create jax.extend.random as a copy of jax.prng

Co-authored-by: Jake Vanderplas <jakevdp@google.com>
PiperOrigin-RevId: 559874051

jax/BUILD

@@ -17,6 +17,7 @@
 load("@bazel_skylib//rules:common_settings.bzl", "bool_flag")
 load(
     "//jaxlib:jax.bzl",
+    "jax_extend_internal_users",
     "jax_extra_deps",
     "jax_internal_packages",
     "jax_test_util_visibility",
@@ -63,6 +64,15 @@ package_group(
     ] + jax_internal_packages,
 )
 
+package_group(
+    name = "jax_extend_users",
+    packages = [
+        # Intentionally avoid jax dependencies on jax.extend.
+        # See https://jax.readthedocs.io/en/latest/jep/15856-jex.html
+        "//third_party/py/jax/tests/...",
+    ] + jax_extend_internal_users,
+)
+
 package_group(
     name = "mosaic_users",
     packages = [
@@ -872,6 +882,13 @@ pytype_library(
     ],
 )
 
+pytype_library(
+    name = "extend",
+    srcs = glob(["extend/**/*.py"]),
+    visibility = [":jax_extend_users"],
+    deps = [":jax"],
+)
+
 pytype_library(
     name = "mosaic",
     srcs = [

jax/extend/__init__.py

@@ -27,3 +27,7 @@ this package offers **no compatibility guarantee** across releases.
 Breaking changes will be announced via the
 `JAX project changelog <https://jax.readthedocs.io/en/latest/changelog.html>`_.
 """
+
+from jax.extend import (
+    random as random,
+)

jax/extend/random.py

@@ -0,0 +1,26 @@
+# Copyright 2023 The JAX Authors.
+#
+# 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.
+
+# Note: import <name> as <name> is required for names to be exported.
+# See PEP 484 & https://github.com/google/jax/issues/7570
+
+from jax._src.prng import (
+  PRNGImpl as PRNGImpl,
+  seed_with_impl as seed_with_impl,
+  threefry2x32_p as threefry2x32_p,
+  threefry_2x32 as threefry_2x32,
+  threefry_prng_impl as threefry_prng_impl,
+  rbg_prng_impl as rbg_prng_impl,
+  unsafe_rbg_prng_impl as unsafe_rbg_prng_impl,
+)

jaxlib/jax.bzl

@@ -36,6 +36,7 @@ tf_exec_properties = _tf_exec_properties
 tf_cuda_tests_tags = _tf_cuda_tests_tags
 
 jax_internal_packages = []
+jax_extend_internal_users = []
 mosaic_internal_users = []
 pallas_gpu_internal_users = []
 pallas_tpu_internal_users = []

setup.cfg

@@ -34,6 +34,7 @@ per-file-ignores =
   jax/dlpack.py:F401
   jax/dtypes.py:F401
   jax/errors.py:F401
+  jax/extend/*.py:F401
   jax/flatten_util.py:F401
   jax/interpreters/ad.py:F401
   jax/interpreters/batching.py:F401

tests/BUILD

@@ -109,6 +109,12 @@ jax_test(
     ],
 )
 
+jax_test(
+    name = "extend_test",
+    srcs = ["extend_test.py"],
+    deps = ["//jax:extend"],
+)
+
 jax_test(
     name = "fft_test",
     srcs = ["fft_test.py"],

tests/extend_test.py

@@ -0,0 +1,37 @@
+# Copyright 2023 The JAX Authors.
+#
+# 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 absl.testing import absltest
+
+import jax.extend as jex
+
+from jax._src import prng
+from jax._src import test_util as jtu
+
+from jax import config
+config.parse_flags_with_absl()
+
+class ExtendTest(jtu.JaxTestCase):
+  def test_symbols(self):
+    # Assume these are tested in random_test.py, only check equivalence
+    self.assertIs(jex.random.PRNGImpl, prng.PRNGImpl)
+    self.assertIs(jex.random.seed_with_impl, prng.seed_with_impl)
+    self.assertIs(jex.random.threefry2x32_p, prng.threefry2x32_p)
+    self.assertIs(jex.random.threefry_2x32, prng.threefry_2x32)
+    self.assertIs(jex.random.threefry_prng_impl, prng.threefry_prng_impl)
+    self.assertIs(jex.random.rbg_prng_impl, prng.rbg_prng_impl)
+    self.assertIs(jex.random.unsafe_rbg_prng_impl, prng.unsafe_rbg_prng_impl)
+
+if __name__ == "__main__":
+  absltest.main(testLoader=jtu.JaxTestLoader())