fix a default argument issue

jedi/evaluate/param.py

@@ -170,10 +170,11 @@ def get_params(evaluator, func, var_args):
         # about the values inside, it's about the names. Jedi needs to now that
         # there's nothing to find for certain names.
         for k in set(param_dict) - keys_used:
-            result.append(_gen_param_name_copy(func, var_args, param_dict[k]))
+            param = param_dict[k]
+            result.append(_gen_param_name_copy(func, var_args, param))
 
             if not (non_matching_keys or had_multiple_value_error
-                    or param_dict[k].stars):
+                    or param.stars or param.assignment_details):
                 # add a warning only if there's not another one.
                 calling_va = _get_calling_var_args(evaluator, var_args)
                 if calling_va is not None:

test/static_analysis/arguments.py

@@ -38,3 +38,20 @@ two_params(1, y=2)
 two_params(1, x=2)
 #! 17 type-error-too-many-arguments
 two_params(1, 2, y=3)
+
+# -----------------
+# default arguments
+# -----------------
+
+def default(x, y=1, z=2):
+    return x
+
+#! 7 type-error-too-few-arguments
+default()
+default(1)
+default(1, 2)
+default(1, 2, 3)
+#! 17 type-error-too-many-arguments
+default(1, 2, 3, 4)
+
+default(x=1)