Fix assertion failure for unions (#1685) (#1709)
In def_readonly and def_readwrite, there is an assertion that the member comes
from the class or a base class:
static_assert(std::is_base_of<C, type>::value, "...");
However, if C and type are the same type, is_base_of will still only be true
if they are the same _non-union_ type. This means we can't define accessors
for the members of a union type because of this assertion.
Update the assertion to test
std::is_same<C, type>::value || std::is_base_of<C, type>::value
which will allow union types, or members of base classes.
Also add a basic unit test for accessing unions.diff --git a/tests/test_union.py b/tests/test_union.py
new file mode 100644
index 0000000..e1866e7
--- /dev/null
+++ b/tests/test_union.py
@@ -0,0 +1,8 @@
+from pybind11_tests import union_ as m
+
+
+def test_union():
+ instance = m.TestUnion()
+
+ instance.as_uint = 10
+ assert instance.as_int == 10