Document the need to enter the virtual environment shell (#868)

[etc/vim.git] / blib2to3 / pygram.py

diff --git a/blib2to3/pygram.py b/blib2to3/pygram.py
index 919624eb3997069adcce385315322d67e2844061..f6ef00154e13c2fedae946310d9f73e6e576be0f 100644 (file)
--- a/blib2to3/pygram.py
+++ b/blib2to3/pygram.py
@@ -29,12 +29,36 @@ class Symbols(object):
             setattr(self, name, symbol)
 
 
-python_grammar = driver.load_packaged_grammar("lib2to3", _GRAMMAR_FILE)
+def initialize(cache_dir=None):
+    global python_grammar
+    global python_grammar_no_print_statement
+    global python_grammar_no_print_statement_no_exec_statement
+    global python_grammar_no_print_statement_no_exec_statement_async_keywords
+    global python_symbols
+    global pattern_grammar
+    global pattern_symbols
 
-python_symbols = Symbols(python_grammar)
+    # Python 2
+    python_grammar = driver.load_packaged_grammar("blib2to3", _GRAMMAR_FILE,
+                                                  cache_dir)
 
-python_grammar_no_print_statement = python_grammar.copy()
-del python_grammar_no_print_statement.keywords["print"]
+    python_symbols = Symbols(python_grammar)
 
-pattern_grammar = driver.load_packaged_grammar("lib2to3", _PATTERN_GRAMMAR_FILE)
-pattern_symbols = Symbols(pattern_grammar)
+    # Python 2 + from __future__ import print_function
+    python_grammar_no_print_statement = python_grammar.copy()
+    del python_grammar_no_print_statement.keywords["print"]
+
+    # Python 3.0-3.6
+    python_grammar_no_print_statement_no_exec_statement = python_grammar.copy()
+    del python_grammar_no_print_statement_no_exec_statement.keywords["print"]
+    del python_grammar_no_print_statement_no_exec_statement.keywords["exec"]
+
+    # Python 3.7+
+    python_grammar_no_print_statement_no_exec_statement_async_keywords = (
+        python_grammar_no_print_statement_no_exec_statement.copy()
+    )
+    python_grammar_no_print_statement_no_exec_statement_async_keywords.async_keywords = True
+
+    pattern_grammar = driver.load_packaged_grammar("blib2to3", _PATTERN_GRAMMAR_FILE,
+                                                   cache_dir)
+    pattern_symbols = Symbols(pattern_grammar)