Fix bytes issue with file path adding

jedi/api/file_name.py

@@ -1,6 +1,6 @@
 import os
 
-from jedi._compatibility import FileNotFoundError
+from jedi._compatibility import FileNotFoundError, force_unicode
 from jedi.evaluate.names import AbstractArbitraryName
 from jedi.api import classes
 from jedi.evaluate.helpers import get_str_or_none
@@ -54,7 +54,7 @@ def _get_string_additions(module_context, start_leaf):
             s = get_str_or_none(c)
             if s is None:
                 return string
-            string = s + string
+            string = force_unicode(s) + string
             continue
 
         if child_node != '+':

jedi/evaluate/context/module.py

@@ -27,8 +27,9 @@ class _ModuleAttributeName(AbstractNameDefinition):
     def infer(self):
         if self._string_value is not None:
             s = self._string_value
-            if self.parent_context.evaluator.environment.version_info.major == 2:
-                s = bytes(s)
+            if self.parent_context.evaluator.environment.version_info.major == 2 \
+                    and not isinstance(s, bytes):
+                s = bytes(s, 'utf-8')
             return ContextSet([
                 create_simple_object(self.parent_context.evaluator, s)
             ])

test/test_api/test_completion.py

@@ -195,6 +195,9 @@ def test_keyword_completion(Script, code, has_keywords):
         ('example.py', 'x = f("te" + "st"', 16, [s]),
         ('example.py', 'x = f("te" + "st")', 16, [s]),
         ('example.py', 'x = f("t" + "est")', 16, [s]),
+        # This is actually not correct, but for now leave it here, because of
+        # Python 2.
+        ('example.py', 'x = f(b"t" + "est")', 17, [s]),
         ('example.py', '"test" + "', None, [s]),
     ]
 )

test/test_evaluate/test_context.py

@@ -1,3 +1,6 @@
+from jedi._compatibility import force_unicode
+
+
 def test_module_attributes(Script):
     def_, = Script('__name__').completions()
     assert def_.name == '__name__'
@@ -10,9 +13,9 @@ def test_module_attributes(Script):
 def test_module__file__(Script, environment):
     assert not Script('__file__').goto_definitions()
     def_, = Script('__file__', path='example.py').goto_definitions()
-    value = def_._name._context.get_safe_value()
+    value = force_unicode(def_._name._context.get_safe_value())
     assert value.endswith('example.py')
 
     def_, = Script('import antigravity; antigravity.__file__').goto_definitions()
-    value = def_._name._context.get_safe_value()
+    value = force_unicode(def_._name._context.get_safe_value())
     assert value.endswith('.py')