added test

lark/lexer.py

@@ -124,7 +124,7 @@ class Token(Str):
         return (self.__class__, (self.type, self.value, self.pos_in_stream, self.line, self.column, ))
 
     def __repr__(self):
-        return 'Token(%s, %r)' % (self.type, self.value)
+        return 'Token(%r, %r)' % (self.type, self.value)
 
     def __deepcopy__(self, memo):
         return Token(self.type, self.value, self.pos_in_stream, self.line, self.column)

lark/tree.py

@@ -25,7 +25,7 @@ class Tree(object):
         return self._meta
 
     def __repr__(self):
-        return 'Tree(%s, %s)' % (self.data, self.children)
+        return 'Tree(%r, %r)' % (self.data, self.children)
 
     def _pretty_label(self):
         return self.data
@@ -172,4 +172,3 @@ def pydot__tree_to_png(tree, filename, rankdir="LR", **kwargs):
 
     _to_pydot(tree)
     graph.write_png(filename)
-

tests/test_trees.py

@@ -7,6 +7,7 @@ import pickle
 import functools
 
 from lark.tree import Tree
+from lark.lexer import Token
 from lark.visitors import Visitor, Visitor_Recursive, Transformer, Interpreter, visit_children_decor, v_args, Discard
 
 
@@ -22,6 +23,9 @@ class TestTrees(TestCase):
         data = pickle.dumps(s)
         assert pickle.loads(data) == s
 
+    def test_repr_runnable(self):
+        assert self.tree1 == eval(repr(self.tree1))
+
     def test_iter_subtrees(self):
         expected = [Tree('b', 'x'), Tree('c', 'y'), Tree('d', 'z'),
                     Tree('a', [Tree('b', 'x'), Tree('c', 'y'), Tree('d', 'z')])]
@@ -232,4 +236,3 @@ class TestTrees(TestCase):
 
 if __name__ == '__main__':
     unittest.main()
-