Path: Relocate valueChanged signal translation to QSB class

Moved the translation method from PathFeatureExtensionsGui module to proper location within QuantitySpinBox class in PathGui module.
This change adds a missing translation method for passing the `editingFinished` signal to the parent task panel when the user is finished editing a QuantitySpinBox object with an active expression in the Gui.
If no expression is active, this new method is dormant.

Some cleanup of initial changes related to development of this fix are included.

src/Mod/Path/PathScripts/PathFeatureExtensionsGui.py

@@ -285,7 +285,7 @@ class TaskPanelExtensionPage(PathOpGui.TaskPanelPage):
         self._initializeExtensions(obj)  # Efficiently initialize Extensions
         self.defaultLength.updateSpinBox()
         self._getUseOutlineState()  # Find `useOutline` checkbox and get its boolean value
-        self.lastDefaultLength = self.form.defaultLength.text()
+        self.lastDefaultLength = self.form.defaultLength.text()  # set last DL value
         self.fieldsSet = True  # flag to identify initial values set
 
     def _initializeExtensions(self, obj):
@@ -301,33 +301,16 @@ class TaskPanelExtensionPage(PathOpGui.TaskPanelPage):
             self.form.extensionEdit.setDisabled(True)
         self.setExtensions(self.extensions)
 
-    def _isDefaultLengthExpression(self):
-        """_isDefaultLengthExpression()... Return True if Default Length is determined by an expression."""
-        for prop, __ in self.obj.ExpressionEngine:
-            if prop == "ExtensionLengthDefault":
-                return True
-        return False
-
     def _applyDefaultLengthChange(self, index=None):
         """_applyDefaultLengthChange(index=None)...
-        Helper method to update Default Length spinbox, and update extensions due to change in Default Length."""
+        Helper method to update Default Length spinbox,
+        and update extensions due to change in Default Length."""
         self.defaultLength.updateSpinBox()
         if self.form.defaultLength.text() != self.lastDefaultLength:
             self.lastDefaultLength = self.form.defaultLength.text()
             self._resetCachedExtensions()  # Reset extension cache because extension dimensions likely changed
             self._enableExtensions()  # Recalculate extensions
 
-    def _defaultLengthChanged(self):
-        """_defaultLengthChanged()... Slot method for determining if a change in Default Length
-        value is determined from an expression edit, or a simple spinbox change. If the former,
-        emit a `editingFinished` signal manually because the Formula Editor window returned
-        a value to the base SpinBox."""
-        if (
-            self._isDefaultLengthExpression()
-            and self.form.defaultLength.text() != self.lastDefaultLength
-        ):
-            self.form.defaultLength.editingFinished.emit()
-
     def createItemForBaseModel(self, base, sub, edges, extensions):
         PathLog.track(
             base.Label, sub, "+", len(edges), len(base.Shape.getElement(sub).Edges)
@@ -645,10 +628,7 @@ class TaskPanelExtensionPage(PathOpGui.TaskPanelPage):
         self.form.buttonDisable.clicked.connect(self.extensionsDisable)
         self.form.buttonEnable.clicked.connect(self.extensionsEnable)
         self.form.enableExtensions.toggled.connect(self._enableExtensions)
-
-        # These two handlers are needed to provide immediate updates to extension length
         self.form.defaultLength.editingFinished.connect(self._applyDefaultLengthChange)
-        self.form.defaultLength.textChanged.connect(self._defaultLengthChanged)
 
         self.model.itemChanged.connect(self.updateItemEnabled)
 

src/Mod/Path/PathScripts/PathGui.py

@@ -125,14 +125,29 @@ class QuantitySpinBox(QtCore.QObject):
         self.onBeforeChange = onBeforeChange
         self.prop = None
         self.obj = obj
+        self.lastWidgetText = self.widget.text()
         self.attachTo(obj, prop)
         self.widget.installEventFilter(self)
+        # Connect local class method as slot
+        self.widget.textChanged.connect(self.onWidgetValueChanged)
 
     def eventFilter(self, obj, event):
         if event.type() == QtCore.QEvent.Type.FocusIn:
             self.updateSpinBox()
         return False
 
+    def onWidgetValueChanged(self):
+        """onWidgetValueChanged()... Slot method for determining if a change
+        in widget value is a result of an expression edit, or a simple spinbox change.
+        If the former, emit a manual `editingFinished` signal because the Formula Editor
+        window returned a value to the base widget, leaving it in read-only mode,
+        and finishing the editing of the value. Otherwise, due nothing if the value
+        has not changed, or there is no active expression for the property.
+        If the user closes the Formula Editor to cancel the edit, the value will not
+        be changed, and this manual signal will not be emitted."""
+        if self._hasExpression() and self.widget.text() != self.lastWidgetText:
+            self.widget.editingFinished.emit()
+
     def attachTo(self, obj, prop=None):
         """attachTo(obj, prop=None) ... use an existing editor for the given object and property"""
         PathLog.track(self.prop, prop)
@@ -180,6 +195,7 @@ class QuantitySpinBox(QtCore.QObject):
                     quantity = PathUtil.getProperty(self.obj, self.prop)
             value = quantity.Value if hasattr(quantity, "Value") else quantity
             self.widget.setProperty("rawValue", value)
+            self.lastWidgetText = self.widget.text()  # update last widget value
             if expr:
                 self.widget.setReadOnly(True)
                 self.widget.setStyleSheet("color: gray")