Fix hang due to missing clean-up in exception path

Must close and free before raising the error here.

tiledb/libtiledb.pyx

@@ -3405,6 +3405,7 @@ cdef class Array(object):
         cdef uint64_t _timestamp = 0
         if timestamp is not None:
             _timestamp = <uint64_t> timestamp
+
         # allocate and then open the array
         cdef tiledb_array_t* array_ptr = NULL
         cdef int rc = TILEDB_OK
@@ -3431,9 +3432,12 @@ cdef class Array(object):
 
         # view on a single attribute
         if attr and not any(attr == schema.attr(i).name for i in range(schema.nattr)):
+            tiledb_array_close(ctx_ptr, array_ptr)
+            tiledb_array_free(&array_ptr)
             raise KeyError("No attribute matching '{}'".format(attr))
         else:
             self.view_attr = unicode(attr) if (attr is not None) else None
+
         self.ctx = ctx
         self.uri = unicode(uri)
         self.mode = unicode(mode)

tiledb/tests/test_libtiledb.py

@@ -1610,7 +1610,7 @@ def test_view_multiattr(self):
             T[:] = {'': anon_ar, 'named': named_ar}
 
         with self.assertRaises(KeyError):
-            T = tiledb.DenseArray(uri, 'r', attr="foo111")
+            T = tiledb.DenseArray(uri, 'r', attr="foo111", ctx=ctx)
 
         with tiledb.DenseArray(uri, 'r', attr="named", ctx=ctx) as T:
             assert_array_equal(T, named_ar)