Start stability tests:

- randomly add / remove widgets and graphicsitems to provoke a crash
 - create and delete various objects and ensure that nothing is left in memory

pyqtgraph/tests/test_ref_cycles.py

@@ -0,0 +1,45 @@
+"""
+Test for unwanted reference cycles
+
+"""
+import pyqtgraph as pg
+import numpy as np
+import gc
+app = pg.mkQApp()
+
+def processEvents():
+    for i in range(3):
+        gc.collect()
+        app.processEvents()
+        # processEvents ignored DeferredDelete events; we must process these
+        # manually.
+        app.sendPostedEvents(None, pg.QtCore.QEvent.DeferredDelete)
+
+def test_PlotItem():
+    for i in range(10):
+        plt = pg.PlotItem()
+        plt.plot(np.random.normal(size=10000))
+    processEvents()
+    
+    ot = pg.debug.ObjTracker()
+    
+    plots = []
+    for i in range(10):
+        plt = pg.PlotItem()
+        plt.plot(np.random.normal(size=10000))
+        plots.append(plt)
+    processEvents()
+
+    ot.diff()
+    
+    del plots
+    processEvents()
+    
+    ot.diff()
+    
+    
+    return ot
+
+    
+if __name__ == '__main__':
+    ot = test_PlotItem()

pyqtgraph/tests/test_stability.py

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+"""
+PyQt/PySide stress test:
+
+Create lots of random widgets and graphics items, connect them together randomly,
+the tear them down repeatedly. 
+
+The purpose of this is to attempt to generate segmentation faults.
+"""
+import pyqtgraph as pg
+import random
+
+random.seed(12345)
+
+widgetTypes = [pg.PlotWidget, pg.ImageView, pg.GraphicsView, pg.QtGui.QWidget,
+               pg.QtGui.QTreeWidget, pg.QtGui.QPushButton]
+
+itemTypes = [pg.PlotCurveItem, pg.ImageItem, pg.PlotDataItem, pg.ViewBox,
+             pg.QtGui.QGraphicsRectItem]
+
+while True:
+    action = random.randint(0,5)
+    if action == 0:
+        # create a widget
+        pass
+    elif action == 1:
+        # set parent (widget or None), possibly create a reference in either direction
+        pass
+    elif action == 2:
+        # 
+        pass
+    elif action == 3:
+        pass
+        
+
+
+
+
+
+