diff options
Diffstat (limited to 'ext/pybind11/tests/test_alias_initialization.py')
-rw-r--r-- | ext/pybind11/tests/test_alias_initialization.py | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/ext/pybind11/tests/test_alias_initialization.py b/ext/pybind11/tests/test_alias_initialization.py new file mode 100644 index 000000000..0ed9d2f79 --- /dev/null +++ b/ext/pybind11/tests/test_alias_initialization.py @@ -0,0 +1,79 @@ +import gc + + +def test_alias_delay_initialization1(capture): + """A only initializes its trampoline class when we inherit from it; if we just + create and use an A instance directly, the trampoline initialization is bypassed + and we only initialize an A() instead (for performance reasons). + """ + from pybind11_tests import A, call_f + + class B(A): + def __init__(self): + super(B, self).__init__() + + def f(self): + print("In python f()") + + # C++ version + with capture: + a = A() + call_f(a) + del a + gc.collect() + assert capture == "A.f()" + + # Python version + with capture: + b = B() + call_f(b) + del b + gc.collect() + assert capture == """ + PyA.PyA() + PyA.f() + In python f() + PyA.~PyA() + """ + + +def test_alias_delay_initialization2(capture): + """A2, unlike the above, is configured to always initialize the alias; while + the extra initialization and extra class layer has small virtual dispatch + performance penalty, it also allows us to do more things with the trampoline + class such as defining local variables and performing construction/destruction. + """ + from pybind11_tests import A2, call_f + + class B2(A2): + def __init__(self): + super(B2, self).__init__() + + def f(self): + print("In python B2.f()") + + # No python subclass version + with capture: + a2 = A2() + call_f(a2) + del a2 + gc.collect() + assert capture == """ + PyA2.PyA2() + PyA2.f() + A2.f() + PyA2.~PyA2() + """ + + # Python subclass version + with capture: + b2 = B2() + call_f(b2) + del b2 + gc.collect() + assert capture == """ + PyA2.PyA2() + PyA2.f() + In python B2.f() + PyA2.~PyA2() + """ |