diff --git a/jedi/api/file_name.py b/jedi/api/file_name.py
index fac187f6..5c2ce3ef 100644
--- a/jedi/api/file_name.py
+++ b/jedi/api/file_name.py
@@ -57,16 +57,14 @@ def _get_string_additions(module_context, start_leaf):
     addition = start_leaf.get_previous_leaf()
     if addition != '+':
         return ''
-    return _add_strings(module_context, reversed(list(iterate_nodes())))
+    context = module_context.create_context(start_leaf)
+    return _add_strings(context, reversed(list(iterate_nodes())))
 
 
-def _add_strings(module_context, nodes, add_slash=False):
+def _add_strings(context, nodes, add_slash=False):
     string = ''
-    context = None
     first = True
     for child_node in nodes:
-        if context is None:
-            context = module_context.create_context(child_node)
         contexts = context.eval_node(child_node)
         if len(contexts) != 1:
             return None
@@ -87,18 +85,42 @@ class FileName(AbstractArbitraryName):
 
 
 def _maybe_add_os_path_join(module_context, start_leaf, string):
+    def check_for_power(join_atom, nodes):
+        context = module_context.create_context(join_atom)
+        contexts = context.eval_node(join_atom)
+        if any([c.name.get_qualified_names(include_module_names=True)
+                != ('os', 'path', 'join') for c in contexts]):
+            return string, False
+        return _add_strings(context, nodes, add_slash=True), True
+
     arglist = start_leaf.parent
-    if arglist.type == 'arglist':
+    if start_leaf.type == 'error_leaf':
+        index = arglist.children.index(start_leaf)
+        if index > 0:
+            error_node = arglist.children[index - 1]
+            if error_node.type == 'error_node' and len(error_node.children) >= 3:
+                atom = error_node.children[-3]
+                arglist = error_node.children[-1]
+                if atom.type in ('atom_expr', 'power', 'name') and arglist.type == 'arglist':
+                    return check_for_power(atom, arglist.children[::2])
+    elif arglist.type == 'arglist':
         trailer = arglist.parent
-        if trailer.type == 'trailer':
+        if trailer.type == 'error_node':
+            index = trailer.children.index(arglist)
+            assert index >= 2
+            assert trailer.children[index - 1] == '('
+            name = trailer.children[index - 2]
+            if name.type in ('atom_expr', 'power', 'name'):
+                nodes = arglist.children[:arglist.children.index(start_leaf):2]
+                return check_for_power(name, nodes)
+
+        elif False:
+            for node in reversed(trailer.children[:trailer.children.index(arglist)]):
+                print(node)
+        elif trailer.type == 'trailer':
             atom = trailer.get_previous_sibling()
             if atom.type != 'trailer':
-                context = module_context.create_context(atom)
-                contexts = context.eval_node(atom)
-                if any([c.name.get_qualified_names(include_module_names=True)
-                        != ('os', 'path', 'join') for c in contexts]):
-                    return string, False
                 nodes = arglist.children[:arglist.children.index(start_leaf):2]
-                return _add_strings(module_context, nodes, add_slash=True), True
+                return check_for_power(atom, nodes)
 
     return string, False
diff --git a/test/test_api/test_completion.py b/test/test_api/test_completion.py
index 0ff73dc2..9cc155ae 100644
--- a/test/test_api/test_completion.py
+++ b/test/test_api/test_completion.py
@@ -213,9 +213,15 @@ os_path = 'from os.path import *\n'
         (f2, os_path + 'join(dirname(__file__), "completion", "basi', None, ['c.py']),
         (f2, os_path + 'join(dirname(__file__), "completion", "basi)', 43, ['c.py']),
         (f2, os_path + 'join(dirname(__file__), "completion", "basi")', 43, ['c.py']),
-        (f2, os_path + 'join(dirname(__file__), "completion", "basi)', 35, []),
+        (f2, os_path + 'join(dirname(__file__), "completion", "basi)', 35, ['']),
         (f2, os_path + 'join(dirname(__file__), "completion", "basi)', 33, ['on']),
         (f2, os_path + 'join(dirname(__file__), "completion", "basi")', 33, ['on']),
+
+        # join with one argument
+        #(f2, os_path + 'join("tes', 10, ['t']),
+        #(f2, os_path + 'join("tes)', 10, ['t']),
+        #(f2, os_path + 'join("tes"', 10, ['t']),
+        #(f2, os_path + 'join("tes")', 10, ['t']),
     ]
 )
 def test_file_path_completions(Script, file, code, column, expected):