io/msgpack: Raise a more informative exception on file not found

Author: Sam Spilsbury

pandas/io/packers.py

@@ -184,6 +184,8 @@ def read(fh):
         if exists:
             with open(path_or_buf, 'rb') as fh:
                 return read(fh)
+        else:
+            return FileNotFoundError('{} not found'.format(path_or_buf))
 
     if isinstance(path_or_buf, bytes):
         # treat as a binary-like

pandas/tests/io/test_packers.py

@@ -934,3 +934,7 @@ def test_msgpack_period_freq(self):
         s = Series(np.random.rand(5), index=date_range('20130101', periods=5))
         r = read_msgpack(s.to_msgpack())
         repr(r)
+
+    def test_msgpack_file_not_found(self):
+        bad_path = '1/2/3/4/path/does/not/exist'
+        pytest.raises(read_msgpack, FileNotFoundError, bad_path)