Fix error on sample log plot resize (#39248)

* fix error on sample log plot resize

* add release note

Author: MialLewis

docs/source/release/v6.13.0/Workbench/Bugfixes/39247.rst

@@ -0,0 +1 @@
+- Minimizing the sample log plot on the ``SampleLogs`` widget so that it is not visible no longer throws an error.

qt/python/mantidqt/mantidqt/widgets/samplelogs/test/test_samplelogs_view.py

@@ -48,3 +48,11 @@ def test_workspace_updates(self):
         assert pres.view.isVisible()
         DeleteWorkspace("new_name")
         assert not pres.view.isVisible()
+
+    def test_minimum_canvas_size(self):
+        ws = CreateSampleWorkspace()
+        pres = SampleLogs(ws)
+        pres.view.show_plot_and_stats(True)
+        pres.view.canvas.resize(-1, -1)
+        self.assertEqual(0, pres.view.canvas.width())
+        self.assertEqual(0, pres.view.canvas.height())

qt/python/mantidqt/mantidqt/widgets/samplelogs/view.py

@@ -24,7 +24,7 @@
     QFrame,
     QSpacerItem,
 )
-from qtpy.QtCore import QItemSelectionModel, Qt, Signal
+from qtpy.QtCore import QItemSelectionModel, Qt, Signal, QSize
 from mantidqt.widgets.observers.observing_view import ObservingView
 from mantidqt.MPLwidgets import FigureCanvas
 from mantid.api import Workspace
@@ -123,6 +123,7 @@ def __init__(self, presenter, parent=None, window_flags=Qt.Window, name="", isMD
         self.fig = Figure()
         self.canvas = FigureCanvas(self.fig)
         self.canvas.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Expanding)
+        self.canvas.setMinimumSize(QSize(0, 0))
         self.canvas.mpl_connect("button_press_event", self.presenter.plot_clicked)
         self.ax = self.fig.add_subplot(111, projection="mantid")
         layout_right.addWidget(self.canvas)
@@ -169,7 +170,7 @@ def set_model(self, model):
         self.table.selectionModel().selectionChanged.connect(self.presenter.update)
 
     def show_plot_and_stats(self, show_plot_and_stats):
-        """sets wether the plot and stats section should be visible"""
+        """sets whether the plot and stats section should be visible"""
         if self.frame_right.isVisible() != show_plot_and_stats:
             # the desired state is nor the current state
             self.setUpdatesEnabled(False)