Add test for BytesIO objects

rhpvorderman · rhpvorderman · commit b3dd99850a1c · 2024-02-20T10:57:45.000+01:00
diff --git a/tests/test_xopen.py b/tests/test_xopen.py
@@ -588,3 +588,17 @@ def test_pass_file_object_for_writing(tmp_path, ext):
             f.write(first_line)
     with xopen(tmp_path / "out{ext}", "rb") as fh:
         assert fh.readline() == first_line
+
+
+@pytest.mark.parametrize("ext", extensions)
+def test_pass_bytesio_for_writing(ext):
+    filelike = io.BytesIO()
+    format = ext[1:]
+    if ext == ".zst" and zstandard is None:
+        return
+    first_line = CONTENT_LINES[0].encode("utf-8")
+    with xopen(filelike, "wb", format=format) as f:
+        f.write(first_line)
+    filelike.seek(0)
+    with xopen(filelike, "rb", format=format) as fh:
+        assert fh.readline() == first_line
