Merge pull request #9814 from sinhrks/tsplot_df

BUG: Repeated time-series plot causes memory leak

Author: sinhrks

doc/source/whatsnew/v0.17.0.txt

@@ -408,7 +408,7 @@ Bug Fixes
 - Bug in ``Series.plot(kind='hist')`` Y Label not informative (:issue:`10485`)
 - Bug in ``read_csv`` when using a converter which generates a ``uint8`` type (:issue:`9266`)
 
-
+- Bug causes memory leak in time-series line and area plot (:issue:`9003`)
 
 
 - Bug in line and kde plot cannot accept multiple colors when ``subplots=True`` (:issue:`9894`)

pandas/tests/test_graphics.py

@@ -3281,6 +3281,36 @@ def test_sharey_and_ax(self):
             self.assertTrue(ax.yaxis.get_label().get_visible(),
                              "y label is invisible but shouldn't")
 
+    def test_memory_leak(self):
+        """ Check that every plot type gets properly collected. """
+        import weakref
+        import gc
+
+        results = {}
+        for kind in plotting._plot_klass.keys():
+            args = {}
+            if kind in ['hexbin', 'scatter', 'pie']:
+                df = self.hexbin_df
+                args = {'x': 'A', 'y': 'B'}
+            elif kind == 'area':
+                df = self.tdf.abs()
+            else:
+                df = self.tdf
+
+            # Use a weakref so we can see if the object gets collected without
+            # also preventing it from being collected
+            results[kind] = weakref.proxy(df.plot(kind=kind, **args))
+
+        # have matplotlib delete all the figures
+        tm.close()
+        # force a garbage collection
+        gc.collect()
+        for key in results:
+            # check that every plot was collected
+            with tm.assertRaises(ReferenceError):
+                # need to actually access something to get an error
+                results[key].lines
+
     @slow
     def test_df_grid_settings(self):
         # Make sure plot defaults to rcParams['axes.grid'] setting, GH 9792