Test case for issue danielgtaylor#63

betterproto/tests/inputs/oneof_enum/oneof_enum-enum-0.json

@@ -0,0 +1,3 @@
+{
+  "signal": "PASS"
+}

betterproto/tests/inputs/oneof_enum/oneof_enum-enum-1.json

@@ -0,0 +1,3 @@
+{
+  "signal": "RESIGN"
+}

betterproto/tests/inputs/oneof_enum/oneof_enum.json

@@ -0,0 +1,6 @@
+{
+  "move": {
+    "x": 2,
+    "y": 3
+  }
+}

betterproto/tests/inputs/oneof_enum/oneof_enum.proto

@@ -0,0 +1,18 @@
+syntax = "proto3";
+
+message Test {
+  oneof action {
+    Signal signal = 1;
+    Move move = 2;
+  }
+}
+
+enum Signal {
+  PASS = 0;
+  RESIGN = 1;
+}
+
+message Move {
+  int32 x = 1;
+  int32 y = 2;
+}

betterproto/tests/inputs/oneof_enum/test_oneof_enum.py

@@ -0,0 +1,42 @@
+import pytest
+
+import betterproto
+from betterproto.tests.output_betterproto.oneof_enum.oneof_enum import (
+    Move,
+    Signal,
+    Test,
+)
+from betterproto.tests.util import get_test_case_json_data
+
+
+@pytest.mark.xfail
+def test_which_one_of_returns_enum_with_default_value():
+    """
+    returns first field when it is enum and set with default value
+    """
+    message = Test()
+    message.from_json(get_test_case_json_data("oneof_enum", "oneof_enum-enum-0.json"))
+    assert message.move is None
+    assert message.signal == Signal.PASS
+    assert betterproto.which_one_of(message, "action") == ("signal", Signal.PASS)
+
+
+@pytest.mark.xfail
+def test_which_one_of_returns_enum_with_non_default_value():
+    """
+    returns first field when it is enum and set with non default value
+    """
+    message = Test()
+    message.from_json(get_test_case_json_data("oneof_enum", "oneof_enum-enum-1.json"))
+    assert message.move is None
+    assert message.signal == Signal.PASS
+    assert betterproto.which_one_of(message, "action") == ("signal", Signal.RESIGN)
+
+
+@pytest.mark.xfail
+def test_which_one_of_returns_second_field_when_set():
+    message = Test()
+    message.from_json(get_test_case_json_data("oneof_enum"))
+    assert message.move == Move(x=2, y=3)
+    assert message.signal == 0
+    assert betterproto.which_one_of(message, "action") == ("move", Move(x=2, y=3))