python runtime_error ai_generated true

AttributeError: 'CaptureFixture' object has no attribute 'readouterr'

ID: python/pytest-capture-no-output

Also available as: JSON · Markdown · 中文
80%Fix Rate
88%Confidence
0Evidence
2024-11-09First Seen

Version Compatibility

VersionStatusIntroducedDeprecatedNotes
7.x active — — —
8.x active — — —

Root Cause

In newer pytest versions, `capsys` returns a `CaptureFixture` object and the method to read output is `readouterr()`. In some versions a typo like `read_outerr` or using `capfd` incorrectly causes this.

generic

中文

在新版 pytest 中，`capsys` 返回 `CaptureFixture` 对象，读取输出的方法为 `readouterr()`。拼写错误（如 `read_outerr`）或误用 `capfd` 会导致此错误。

Workarounds

  1. 97% success 
    Use the correct method:
def test_out(capsys):
    print('hi')
    captured = capsys.readouterr()
    assert captured.out == 'hi\n'

Dead Ends

Common approaches that don't work:

  1. 80% fail

    These methods don't exist on CaptureFixture.

  2. 70% fail

    Same API surface; typo persists.