Add test for Basemap.arcgisimage with on-the-fly cachedir creation

Author: molinav

packages/basemap/test/mpl_toolkits/basemap/test_Basemap.py

@@ -149,7 +149,7 @@ def test_arcgisimage_with_cyl(self, axs=None, axslen0=10):
         self.assertEqual(len(axs_children), axslen0 + 1)
 
     @unittest.skipIf(PIL is None, reason="pillow unavailable")
-    def test_arcgisimage_with_cyl_using_cache(self, axs=None, axslen0=10):
+    def test_arcgisimage_with_cyl_using_cache(self, existing=False, axs=None, axslen0=10):
         """Test showing an ArcGIS image as background."""
 
         axs_obj = plt.gca() if axs is None else axs
@@ -160,10 +160,13 @@ def test_arcgisimage_with_cyl_using_cache(self, axs=None, axslen0=10):
                        llcrnrlon=-90, llcrnrlat=30,
                        urcrnrlon=-60, urcrnrlat=60)
 
-        cachedir = tempfile.mkdtemp(prefix="tmp-basemap-cachedir-")
-        try:
-            # Check that the cache is initially empty.
+        # Create cache directory string and check it is empty.
+        tmpdir = tempfile.mkdtemp(prefix="tmp-basemap-cachedir-")
+        cachedir = tmpdir if existing else os.path.join(tmpdir, "cachedir")
+        if os.path.isdir(cachedir):
             self.assertEqual(len(os.listdir(cachedir)), 0)
+
+        try:
             # Check that the first call populates the cache.
             img = bmap.arcgisimage(verbose=False, cachedir=cachedir)
             self.assertEqual(len(os.listdir(cachedir)), 1)
@@ -179,7 +182,14 @@ def test_arcgisimage_with_cyl_using_cache(self, axs=None, axslen0=10):
             axs_children = axs_obj.get_children()
             self.assertEqual(len(axs_children), axslen0 + 2)
         finally:
-            shutil.rmtree(cachedir)
+            if os.path.isdir(tmpdir):
+                shutil.rmtree(tmpdir)
+
+    @unittest.skipIf(PIL is None, reason="pillow unavailable")
+    def test_arcgisimage_with_cyl_using_cache_already_existing(self):
+        """Test showing an ArcGIS image as background."""
+
+        self.test_arcgisimage_with_cyl_using_cache(existing=True)
 
     def _test_basemap_data_warpimage(self, method, axs=None, axslen0=10):
         """Test drawing a map background from :mod:`basemap_data`."""