Workaround the issues with hypothesis 6.6

Hypothesis 6.6 will produce:

    E  hypothesis.errors.FailedHealthCheck: test/test_flow_control_window.py::TestAutomaticFlowControl::test_mixing_update_forms uses the 'frame_factory' fixture, which is reset between function calls but not between test cases generated by `@given(...)`.  You can change it to a module- or session-scoped fixture if it is safe to reuse; if not we recommend using a context manager inside your test function.  See https://docs.pytest.org/en/latest/fixture.html#sharing-test-data for details on fixture scope.
    E  See https://hypothesis.readthedocs.io/en/latest/healthchecks.html for more information about this. If you want to disable just this health check, add HealthCheck.function_scoped_fixture to the suppress_health_check settings for this test.

Since the tests already workaround the problem,
acknowledging HypothesisWorks/hypothesis#377,
we can safely disable the check.

Hypothesis 5.49 introduced the function_scoped_fixture health check value,
hence it is now the lowest required version of hypothesis.

Author: hroncok

test/test_basic_logic.py

@@ -21,7 +21,7 @@
 
 from . import helpers
 
-from hypothesis import given
+from hypothesis import given, settings, HealthCheck
 from hypothesis.strategies import integers
 
 
@@ -790,6 +790,7 @@ def test_headers_are_lowercase(self, frame_factory):
         assert c.data_to_send() == expected_frame.serialize()
 
     @given(frame_size=integers(min_value=2**14, max_value=(2**24 - 1)))
+    @settings(suppress_health_check=[HealthCheck.function_scoped_fixture])
     def test_changing_max_frame_size(self, frame_factory, frame_size):
         """
         When the user changes the max frame size and the change is ACKed, the

test/test_flow_control_window.py

@@ -7,7 +7,7 @@
 """
 import pytest
 
-from hypothesis import given
+from hypothesis import given, settings, HealthCheck
 from hypothesis.strategies import integers
 
 import h2.config
@@ -715,6 +715,7 @@ def _setup_connection_and_send_headers(self, frame_factory):
         return c
 
     @given(stream_id=integers(max_value=0))
+    @settings(suppress_health_check=[HealthCheck.function_scoped_fixture])
     def test_must_acknowledge_for_stream(self, frame_factory, stream_id):
         """
         Flow control acknowledgements must be done on a stream ID that is
@@ -740,6 +741,7 @@ def test_must_acknowledge_for_stream(self, frame_factory, stream_id):
             )
 
     @given(size=integers(max_value=-1))
+    @settings(suppress_health_check=[HealthCheck.function_scoped_fixture])
     def test_cannot_acknowledge_less_than_zero(self, frame_factory, size):
         """
         The user must acknowledge at least 0 bytes.
@@ -837,6 +839,7 @@ def test_acknowledging_streams_we_never_saw(self, frame_factory):
             c.acknowledge_received_data(2048, stream_id=101)
 
     @given(integers(min_value=1025, max_value=DEFAULT_FLOW_WINDOW))
+    @settings(suppress_health_check=[HealthCheck.function_scoped_fixture])
     def test_acknowledging_1024_bytes_when_empty_increments(self,
                                                             frame_factory,
                                                             increment):
@@ -873,6 +876,7 @@ def test_acknowledging_1024_bytes_when_empty_increments(self,
     # This test needs to use a lower cap, because otherwise the algo will
     # increment the stream window anyway.
     @given(integers(min_value=1025, max_value=(DEFAULT_FLOW_WINDOW // 4) - 1))
+    @settings(suppress_health_check=[HealthCheck.function_scoped_fixture])
     def test_connection_only_empty(self, frame_factory, increment):
         """
         If the connection flow control window is empty, but the stream flow
@@ -916,6 +920,7 @@ def test_connection_only_empty(self, frame_factory, increment):
         assert c.data_to_send() == expected_data
 
     @given(integers(min_value=1025, max_value=DEFAULT_FLOW_WINDOW))
+    @settings(suppress_health_check=[HealthCheck.function_scoped_fixture])
     def test_mixing_update_forms(self, frame_factory, increment):
         """
         If the user mixes ackowledging data with manually incrementing windows,

tox.ini

@@ -15,7 +15,7 @@ deps =
     pytest==6.0.2
     pytest-cov==2.10.1
     pytest-xdist==2.1.0
-    hypothesis>=5.5,<6
+    hypothesis>=5.49,<7
 commands =
     pytest --cov-report=xml  --cov-report=term --cov=h2 {posargs}