Refactor test_matplotlib_inline_on_import to see if can fix test for macos.

Author: fleming79

tests/conftest.py

@@ -31,6 +31,7 @@
 @pytest.hookimpl
 def pytest_configure(config):
     os.environ["PYTEST_TIMEOUT"] = str(1e6) if async_kernel.utils.LAUNCHED_BY_DEBUGPY else str(utils.TIMEOUT)
+    os.environ["MPLBACKEND"] = utils.MATPLOTLIB_INLINE_BACKEND
 
 
 @pytest.fixture(scope="module")

tests/test_kernel.py

@@ -408,13 +408,14 @@ class user_mod:
     kernel.user_ns = {}
 
 
-async def test_matplotlib_inline_on_import(client):
-    pytest.importorskip("matplotlib", reason="this test requires matplotlib")
+async def test_matplotlib_inline_on_import(subprocess_kernels_client):
+    import matplotlib as mpl  # noqa: PLC0415
+
+    assert mpl.get_backend() == utils.MATPLOTLIB_INLINE_BACKEND
     code = "\n".join(["import matplotlib, matplotlib.pyplot as plt", "backend = matplotlib.get_backend()"])
-    _, reply = await utils.execute(client, code, user_expressions={"backend": "backend"})
-    backend_bundle = reply["user_expressions"]["backend"]
-    assert "backend_inline" in backend_bundle["data"]["text/plain"]
-    await utils.clear_iopub(client)
+    _, reply = await utils.execute(subprocess_kernels_client, code, user_expressions={"backend": "backend"})
+    backend = eval(reply["user_expressions"]["backend"]["data"]["text/plain"])
+    assert backend == utils.MATPLOTLIB_INLINE_BACKEND
 
 
 @pytest.mark.parametrize("code", ["%connect_info", "%matplotlib --list", "%callers"])

tests/utils.py

@@ -21,6 +21,7 @@
 
 
 TIMEOUT = 10 if not async_kernel.utils.LAUNCHED_BY_DEBUGPY else 1e6
+MATPLOTLIB_INLINE_BACKEND = "module://matplotlib_inline.backend_inline"
 
 
 class ExecuteContentType(TypedDict):