def test_image_write_tags(self): """ write tags to an image """ shutil.copy(TEST_PLAIN, self.tmpdir) img = PictagImage(os.path.join(self.tmpdir, os.path.basename(TEST_PLAIN))) #no lat/lon/dt set on the image lat, lon = img.position_get() self.assertEqual(lat, None) self.assertEqual(lon, None) #change data (but still not written to file) img.position_set(10.0, 20.0) lat, lon = img.position_get() self.assertEqual(lat, 10) self.assertEqual(lon, 20) #open a new pictag with the same file. data is not written to file so tags should be unavailable img2 = PictagImage(os.path.join(self.tmpdir, os.path.basename(TEST_PLAIN))) lat, lon = img2.position_get() self.assertEqual(lat, None) self.assertEqual(lon, None) #write data of img img.save() #load file again. data should be written now img3 = PictagImage(os.path.join(self.tmpdir, os.path.basename(TEST_PLAIN))) lat, lon = img3.position_get() self.assertEqual(lat, 10) self.assertEqual(lon, 20)