text: # Copyright 2019 Google LLC
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     https://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  
  import collections
  
  from absl.testing import absltest
  from absl.testing import parameterized
  
  from jax import test_util as jtu
  from jax import tree_util
  
  
  def _dummy_func(*args, **kwargs):
    return
  
  
  ATuple = collections.namedtuple("ATuple", ("foo", "bar"))
  
  class ANamedTupleSubclass(ATuple):
    pass
  
  class AnObject(object):
  
    def __init__(self, x, y, z):
      self.x = x
      self.y = y
      self.z = z
  
    def __eq__(self, other):
      return self.x == other.x and self.y == other.y and self.z == other.z
  
    def __hash__(self):
      return hash((self.x, self.y, self.z))
  
    def __repr__(self):
      return "AnObject({},{},{})".format(self.x, self.y, self.z)
  
  
  tree_util.register_pytree_node(AnObject, lambda o: ((o.x, o.y), o.z),
                                 lambda z, xy: AnObject(xy[0], xy[1], z))
  
  PYTREES = [
      ("foo",),
      ((),),
      (([()]),),
      ((1, 2),),
      (((1, "foo"), ["bar", (3, None, 7)]),),
      ([3],),
      ([3, ATuple(foo=(3, ATuple(foo=3, bar=None)), bar={"baz": 34})],),
      ([AnObject(3, None, [4, "foo"])],),
      ({"a": 1, "b": 2},),
      (collections.OrderedDict([("foo", 34), ("baz", 101), ("something", -42)]),),
      (ANamedTupleSubclass(foo="hello", bar=3.5),),
  ]
  
  
  class TreeTest(jtu.JaxTestCase):
  
    @parameterized.parameters(*PYTREES)
    def testRoundtrip(self, inputs):
      xs, tree = tree_util.tree_flatten(inputs)
      actual = tree_util.tree_unflatten(tree, xs)
      self.assertEqual(actual, inputs)
  
    @parameterized.parameters(*PYTREES)
    def testRoundtripWithFlattenUpTo(self, inputs):
      _, tree = tree_util.tree_flatten(inputs)
      if not hasattr(tree, "flatten_up_to"):
        self.skipTest("Test requires Jaxlib >= 0.1.23")
      xs = tree.flatten_up_to(inputs)
      actual = tree_util.tree_unflatten(tree, xs)
      self.assertEqual(actual, inputs)
  
    @parameterized.parameters(
        (tree_util.Partial(_dummy_func),),
        (tree_util.Partial(_dummy_func, 1, 2),),
        (tree_util.Partial(_dummy_func, x="a"),),
        (tree_util.Partial(_dummy_func, 1, 2, 3, x=4, y=5),),
    )
    def testRoundtripPartial(self, inputs):
      xs, tree = tree_util.tree_flatten(inputs)
      actual = tree_util.tree_unflatten(tree, xs)
      # functools.partial does not support equality comparisons:
      # https://stackoverflow.com/a/32786109/809705
      self.assertEqual(actual.func, inputs.func)
      self.assertEqual(actual.args, inputs.args)
      self.assertEqual(actual.keywords, inputs.keywords)
  
    @parameterized.parameters(*PYTREES)
    def testRoundtripViaBuild(self, inputs):
      xs, tree = tree_util.process_pytree(tuple, inputs)
      actual = tree_util.build_tree(tree, xs)
      self.assertEqual(actual, inputs)
  
    def testChildren(self):
      _, tree = tree_util.tree_flatten(((1, 2, 3), (4,)))
      _, c0 = tree_util.tree_flatten((0, 0, 0))
      _, c1 = tree_util.tree_flatten((7,))
      if not callable(tree.children):
        self.skipTest("Test requires Jaxlib >= 0.1.23")
      self.assertEqual([c0, c1], tree.children())
  
    def testFlattenUpTo(self):
      _, tree = tree_util.tree_flatten([(1, 2), None, ATuple(foo=3, bar=7)])
      if not hasattr(tree, "flatten_up_to"):
        self.skipTest("Test requires Jaxlib >= 0.1.23")
      out = tree.flatten_up_to([({
          "foo": 7
      }, (3, 4)), None, ATuple(foo=(11, 9), bar=None)])
      self.assertEqual(out, [{"foo": 7}, (3, 4), (11, 9), None])
  
    def testTreeMultimap(self):
      x = ((1, 2), (3, 4, 5))
      y = (([3], None), ({"foo": "bar"}, 7, [5, 6]))
      out = tree_util.tree_multimap(lambda *xs: tuple(xs), x, y)
      self.assertEqual(out, (((1, [3]), (2, None)),
                             ((3, {"foo": "bar"}), (4, 7), (5, [5, 6]))))
  
  
  if __name__ == "__main__":
    absltest.main()
  