Merge pull request jiaaro#399 from DriverX/patch-1

Fix read headers from empty wav

pydub/audio_segment.py

@@ -93,7 +93,7 @@ def extract_wav_headers(data):
     # def search_subchunk(data, subchunk_id):
     pos = 12  # The size of the RIFF chunk descriptor
     subchunks = []
-    while pos + 8 < len(data) and len(subchunks) < 10:
+    while pos + 8 <= len(data) and len(subchunks) < 10:
         subchunk_id = data[pos:pos + 4]
         subchunk_size = struct.unpack_from('<I', data[pos + 4:pos + 8])[0]
         subchunks.append(WavSubChunk(subchunk_id, pos, subchunk_size))

test/test.py

@@ -1106,6 +1106,7 @@ class NoConverterTests(unittest.TestCase):
     def setUp(self):
         self.wave_file = os.path.join(data_dir, 'test1.wav')
         self.wave24_file = os.path.join(data_dir, 'test1-24bit.wav')
+        self.wave_empty = os.path.join(data_dir, 'test1_empty.wav')
         self.mp3_file = os.path.join(data_dir, 'test1.mp3')
         self.raw_file = os.path.join(data_dir, 'test1.raw')
         AudioSegment.converter = "definitely-not-a-path-to-anything-asdjklqwop"
@@ -1195,6 +1196,19 @@ def test_exporting(self):
 
         self.assertEqual(len(exported), len(seg))
 
+    def test_opening_empty_wav_file(self):
+        seg = AudioSegment.from_wav(self.wave_empty)
+        self.assertTrue(len(seg) == 0)
+
+        seg = AudioSegment.from_file(self.wave_empty)
+        self.assertTrue(len(seg) == 0)
+
+        seg = AudioSegment.from_file(self.wave_empty, "wav")
+        self.assertTrue(len(seg) == 0)
+
+        seg = AudioSegment.from_file(self.wave_empty, format="wav")
+        self.assertTrue(len(seg) == 0)
+
 
 class FilterTests(unittest.TestCase):