Add a test for Updater.current_version.

We don't have any tests that actually cover a protobuf involved thing
yet. This one's trivial, but shows how to do it.

Bug: None
Test: atest --host-unit-test-only
Change-Id: I6eb6ccd43663ec77af6ee38298b759a7f4eab8ac

2 files changed, 73 insertions, 0 deletions

diff --git a/Android.bp b/Android.bp
index b720fa3..fe7aaf5 100644
--- a/Android.bp
+++ b/Android.bp
@@ -138,6 +138,23 @@ python_test_host {
     },
 }
 
+// This test is intentionally not in the tests/ directory. Everything in the
+// tests/ directory should be runnable with pytest, and this file is not because
+// it depends on the generated protobuf modules.
+python_test_host {
+    name: "external_updater_base_updater_test",
+    defaults: ["external_updater_test_defaults"],
+    main: "test_base_updater.py",
+    srcs: ["test_base_updater.py"],
+    libs: [
+        "external_updater_lib",
+        "external_updater_test_lib",
+    ],
+    test_options: {
+        unit_test: true,
+    },
+}
+
 // The tests in tests/endtoend are not built as a Soong module because we can't
 // run those tests via python_test_host. It's an end-to-end test so it needs to
 // run `repo`, but `repo init` will try to clone the real repo source (the thing
diff --git a/test_base_updater.py b/test_base_updater.py
new file mode 100644
index 0000000..e930a35
--- /dev/null
+++ b/test_base_updater.py
@@ -0,0 +1,56 @@
+#
+# Copyright (C) 2024 The Android Open Source Project
+#
+# 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
+#
+#      http://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.
+#
+"""Unit tests for base_updater."""
+
+import unittest
+from pathlib import Path
+
+import base_updater
+# pylint: disable=import-error
+import metadata_pb2  # type: ignore
+# pylint: enable=import-error
+
+
+class UpdaterTest(unittest.TestCase):
+    """Unit tests for Updater."""
+
+    def test_current_version(self) -> None:
+        """Tests that Updater.current_version returns the appropriate value."""
+        updater = base_updater.Updater(
+            # This is absolute so we get the fast path out of the path canonicalization
+            # that would otherwise require us to define ANDROID_BUILD_TOP or run from a
+            # temp repo tree.
+            Path("/"),
+            metadata_pb2.Identifier(),
+            "old version",
+        )
+        self.assertEqual(updater.current_version, "old version")
+
+        identifier = metadata_pb2.Identifier()
+        identifier.version = "old version"
+        updater = base_updater.Updater(
+            # This is absolute so we get the fast path out of the path canonicalization
+            # that would otherwise require us to define ANDROID_BUILD_TOP or run from a
+            # temp repo tree.
+            Path("/"),
+            identifier,
+            "",
+        )
+        self.assertEqual(updater.current_version, "old version")
+
+
+if __name__ == "__main__":
+    unittest.main(verbosity=2)