Added test for ImageTk _get_image_from_kw

Tests/test_imagetk.py

@@ -1,15 +1,43 @@
 from helper import unittest, PillowTestCase
+from PIL import Image
 
+try:
+    from PIL import ImageTk
+    dir(ImageTk)
+except (OSError, ImportError) as v:
+    # Skipped via setUp()
+    pass
 
 class TestImageTk(PillowTestCase):
 
-    def test_import(self):
+    def setUp(self):
         try:
             from PIL import ImageTk
             dir(ImageTk)
         except (OSError, ImportError) as v:
             self.skipTest(v)
 
+    def test_kw(self):
+        TEST_JPG = "Tests/images/hopper.jpg"
+        TEST_PNG = "Tests/images/hopper.png"
+        im1 = Image.open(TEST_JPG)
+        im2 = Image.open(TEST_PNG)
+        with open(TEST_PNG, 'rb') as fp:
+            data = fp.read()
+        kw = {"file":TEST_JPG, "data":data}
+
+        # Test "file"
+        im = ImageTk._get_image_from_kw(kw)
+        self.assert_image_equal(im, im1)
+
+        # Test "data"
+        im = ImageTk._get_image_from_kw(kw)
+        self.assert_image_equal(im, im2)
+
+        # Test no relevant entry
+        im = ImageTk._get_image_from_kw(kw)
+        self.assertEqual(im, None)
+
 
 if __name__ == '__main__':
     unittest.main()