Fix double wrap by NTNDArray

p4pillon/server/raw.py

@@ -5,6 +5,7 @@
 import logging
 from abc import ABC
 
+from p4p._p4p import SharedPV as _RawSharedPV
 from p4p.server.raw import SharedPV as _SharedPV
 
 _log = logging.getLogger(__name__)
@@ -154,7 +155,9 @@ def open(self, value, nt=None, wrap=None, unwrap=None, **kwargs):
         else:
             open_fn(V)
 
-        _SharedPV.open(self, V)
+        # Call the C-extension base directly, bypassing p4p.server.raw.SharedPV.open(),
+        # which would wrap() V a second time (V is already wrapped above).
+        _RawSharedPV.open(self, V)
 
     def post(self, value, **kwargs):
         """Provide an update to the Value of this PV.
@@ -180,7 +183,9 @@ def post(self, value, **kwargs):
         else:
             post_fn(self, V)
 
-        _SharedPV.post(self, V)
+        # Call the C-extension base directly, bypassing p4p.server.raw.SharedPV.post(),
+        # which would wrap() V a second time (V is already wrapped above).
+        _RawSharedPV.post(self, V)
 
     def close(self, destroy=False):
         """Close PV, disconnecting any clients.

tests/unit/server/test_sharedpv_asyncio.py

@@ -1,4 +1,5 @@
-from p4p.nt import NTScalar
+import numpy
+from p4p.nt import NTNDArray, NTScalar
 
 from p4pillon.server.asyncio import Handler, SharedPV
 
@@ -51,3 +52,22 @@ def teardown_method(self, _method):
         self.pv.close()
         del self.handler
         del self.pv
+
+
+class TestNoDoubleWrapOfInitialValue:
+    """Regression tests for `SharedPV.open()`/`.post()` each wrapping `value`
+    via `nt.wrap()` themselves before delegating to p4p's own (already
+    wrapping) `SharedPV.open()`/`.post()`, which wraps a second time. Harmless
+    for `NTScalar`, whose `wrap()` tolerates being fed an already-wrapped
+    `Value` -- but `NTNDArray.wrap()` assumes a raw `numpy.ndarray` and raises
+    when handed a `Value` on the second pass.
+    """
+
+    def test_open_with_ntndarray_does_not_double_wrap(self):
+        pv = SharedPV(nt=NTNDArray(), initial=numpy.zeros((4, 4)))
+        assert numpy.array_equal(numpy.asarray(pv.current()).flatten(), numpy.zeros(16))
+
+    def test_post_with_ntndarray_does_not_double_wrap(self):
+        pv = SharedPV(nt=NTNDArray(), initial=numpy.zeros((4, 4)))
+        pv.post(numpy.ones((4, 4)))
+        assert numpy.array_equal(numpy.asarray(pv.current()).flatten(), numpy.ones(16))

tests/unit/server/test_sharedpv_thread.py

@@ -1,4 +1,5 @@
-from p4p.nt import NTScalar
+import numpy
+from p4p.nt import NTNDArray, NTScalar
 
 from p4pillon.server.thread import Handler, SharedPV
 
@@ -51,3 +52,22 @@ def teardown_method(self, _method):
         self.pv.close()
         del self.handler
         del self.pv
+
+
+class TestNoDoubleWrapOfInitialValue:
+    """Regression tests for `SharedPV.open()`/`.post()` each wrapping `value`
+    via `nt.wrap()` themselves before delegating to p4p's own (already
+    wrapping) `SharedPV.open()`/`.post()`, which wraps a second time. Harmless
+    for `NTScalar`, whose `wrap()` tolerates being fed an already-wrapped
+    `Value` -- but `NTNDArray.wrap()` assumes a raw `numpy.ndarray` and raises
+    when handed a `Value` on the second pass.
+    """
+
+    def test_open_with_ntndarray_does_not_double_wrap(self):
+        pv = SharedPV(nt=NTNDArray(), initial=numpy.zeros((4, 4)))
+        assert numpy.array_equal(numpy.asarray(pv.current()).flatten(), numpy.zeros(16))
+
+    def test_post_with_ntndarray_does_not_double_wrap(self):
+        pv = SharedPV(nt=NTNDArray(), initial=numpy.zeros((4, 4)))
+        pv.post(numpy.ones((4, 4)))
+        assert numpy.array_equal(numpy.asarray(pv.current()).flatten(), numpy.ones(16))