FIX: PyAVReaderTimed.close does not close container

pims/pyav_reader.py

@@ -143,6 +143,12 @@ def __init__(self, file, cache_size=16, fast_forward_thresh=32,
 
         self._reset_demuxer()
 
+        self._is_container_closed = False
+
+    def __del__(self):
+        if not self._is_container_closed:
+            self._container.close()
+
     def __len__(self):
         return int(self._duration * self._frame_rate)
 
@@ -151,6 +157,10 @@ def _reset_demuxer(self):
         self._frame_generator = _gen_frames(demuxer, self._stream.time_base,
                                             self._frame_rate, self._first_pts)
 
+    def close(self):
+        self._container.close()
+        self._is_container_closed = True
+
     @property
     def duration(self):
         """The video duration in seconds."""
@@ -175,6 +185,10 @@ def get_frame(self, i):
         if cached_i == i:
             return cached_frame.to_frame()
 
+        # Stop before seeking to frame, to avoid crashing
+        if self._is_container_closed:
+            raise ValueError("Cannot read uncached frame from closed file. Try other frame index or re-open file.")
+
         # check if we will have to seek to the frame
         if self._last_frame >= i or \
             self._last_frame < i - self._fast_forward_thresh:

pims/tests/test_common.py

@@ -419,6 +419,28 @@ def setUp(self):
         self.expected_shape = (424, 640, 3)
         self.expected_len = 480
 
+    def test_close(self):
+        vid = self.klass(self.filename)
+
+        assert vid[10].shape == self.expected_shape
+
+        vid.close()
+
+        assert vid[9].shape == self.expected_shape
+
+        with self.assertRaises(ValueError):
+            vid[11].shape
+
+    def test_context_manager(self):
+
+        with self.klass(self.filename) as vid:
+            assert vid[10].shape == self.expected_shape
+
+        assert vid[9].shape == self.expected_shape
+
+        with self.assertRaises(ValueError):
+            vid[11].shape
+
 
 class TestVideo_PyAV_indexed(_image_series, unittest.TestCase):
     def check_skip(self):