bt2: prepend underscore to exceptions not meant to be raised by user

[babeltrace.git] / src / bindings / python / bt2 / bt2 / stream.py

diff --git a/src/bindings/python/bt2/bt2/stream.py b/src/bindings/python/bt2/bt2/stream.py
index 5accfcd0751cfdf271121587b1b6b0d8c73a1ab1..2d966509fa4a251b8cf5a8fce8da34741e0c9ed2 100644 (file)
--- a/src/bindings/python/bt2/bt2/stream.py
+++ b/src/bindings/python/bt2/bt2/stream.py
@@ -34,7 +34,9 @@ class _Stream(bt2.object._SharedObject):
     def cls(self):
         stream_class_ptr = native_bt.stream_borrow_class(self._ptr)
         assert stream_class_ptr is not None
-        return bt2.stream_class._StreamClass._create_from_ptr_and_get_ref(stream_class_ptr)
+        return bt2.stream_class._StreamClass._create_from_ptr_and_get_ref(
+            stream_class_ptr
+        )
 
     @property
     def name(self):
@@ -52,9 +54,14 @@ class _Stream(bt2.object._SharedObject):
         return id if id >= 0 else None
 
     def create_packet(self):
+        if not self.cls.supports_packets:
+            raise ValueError(
+                'cannot create packet: stream class does not support packets'
+            )
+
         packet_ptr = native_bt.packet_create(self._ptr)
 
         if packet_ptr is None:
-            raise bt2.CreationError('cannot create packet object')
+            raise bt2._MemoryError('cannot create packet object')
 
         return bt2.packet._Packet._create_from_ptr(packet_ptr)