Move some more stuff to a python directory in the parser.

jedi/parser/python/__init__.py

@@ -0,0 +1,43 @@
+import os
+
+from jedi._compatibility import FileNotFoundError
+from jedi.parser.pgen2.pgen import generate_grammar
+from jedi.parser.parser import Parser, ParserWithRecovery
+from jedi.parser.tokenize import source_tokens
+
+
+_loaded_grammars = {}
+
+
+def load_grammar(version='3.6'):
+    # For now we only support two different Python syntax versions: The latest
+    # Python 3 and Python 2. This may change.
+    if version in ('3.2', '3.3'):
+        version = '3.4'
+    elif version == '2.6':
+        version = '2.7'
+
+    file = 'grammar' + version + '.txt'
+
+    global _loaded_grammars
+    path = os.path.join(os.path.dirname(__file__), file)
+    try:
+        return _loaded_grammars[path]
+    except KeyError:
+        try:
+            return _loaded_grammars.setdefault(path, generate_grammar(path))
+        except FileNotFoundError:
+            # Just load the default if the file does not exist.
+            return load_grammar()
+
+
+def parse(source, grammar=None, error_recovery=False):
+    if grammar is None:
+        grammar = load_grammar()
+
+    tokens = source_tokens(source)
+    if error_recovery:
+        parser = ParserWithRecovery
+    else:
+        parser = Parser
+    parser(grammar, tokens)