The fast parser had some splitting issues.

jedi/parser/fast.py

@@ -353,6 +353,9 @@ class FastParser(use_metaclass(CachedFastParser)):
                         - l.count(')') - l.count(']') - l.count('}')))
 
             current_lines.append(l)
+
+        if previous_line is not None:
+            current_lines.append(previous_line)
         if current_lines:
             yield gen_part()
 

test/test_parser/test_fast_parser.py

@@ -75,6 +75,9 @@ def test_split_parts():
     test('a\n\n', 'def b(): pass\n', 'c\n')
     test('a\n', 'def b():\n pass\n', 'c\n')
 
+    test('from x\\\n')
+    test('a\n\\\n')
+
 
 def check_fp(src, number_parsers_used, number_of_splits=None, number_of_misses=0):
     if number_of_splits is None: