[4.0.x] Fixed #33333 -- Fixed setUpTestData() crash with models.BinaryField on PostgreSQL.

This makes models.BinaryField pickleable on PostgreSQL.

Regression in 3cf80d3fcf7446afdde16a2be515c423f720e54d.

Thanks Adam Zimmerman for the report.

Backport of 2c7846d992ca512d36a73f518205015c88ed088c from main.

1 files changed, 13 insertions, 0 deletions

diff --git a/django/db/models/base.py b/django/db/models/base.py
index 3c46afcf9f..218782c8df 100644
--- a/django/db/models/base.py
+++ b/django/db/models/base.py
@@ -553,6 +553,16 @@ class Model(metaclass=ModelBase):
         state = self.__dict__.copy()
         state['_state'] = copy.copy(state['_state'])
         state['_state'].fields_cache = state['_state'].fields_cache.copy()
+        # memoryview cannot be pickled, so cast it to bytes and store
+        # separately.
+        _memoryview_attrs = []
+        for attr, value in state.items():
+            if isinstance(value, memoryview):
+                _memoryview_attrs.append((attr, bytes(value)))
+        if _memoryview_attrs:
+            state['_memoryview_attrs'] = _memoryview_attrs
+            for attr, value in _memoryview_attrs:
+                state.pop(attr)
         return state
 
     def __setstate__(self, state):
@@ -572,6 +582,9 @@ class Model(metaclass=ModelBase):
                 RuntimeWarning,
                 stacklevel=2,
             )
+        if '_memoryview_attrs' in state:
+            for attr, value in state.pop('_memoryview_attrs'):
+                state[attr] = memoryview(value)
         self.__dict__.update(state)
 
     def _get_pk_val(self, meta=None):