Get rid of _bytes_read. Add test with seek(0)

Author: YuriiMotov

src/fastapi_cloud_cli/utils/progress_file.py

@@ -16,15 +16,13 @@ def __init__(
         self._progress_callback = progress_callback
         self._update_interval = update_interval
         self._last_update_time = 0.0
-        self._bytes_read = 0
 
     def read(self, n: int = -1) -> bytes:
         data = self._file.read(n)
-        self._bytes_read += len(data)
         now_ = datetime.now().timestamp()
         is_eof = (len(data) == 0) or (n > 0 and len(data) < n)
         if (now_ - self._last_update_time >= self._update_interval) or is_eof:
-            self._progress_callback(self._bytes_read)
+            self._progress_callback(self._file.tell())
             self._last_update_time = now_
         return data
 

tests/test_progress_file.py

@@ -105,6 +105,23 @@ def test_seek_and_tell() -> None:
     assert pf.tell() == 0
 
 
+def test_seek_resets_bytes_read() -> None:
+    file = _make_file(b"abcde")
+    mock_callback = Mock()
+
+    pf = ProgressFile(file, progress_callback=mock_callback)
+
+    pf.read(3)
+
+    # Imitate retrying
+    pf.seek(0)
+    pf.read(3)
+
+    pf.read(3)
+
+    mock_callback.assert_has_calls([call(3), call(5)])
+
+
 def test_iter_delegates() -> None:
     file = _make_file(b"line1\nline2\n")
     pf = ProgressFile(file, progress_callback=lambda _: None)