Copy unittest.bzl tests from bazel_skylib to rules_testing.

Register toolchains

PiperOrigin-RevId: 699254280

Author: A Googler

WORKSPACE.bazel

@@ -101,3 +101,8 @@ pip_parse(
 load("@docs-pypi//:requirements.bzl", "install_deps")
 
 install_deps()
+
+# TODO(b/380296146): move unittest toolchain from skylib into rules_testing
+load("@bazel_skylib//lib:unittest.bzl", "register_unittest_toolchains")
+
+register_unittest_toolchains()

tests/BUILD

@@ -18,6 +18,7 @@ load("@bazel_skylib//rules:common_settings.bzl", "string_flag")
 load(":analysis_test_tests.bzl", "analysis_test_test_suite")
 load(":truth_tests.bzl", "truth_test_suite")
 load(":unit_test_tests.bzl", "unit_test_test_suite")
+load(":unittest_tests.bzl", "unittest_passing_tests_suite")
 
 licenses(["notice"])
 
@@ -47,6 +48,8 @@ truth_test_suite(name = "truth_tests")
 
 unit_test_test_suite(name = "unit_test_test_suite")
 
+unittest_passing_tests_suite()
+
 build_test(
     name = "build_tests",
     targets = [