Add the grammar as an argument to saving the parser.

This makes collisions of different grammars when loading from the cache impossible.

jedi/parser/pgen2/grammar.py

@@ -16,8 +16,9 @@ fallback token code OP, but the parser needs the actual token code.
 
 """
 
-# Python imports
 import pickle
+import hashlib
+
 
 
 class Grammar(object):
@@ -74,7 +75,7 @@ class Grammar(object):
 
     """
 
-    def __init__(self):
+    def __init__(self, bnf_text):
         self.symbol2number = {}
         self.number2symbol = {}
         self.states = []
@@ -84,6 +85,7 @@ class Grammar(object):
         self.tokens = {}
         self.symbol2label = {}
         self.start = 256
+        self.sha256 = hashlib.sha256(bnf_text.encode("utf-8")).hexdigest()
 
     def dump(self, filename):
         """Dump the grammar tables to a pickle file."""