)
         if isinstance(element, (pr.Name, pr.Literal)) or pr.is_node(element, 'atom'):

jedi/evaluate/iterable.py

@@ -84,7 +84,8 @@ class Generator(use_metaclass(CachedMetaClass, IterableWrapper, GeneratorMixin))
         # Directly execute it, because with a normal call to py__call__ a
         # Generator will be returned.
         from jedi.evaluate.representation import FunctionExecution
-        return FunctionExecution(self._evaluator, self.func, self.var_args).get_return_types()
+        f = FunctionExecution(self._evaluator, self.func, self.var_args)
+        return f.get_return_types(check_yields=True)
 
     def __getattr__(self, name):
         if name not in ['start_pos', 'end_pos', 'parent', 'get_imports',

jedi/evaluate/recursion.py

@@ -100,12 +100,12 @@ class _RecursionNode(object):
 
 
 def execution_recursion_decorator(func):
-    def run(execution):
+    def run(execution, **kwargs):
         detector = execution._evaluator.execution_recursion_detector
         if detector.push_execution(execution):
             result = []
         else:
-            result = func(execution)
+            result = func(execution, **kwargs)
         detector.pop_execution()
         return result
 

jedi/evaluate/representation.py

@@ -567,7 +567,7 @@ class FunctionExecution(Executed):
 
     @memoize_default(default=())
     @recursion.execution_recursion_decorator
-    def get_return_types(self):
+    def get_return_types(self, check_yields=False):
         func = self.base
 
         if func.listeners:
@@ -579,8 +579,14 @@ class FunctionExecution(Executed):
             # inserted params, not in the actual execution of the function.
             return []
 
-        types = list(docstrings.find_return_types(self._evaluator, func))
-        for r in self.returns:
+        if check_yields:
+            types = []
+            returns = self.yields
+        else:
+            returns = self.returns
+            types = list(docstrings.find_return_types(self._evaluator, func))
+
+        for r in returns:
             check = flow_analysis.break_check(self._evaluator, self, r)
             if check is flow_analysis.UNREACHABLE:
                 debug.dbg('Return unreachable: %s', r)
@@ -661,6 +667,11 @@ class FunctionExecution(Executed):
     def returns(self):
         return self._copy_list(self.base.returns)
 
+    @common.safe_property
+    @memoize_default([])
+    def yields(self):
+        return self._copy_list(self.base.yields)
+
     @common.safe_property
     @memoize_default([])
     def children(self):