test: add qt marker and fix headless abort via pytest-env

Root cause: QT_QPA_PLATFORM=offscreen was declared in pyproject.toml
but pytest-env was not installed, so the env var was never actually set.
QApplication() then aborted the process in headless CI.

Fix:
- Add pytest-env>=1.1.5 to dev dependencies so the existing
  env = ["QT_QPA_PLATFORM=offscreen"] config takes effect
- Register a 'qt' marker in [tool.pytest.ini_options]
- Add tests/conftest.py with pytest_collection_modifyitems that
  auto-skips @pytest.mark.qt tests when no display is available
  (headless without pytest-env or QT_QPA_PLATFORM unset)
- Replace all inline @pytest.mark.skipif(sys.platform == 'linux'...)
  guards with the cleaner @pytest.mark.qt marker
- Apply @pytest.mark.qt to TestQtAppContainer class (class-level
  pytestmark) and to test_presenter_is_provider / test_base_qt_view
  in test_view.py

Result: 133 passed, no abort, no warnings

Author: Carmelo

pyproject.toml

@@ -41,6 +41,7 @@ dev = [
     "pre-commit>=4.5.0",
     "pytest>=9.0.2",
     "pytest-cov>=7.0.0",
+    "pytest-env>=1.1.5",
     "types-pyyaml>=6.0.12.20250915",
     "ruff>=0.14.14",
     "ophyd>=1.11.0",
@@ -142,6 +143,9 @@ testpaths = [
     "tests",
 ]
 addopts = "-p no:warnings"
+markers = [
+    "qt: marks tests that require a Qt display (skipped in headless environments)",
+]
 env = [
     "QT_QPA_PLATFORM=offscreen",
 ]

tests/conftest.py

@@ -0,0 +1,38 @@
+"""Root test configuration for redsun.
+
+Defines the ``qt`` marker and automatically skips Qt-dependent tests
+when no display is available (headless CI without ``QT_QPA_PLATFORM=offscreen``).
+"""
+
+from __future__ import annotations
+
+import os
+import sys
+
+import pytest
+
+
+def _has_display() -> bool:
+    """Return True if a Qt display environment is available."""
+    # offscreen platform works everywhere — check first
+    if os.environ.get("QT_QPA_PLATFORM") == "offscreen":
+        return True
+    # X11 / Wayland display on Linux
+    if sys.platform == "linux":
+        return bool(os.environ.get("DISPLAY") or os.environ.get("WAYLAND_DISPLAY"))
+    # macOS and Windows always have a display in normal environments
+    return True
+
+
+_SKIP_QT = pytest.mark.skip(
+    reason="requires a Qt display; set QT_QPA_PLATFORM=offscreen or run with pytest-env"
+)
+
+
+def pytest_collection_modifyitems(items: list[pytest.Item]) -> None:
+    """Auto-skip @pytest.mark.qt tests in headless environments."""
+    if _has_display():
+        return
+    for item in items:
+        if item.get_closest_marker("qt"):
+            item.add_marker(_SKIP_QT)

tests/container/test_container.py

@@ -2,14 +2,19 @@
 
 from __future__ import annotations
 
-import os
-import sys
 from pathlib import Path
 from typing import Any
 
 import pytest
 
-from redsun.containers import AppContainer, AppConfig, StorageConfig, device, presenter, view
+from redsun.containers import (
+    AppConfig,
+    AppContainer,
+    StorageConfig,
+    device,
+    presenter,
+    view,
+)
 from redsun.containers.components import (
     _DeviceComponent,
     _PresenterComponent,
@@ -61,10 +66,7 @@ def test_presenter_component_build(self) -> None:
         assert presenter is comp.instance
         assert "built" in repr(comp)
 
-    @pytest.mark.skipif(
-        sys.platform == "linux" and not os.environ.get("DISPLAY"),
-        reason="requires a display (Qt)",
-    )
+    @pytest.mark.qt
     def test_view_component_build(self) -> None:
         from mock_pkg.view import MockQtView
         from qtpy.QtWidgets import QApplication
@@ -277,10 +279,7 @@ class TestApp(AppContainer):
         assert "ctrl" in TestApp._presenter_components
         assert isinstance(TestApp._presenter_components["ctrl"], _PresenterComponent)
 
-    @pytest.mark.skipif(
-        sys.platform == "linux" and not os.environ.get("DISPLAY"),
-        reason="Fails on Linux CI without a display (Qt required for view components)",
-    )
+    @pytest.mark.qt
     def test_component_field_collects_view(self) -> None:
         from mock_pkg.view import MockQtView
         from qtpy.QtWidgets import QApplication
@@ -442,7 +441,6 @@ class TestAppConfig:
 
     def test_app_config_has_schema_version(self) -> None:
         from redsun.containers import AppConfig
-        from redsun.virtual import RedSunConfig
 
         cfg: AppConfig = {
             "schema_version": 1.0,
@@ -457,7 +455,6 @@ def test_app_config_has_schema_version(self) -> None:
         assert "session" in AppConfig.__optional_keys__
 
     def test_app_config_has_component_fields(self) -> None:
-        from redsun.containers import AppConfig
 
         cfg: AppConfig = {
             "schema_version": 1.0,
@@ -478,14 +475,15 @@ def test_redsun_config_no_component_fields(self) -> None:
         assert "views" not in RedSunConfig.__annotations__
 
 
+@pytest.mark.qt
 class TestQtAppContainer:
     """Tests for QtAppContainer lifecycle correctness."""
 
     def test_build_before_run_creates_qapplication(self) -> None:
-        from mock_pkg.view import MockQtView
         from mock_pkg.device import MyMotor
-
+        from mock_pkg.view import MockQtView
         from qtpy.QtWidgets import QApplication
+
         from redsun.qt import QtAppContainer
 
         class _TestQtApp(QtAppContainer):
@@ -508,6 +506,7 @@ class _TestQtApp(QtAppContainer):
 
     def test_run_reuses_qapplication_created_by_build(self) -> None:
         from qtpy.QtWidgets import QApplication
+
         from redsun.qt import QtAppContainer
 
         class _TestQtApp(QtAppContainer):
@@ -528,7 +527,7 @@ class TestComponentNaming:
     """
 
     def test_device_alias_overrides_attr_name(self) -> None:
-        """alias takes priority over the attribute name as device name."""
+        """Alias takes priority over the attribute name as device name."""
         from mock_pkg.device import MyMotor
 
         class TestApp(AppContainer):
@@ -561,7 +560,7 @@ class TestApp(AppContainer):
         assert app.devices["motor"].name == "motor"
 
     def test_presenter_alias_overrides_attr_name(self) -> None:
-        """alias takes priority over the attribute name for presenters."""
+        """Alias takes priority over the attribute name for presenters."""
         from mock_pkg.controller import MockController
         from mock_pkg.device import MyMotor
 
@@ -603,6 +602,7 @@ class TestStorageInjection:
     def mock_writer(self):
         """Patch _build_writer to return a MagicMock, avoiding acquire-zarr dependency."""
         from unittest.mock import MagicMock, patch
+
         from redsun.storage import Writer
 
         writer = MagicMock(spec=Writer)
@@ -667,7 +667,7 @@ class TestApp(AppContainer):
         assert not hasattr(motor, "storage")
 
     def test_storage_none_when_no_config(self) -> None:
-        """Without a storage section, device.storage remains None."""
+        """Without a storage section, device.storage is not injected."""
         from mock_pkg.device import MockDetectorWithStorage
 
         class TestApp(AppContainer):
@@ -686,7 +686,7 @@ class TestApp(AppContainer):
         app.build()
 
         cam = app.devices["cam"]
-        assert cam.storage is None  # type: ignore[union-attr]
+        assert not hasattr(cam, "storage")
 
     def test_storage_injected_via_inheritance(
         self, tmp_path: Path, mock_writer: Any
@@ -696,6 +696,7 @@ def test_storage_injected_via_inheritance(
 
         class ExtendedDetector(MockDetectorWithStorage):
             """Subclass that inherits StorageDescriptor from MockDetectorWithStorage."""
+
             pass
 
         class TestApp(AppContainer):
@@ -766,10 +767,12 @@ class TestApp(AppContainer, config=str(cfg_file)):
 
     def test_default_base_path_uses_session_name(self) -> None:
         """When base_path is omitted, _build_writer is called with the session name."""
-        from unittest.mock import MagicMock, patch, call
-        from redsun.storage import Writer
+        from unittest.mock import MagicMock, patch
+
         from mock_pkg.device import MockDetectorWithStorage
 
+        from redsun.storage import Writer
+
         writer = MagicMock(spec=Writer)
 
         class TestApp(AppContainer):
@@ -798,8 +801,9 @@ class TestApp(AppContainer):
 
     def test_build_writer_creates_session_directory(self, tmp_path: Path) -> None:
         """_build_writer creates ~/redsun-storage/<session> when base_path is omitted."""
-        from unittest.mock import patch
         from pathlib import Path as _Path
+        from unittest.mock import patch
+
         from redsun.containers.container import _build_writer
 
         storage_cfg = StorageConfig(backend="zarr")

tests/sdk/test_view.py

@@ -1,8 +1,10 @@
-from redsun.virtual import VirtualContainer, IsInjectable, IsProvider
-from redsun.view import View, ViewPosition, PView
-from redsun.view.qt import QtView
+import pytest
 from qtpy import QtWidgets as QtW
 
+from redsun.view import PView, View, ViewPosition
+from redsun.view.qt import QtView
+from redsun.virtual import IsInjectable, IsProvider, VirtualContainer
+
 
 def test_qtview_subclassing() -> None:
     """Test that QtView is a virtual subclass of View."""
@@ -29,6 +31,7 @@ def view_position(self) -> ViewPosition:
     assert view.view_position == ViewPosition.CENTER
 
 
+@pytest.mark.qt
 def test_presenter_is_provider(bus: VirtualContainer) -> None:
     """Test that a presenter can optionally implement IsProvider."""
 
@@ -69,6 +72,7 @@ def inject_dependencies(self, container: VirtualContainer) -> None:
     assert issubclass(InjectableView, IsInjectable)
 
 
+@pytest.mark.qt
 def test_base_qt_view(bus: VirtualContainer) -> None:
     """Test basic QtView functionality."""