1 files changed, 75 insertions, 0 deletions
diff --git a/lib/mako/util.py b/lib/mako/util.py
index 0257464..83bb0cf 100644
--- a/lib/mako/util.py
+++ b/lib/mako/util.py
@@ -120,3 +120,78 @@ class LRUCache(dict):
                     # if we couldnt find a key, most likely some other thread broke in 
                     # on us. loop around and try again
                     break
+
+def restore__ast(_ast):
+    """Attempt to restore the required classes to the _ast module if it
+    appears to be missing them
+    """
+    if hasattr(_ast, 'AST'):
+        return
+    _ast.PyCF_ONLY_AST = 2 << 9
+    m = compile("""\
+def foo(): pass
+class Bar(object): pass
+if False: pass
+baz = 'mako'
+1 + 2 - 3 * 4 / 5
+6 // 7 % 8 << 9 >> 10
+11 & 12 ^ 13 | 14
+15 and 16 or 17
+-baz + (not +18) - ~17
+baz and 'foo' or 'bar'
+(mako is baz == baz) is not baz != mako
+mako > baz < mako >= baz <= mako
+mako in baz not in mako""", '<unknown>', 'exec', _ast.PyCF_ONLY_AST)
+    _ast.Module = type(m)
+
+    for cls in _ast.Module.__mro__:
+        if cls.__name__ == 'mod':
+            _ast.mod = cls
+        elif cls.__name__ == 'AST':
+            _ast.AST = cls
+
+    _ast.FunctionDef = type(m.body[0])
+    _ast.ClassDef = type(m.body[1])
+    _ast.If = type(m.body[2])
+
+    _ast.Name = type(m.body[3].targets[0])
+    _ast.Store = type(m.body[3].targets[0].ctx)
+    _ast.Str = type(m.body[3].value)
+
+    _ast.Sub = type(m.body[4].value.op)
+    _ast.Add = type(m.body[4].value.left.op)
+    _ast.Div = type(m.body[4].value.right.op)
+    _ast.Mult = type(m.body[4].value.right.left.op)
+
+    _ast.RShift = type(m.body[5].value.op)
+    _ast.LShift = type(m.body[5].value.left.op)
+    _ast.Mod = type(m.body[5].value.left.left.op)
+    _ast.FloorDiv = type(m.body[5].value.left.left.left.op)
+
+    _ast.BitOr = type(m.body[6].value.op)
+    _ast.BitXor = type(m.body[6].value.left.op)
+    _ast.BitAnd = type(m.body[6].value.left.left.op)
+
+    _ast.Or = type(m.body[7].value.op)
+    _ast.And = type(m.body[7].value.values[0].op)
+
+    _ast.Invert = type(m.body[8].value.right.op)
+    _ast.Not = type(m.body[8].value.left.right.op)
+    _ast.UAdd = type(m.body[8].value.left.right.operand.op)
+    _ast.USub = type(m.body[8].value.left.left.op)
+
+    _ast.Or = type(m.body[9].value.op)
+    _ast.And = type(m.body[9].value.values[0].op)
+
+    _ast.IsNot = type(m.body[10].value.ops[0])
+    _ast.NotEq = type(m.body[10].value.ops[1])
+    _ast.Is = type(m.body[10].value.left.ops[0])
+    _ast.Eq = type(m.body[10].value.left.ops[1])
+
+    _ast.Gt = type(m.body[11].value.ops[0])
+    _ast.Lt = type(m.body[11].value.ops[1])
+    _ast.GtE = type(m.body[11].value.ops[2])
+    _ast.LtE = type(m.body[11].value.ops[3])
+
+    _ast.In = type(m.body[12].value.ops[0])
+    _ast.NotIn = type(m.body[12].value.ops[1])