Merge from 3.x: PR #7234

Fixes #7157
Fixes #5830

spyder/app/mainwindow.py

@@ -23,6 +23,7 @@
 
 import atexit
 import errno
+import gc
 import os
 import os.path as osp
 import re
@@ -1950,6 +1951,10 @@ def show_toolbars(self):
         self._update_show_toolbars_action()
 
     # --- Other
+    def free_memory(self):
+        """Free memory after event."""
+        gc.collect()
+
     def plugin_focus_changed(self):
         """Focus has changed from one plugin to another"""
         self.update_edit_menu()

spyder/plugins/variableexplorer.py

@@ -7,7 +7,7 @@
 """Variable Explorer Plugin"""
 
 # Third party imports
-from qtpy.QtCore import Signal, Slot
+from qtpy.QtCore import QTimer, Signal, Slot
 from qtpy.QtWidgets import QGroupBox, QStackedWidget, QVBoxLayout
 
 # Local imports
@@ -60,6 +60,8 @@ class VariableExplorer(SpyderPluginWidget):
 
     CONF_SECTION = 'variable_explorer'
     CONFIGWIDGET_CLASS = VariableExplorerConfigPage
+    INITIAL_FREE_MEMORY_TIME_TRIGGER = 60 * 1000  # ms
+    SECONDARY_FREE_MEMORY_TIME_TRIGGER = 180 * 1000  # ms
     sig_option_changed = Signal(str, object)
 
     def __init__(self, parent):
@@ -114,6 +116,15 @@ def change_option(self, option_name, new_value):
             new_value = new_value[1:]
         self.sig_option_changed.emit(option_name, new_value)
 
+    @Slot()
+    def free_memory(self):
+        """Free memory signal."""
+        self.main.free_memory()
+        QTimer.singleShot(self.INITIAL_FREE_MEMORY_TIME_TRIGGER,
+                          lambda: self.main.free_memory())
+        QTimer.singleShot(self.SECONDARY_FREE_MEMORY_TIME_TRIGGER,
+                          lambda: self.main.free_memory())
+
     # ----- Stack accesors ----------------------------------------------------
     def set_current_widget(self, nsb):
         self.stack.setCurrentWidget(nsb)
@@ -147,6 +158,7 @@ def add_shellwidget(self, shellwidget):
             nsb.set_shellwidget(shellwidget)
             nsb.setup(**self.get_settings())
             nsb.sig_option_changed.connect(self.change_option)
+            nsb.sig_free_memory.connect(self.free_memory)
             self.add_widget(nsb)
             self.shellwidgets[shellwidget_id] = nsb
             self.set_shellwidget_from_id(shellwidget_id)

spyder/widgets/variableexplorer/collectionseditor.py

@@ -407,6 +407,7 @@ def setData(self, index, value, role=Qt.EditRole):
 
 class CollectionsDelegate(QItemDelegate):
     """CollectionsEditor Item Delegate"""
+    sig_free_memory = Signal()
 
     def __init__(self, parent=None):
         QItemDelegate.__init__(self, parent)
@@ -589,7 +590,7 @@ def editor_rejected(self, editor_id):
 
     def free_memory(self):
         """Free memory after closing an editor."""
-        gc.collect()
+        self.sig_free_memory.emit()
 
     def commitAndCloseEditor(self):
         """Overriding method commitAndCloseEditor"""
@@ -667,7 +668,8 @@ class BaseTableView(QTableView):
     sig_option_changed = Signal(str, object)
     sig_files_dropped = Signal(list)
     redirect_stdio = Signal(bool)
-
+    sig_free_memory = Signal()
+
     def __init__(self, parent):
         QTableView.__init__(self, parent)
         self.array_filename = None
@@ -1461,6 +1463,7 @@ def __init__(self, parent, data, minmax=False, shellwidget=None,
         self.setModel(self.model)
 
         self.delegate = RemoteCollectionsDelegate(self)
+        self.delegate.sig_free_memory.connect(self.sig_free_memory.emit)
         self.setItemDelegate(self.delegate)
 
         self.setup_table()

spyder/widgets/variableexplorer/namespacebrowser.py

@@ -44,7 +44,8 @@ class NamespaceBrowser(QWidget):
     """Namespace browser (global variables explorer widget)"""
     sig_option_changed = Signal(str, object)
     sig_collapse = Signal()
-
+    sig_free_memory = Signal()
+
     def __init__(self, parent, options_button=None, menu=None,
                  plugin_actions=None):
         QWidget.__init__(self, parent)
@@ -118,6 +119,7 @@ def setup(self, check_all=None, exclude_private=None,
 
         self.editor.sig_option_changed.connect(self.sig_option_changed.emit)
         self.editor.sig_files_dropped.connect(self.import_data)
+        self.editor.sig_free_memory.connect(self.sig_free_memory.emit)
 
         # Setup layout
         blayout = QHBoxLayout()