Fix a wrong branch check, fixes #1128

jedi/evaluate/flow_analysis.py

@@ -60,6 +60,7 @@ def reachability_check(context, context_scope, node, origin_scope=None):
                     if not branch_matches and origin_keyword == 'else' \
                             and node_keyword == 'except':
                         return UNREACHABLE
+                if branch_matches:
                     break
 
         # Direct parents get resolved, we filter scopes that are separate

test/completion/flow_analysis.py

@@ -29,6 +29,10 @@ finally:
     x
     x = tuple
 
+if False:
+    with open("") as defined_in_false:
+        #? ['seekable']
+        defined_in_false.seekab
 
 # -----------------
 # Return checks