add test for new Stream.end_stream exception behaviour

Author: Kriechi

CHANGELOG.rst

@@ -8,10 +8,10 @@ dev
 
 - Support for Python 3.9 has been removed.
 - Support for PyPy 3.9 has been removed.
+- `Stream.end_stream()` now raises `NoSuchStreamError` or `StreamClosedError` exceptions, instead of a generic `KeyError`.
 - **backfill from v4.3.0** Convert emitted events into Python `dataclass`, which introduces new constructors with required arguments.
   Instantiating these events without arguments, as previously commonly used API pattern, will no longer work.
 
-
 **API Changes (Backward Compatible)**
 
 - Support for Python 3.14 has been added.

tests/test_basic_logic.py

@@ -340,6 +340,23 @@ def test_end_stream_without_data(self, frame_factory) -> None:
         assert not events
         assert c.data_to_send() == f.serialize()
 
+    def test_end_stream_exceptions(self, frame_factory) -> None:
+        c = h2.connection.H2Connection()
+        c.initiate_connection()
+        c.send_headers(1, self.example_request_headers, end_stream=False)
+        c.clear_outbound_data_buffer()
+
+        with pytest.raises(h2.exceptions.NoSuchStreamError):
+            c.end_stream(42)
+
+        c.end_stream(1)
+
+        c.send_headers(5, self.example_request_headers, end_stream=False)
+
+        with pytest.raises(h2.exceptions.StreamClosedError):
+            c.end_stream(3)
+
+
     def test_cannot_send_headers_on_lower_stream_id(self) -> None:
         """
         Once stream ID x has been used, cannot use stream ID y where y < x.