REF: create a window singleton for access throughout superscore

docs/source/upcoming_release_notes/115-ref_window_singleton.rst

@@ -0,0 +1,23 @@
+115 ref_window_singleton
+########################
+
+API Breaks
+----------
+- N/A
+
+Features
+--------
+- N/A
+
+Bugfixes
+--------
+- N/A
+
+Maintenance
+-----------
+- Makes Window a QtSingleton, and adds an access function for use throughout superscore ui widgets
+  Uses this singleton to access methods that were passed around manually in the past as optional arguments or set attributes (open_page_slot, client)
+
+Contributors
+------------
+- tangkong

superscore/tests/conftest.py

@@ -17,6 +17,7 @@
                               Root, Setpoint, Severity, Snapshot, Status)
 from superscore.tests.ioc import IOCFactory
 from superscore.widgets.views import EntryItem
+from superscore.widgets.window import Window
 
 
 def linac_data() -> Root:
@@ -1003,3 +1004,10 @@ def nest_depth(entry: Union[Nestable, EntryItem]) -> int:
                 q.append((child, depth+1))
 
     return max(depths)
+
+
+@pytest.fixture(autouse=True)
+def teardown_window_singleton():
+    # clean up window autouse fixture inside this module only
+    yield
+    Window._instance = None

superscore/tests/test_page.py

@@ -1,6 +1,6 @@
 """Largely smoke tests for various pages"""
 
-from unittest.mock import MagicMock, patch
+from unittest.mock import MagicMock, PropertyMock, patch
 
 import pytest
 from pytestqt.qtbot import QtBot
@@ -219,10 +219,11 @@ def test_open_page_slot(
     page_fixture: str,
     request: pytest.FixtureRequest,
 ):
-    page: BaseParameterPage = request.getfixturevalue(page_fixture)
-    page.open_page_slot = MagicMock()
-    page.open_rbv_button.clicked.emit()
-    assert page.open_page_slot.called
+    with patch("superscore.widgets.page.entry.BaseParameterPage.open_page_slot",
+               new_callable=PropertyMock):
+        page: BaseParameterPage = request.getfixturevalue(page_fixture)
+        page.open_rbv_button.clicked.emit()
+        assert page.open_page_slot.called
 
 
 @pytest.mark.parametrize(

superscore/widgets/__init__.py

@@ -16,3 +16,18 @@ def _get_icon_map():
 
 
 ICON_MAP = _get_icon_map()
+
+
+def get_window():
+    """
+    Return the window singleton if it already exists, to allow other widgets to
+    access its members.
+    Must not be called in the code path that results from Window.__init__.
+    A good (safe) rule of thumb is to make sure this function cannot be reached
+    from any widget's __init__ method.
+    Hides import in __init__ to avoid circular imports.
+    """
+    from .window import Window
+    if Window._instance is None:
+        return
+    return Window()

superscore/widgets/core.py

@@ -4,15 +4,17 @@
 from __future__ import annotations
 
 from pathlib import Path
-from typing import ClassVar, List
+from typing import ClassVar, List, Optional
 from weakref import WeakValueDictionary
 
 from pcdsutils.qt.designer_display import DesignerDisplay
 from qtpy import QtCore, QtWidgets
 
+from superscore.client import Client
 from superscore.qt_helpers import QDataclassBridge, QDataclassList
-from superscore.type_hints import AnyDataclass
+from superscore.type_hints import AnyDataclass, OpenPageSlot
 from superscore.utils import SUPERSCORE_SOURCE_PATH
+from superscore.widgets import get_window
 from superscore.widgets.manip_helpers import (FrameOnEditFilter,
                                               match_line_edit_text_width)
 
@@ -423,3 +425,43 @@ def __call__(cls, *args, **kwargs):
         if cls._instance is None:
             cls._instance = super().__call__(*args, **kwargs)
         return cls._instance
+
+
+class WindowLinker:
+    """
+    Mixin class that provides access methods for resources held by the main Window.
+    These include:
+    - client: first attempts to grab the client set at init, if none exists use
+              the Window's client
+    - open_page_slot: grabs the slot from the Window
+    """
+
+    def __init__(self, *args, client: Optional[Client] = None, **kwargs) -> None:
+        self._client = client
+        super().__init__(*args, **kwargs)
+
+    @property
+    def client(self) -> Optional[Client]:
+        # Return the provided client if it exists, grab the Window's otherwise
+        if self._client is not None:
+            return self._client
+        else:
+            window = get_window()
+            if window is not None:
+                return window.client
+
+    @client.setter
+    def client(self, client: Client):
+        if not isinstance(client, Client):
+            raise TypeError(f"Cannot set a {type(client)} as a client")
+
+        if client is self._client:
+            return
+
+        self._client = client
+
+    @property
+    def open_page_slot(self) -> Optional[OpenPageSlot]:
+        window = get_window()
+        if window is not None:
+            return window.open_page

superscore/widgets/page/collection_builder.py

@@ -4,10 +4,9 @@
 from qtpy import QtCore, QtWidgets
 from qtpy.QtGui import QCloseEvent
 
-from superscore.client import Client
 from superscore.model import Collection, Entry, Parameter
-from superscore.type_hints import OpenPageSlot
-from superscore.widgets.core import DataWidget, Display, NameDescTagsWidget
+from superscore.widgets.core import (DataWidget, Display, NameDescTagsWidget,
+                                     WindowLinker)
 from superscore.widgets.enhanced import FilterComboBox
 from superscore.widgets.manip_helpers import insert_widget
 from superscore.widgets.views import (BaseTableEntryModel, LivePVHeader,
@@ -17,7 +16,7 @@
 logger = logging.getLogger(__name__)
 
 
-class CollectionBuilderPage(Display, DataWidget):
+class CollectionBuilderPage(Display, DataWidget, WindowLinker):
     filename = 'collection_builder_page.ui'
     data: Collection
 
@@ -46,16 +45,12 @@ class CollectionBuilderPage(Display, DataWidget):
     def __init__(
         self,
         *args,
-        client: Client,
         data: Optional[Collection] = None,
-        open_page_slot: Optional[OpenPageSlot] = None,
         **kwargs
     ):
         if data is None:
             data = Collection()
         super().__init__(*args, data=data, **kwargs)
-        self.client = client
-        self.open_page_slot = open_page_slot
         self.tree_model = None
         self._coll_options: list[Collection] = []
         self._title = self.data.title
@@ -90,7 +85,6 @@ def setup_ui(self):
 
         self.tree_view.client = self.client
         self.tree_view.set_data(self.data)
-        self.tree_view.open_page_slot = self.open_page_slot
         self.tree_model: RootTree = self.tree_view.model()
 
         self.sub_coll_table_view.data_updated.connect(self.tree_model.refresh_tree)

superscore/widgets/page/diff.py

@@ -7,11 +7,9 @@
 from PyQt5.QtGui import QCloseEvent
 from qtpy import QtCore, QtGui, QtWidgets
 
-from superscore.client import Client
 from superscore.compare import DiffType, EntryDiff
 from superscore.model import Entry
-from superscore.type_hints import OpenPageSlot
-from superscore.widgets.core import Display
+from superscore.widgets.core import Display, WindowLinker
 from superscore.widgets.views import (EntryItem, LivePVHeader,
                                       LivePVTableModel, LivePVTableView,
                                       NestableHeader, NestableTableModel,
@@ -246,7 +244,7 @@ class Side(Flag):
     RIGHT = False
 
 
-class DiffPage(Display, QtWidgets.QWidget):
+class DiffPage(Display, QtWidgets.QWidget, WindowLinker):
     """
     Diff View Page.  Compares two ``Entry`` objects, attempting to highlight
     differences where appropriate
@@ -285,17 +283,13 @@ class DiffPage(Display, QtWidgets.QWidget):
     def __init__(
         self,
         *args,
-        client: Client,
-        open_page_slot: Optional[OpenPageSlot] = None,
         l_entry: Optional[Entry] = None,
         r_entry: Optional[Entry] = None,
         **kwargs
     ):
         super().__init__(*args, **kwargs)
-        self.client = client
         self.l_entry = l_entry
         self.r_entry = r_entry
-        self.open_page_slot = open_page_slot
         self._linked_uuids: Dict[UUID, UUID] = BiDict()
 
         self.widget_map = {
@@ -332,13 +326,11 @@ def setup_ui(self):
 
             pv_view: LivePVTableView = self.widget_map[side]['pv']
             pv_view._model_cls = DiffPVTableModel
-            pv_view.open_page_slot = self.open_page_slot
             pv_view.client = self.client
 
             nest_view: NestableTableView = self.widget_map[side]['nest']
             nest_view._model_cls = DiffNestableTableModel
             nest_view.client = self.client
-            nest_view.open_page_slot = self.open_page_slot
 
         self.set_entry(self.l_entry, Side.LEFT)
         self.set_entry(self.r_entry, Side.RIGHT)

superscore/widgets/page/entry.py

@@ -9,12 +9,12 @@
 from qtpy import QtWidgets
 from qtpy.QtGui import QCloseEvent
 
-from superscore.client import Client
 from superscore.control_layers._base_shim import EpicsData
 from superscore.model import (Collection, Nestable, Parameter, Readback,
                               Setpoint, Severity, Snapshot, Status)
-from superscore.type_hints import AnyEpicsType, OpenPageSlot
-from superscore.widgets.core import DataWidget, Display, NameDescTagsWidget
+from superscore.type_hints import AnyEpicsType
+from superscore.widgets.core import (DataWidget, Display, NameDescTagsWidget,
+                                     WindowLinker)
 from superscore.widgets.manip_helpers import (insert_widget,
                                               match_line_edit_text_width)
 from superscore.widgets.thread_helpers import BusyCursorThread
@@ -25,7 +25,7 @@
 logger = logging.getLogger(__name__)
 
 
-class NestablePage(Display, DataWidget):
+class NestablePage(Display, DataWidget, WindowLinker):
     filename = 'nestable_page.ui'
 
     meta_placeholder: QtWidgets.QWidget
@@ -42,15 +42,11 @@ def __init__(
         self,
         *args,
         data: Nestable,
-        client: Client,
         editable: bool = False,
-        open_page_slot: Optional[OpenPageSlot] = None,
         **kwargs
     ):
         super().__init__(*args, data=data, **kwargs)
-        self.client = client
         self.editable = editable
-        self.open_page_slot = open_page_slot
         self._last_data = deepcopy(self.data)
         self.setup_ui()
 
@@ -61,7 +57,6 @@ def setup_ui(self):
         # show tree view
         self.tree_view.client = self.client
         self.tree_view.set_data(self.data)
-        self.tree_view.open_page_slot = self.open_page_slot
 
         self.sub_pv_table_view.client = self.client
         self.sub_pv_table_view.set_data(self.data)
@@ -115,7 +110,7 @@ class SnapshotPage(NestablePage):
     data: Snapshot
 
 
-class BaseParameterPage(Display, DataWidget):
+class BaseParameterPage(Display, DataWidget, WindowLinker):
     filename = 'parameter_page.ui'
 
     meta_placeholder: QtWidgets.QWidget
@@ -159,15 +154,11 @@ class BaseParameterPage(Display, DataWidget):
     def __init__(
         self,
         *args,
-        client: Client,
         editable: bool = False,
-        open_page_slot: Optional[OpenPageSlot] = None,
         **kwargs
     ):
         super().__init__(*args, **kwargs)
-        self.client = client
         self.editable = editable
-        self.open_page_slot = open_page_slot
         self.value_stored_widget = None
         self.edata = None
         self._edata_thread: Optional[BusyCursorThread] = None

superscore/widgets/page/search.py

@@ -9,18 +9,17 @@
 from qtpy import QtCore, QtWidgets
 
 from superscore.backends.core import SearchTerm
-from superscore.client import Client
 from superscore.model import Collection, Entry, Readback, Setpoint, Snapshot
 from superscore.type_hints import OpenPageSlot
-from superscore.widgets import ICON_MAP
-from superscore.widgets.core import Display
+from superscore.widgets import ICON_MAP, get_window
+from superscore.widgets.core import Display, WindowLinker
 from superscore.widgets.views import (BaseTableEntryModel, ButtonDelegate,
                                       HeaderEnum)
 
 logger = logging.getLogger(__name__)
 
 
-class SearchPage(Display, QtWidgets.QWidget):
+class SearchPage(Display, QtWidgets.QWidget, WindowLinker):
     """
     Widget for searching and displaying Entry's.  Contains a variety of filter
     option input widgets, a sortable table view, and a filter management table.
@@ -56,13 +55,9 @@ class SearchPage(Display, QtWidgets.QWidget):
     def __init__(
         self,
         *args,
-        client: Client,
-        open_page_slot: Optional[OpenPageSlot] = None,
         **kwargs
     ) -> None:
         super().__init__(*args, **kwargs)
-        self.client = client
-        self.open_page_slot = open_page_slot
         self.model: Optional[ResultModel] = None
 
         self.type_checkboxes: List[QtWidgets.QCheckBox] = [
@@ -86,7 +81,7 @@ def setup_ui(self) -> None:
 
         # set up filter table view
         self.model = ResultModel(entries=[])
-        self.proxy_model = ResultFilterProxyModel(open_page_slot=self.open_page_slot)
+        self.proxy_model = ResultFilterProxyModel()
         self.proxy_model.setSourceModel(self.model)
         self.results_table_view.setModel(self.proxy_model)
         self.results_table_view.setSortingEnabled(True)
@@ -235,13 +230,17 @@ class ResultFilterProxyModel(QtCore.QSortFilterProxyModel):
     def __init__(
         self,
         *args,
-        open_page_slot: Optional[OpenPageSlot] = None,
         **kwargs
     ) -> None:
         super().__init__(*args, **kwargs)
-        self.open_page_slot = open_page_slot
         self.name_regexp = QtCore.QRegularExpression()
 
+    @property
+    def open_page_slot(self) -> Optional[OpenPageSlot]:
+        window = get_window()
+        if window is not None:
+            return window.open_page
+
     def filterAcceptsRow(
         self,
         source_row: int,