python type_error ai_generated true

断言错误：期望调用：mock_function(1, 2, 3) 实际调用：mock_function(1, 2, 4)

AssertionError: Expected call: mock_function(1, 2, 3) Actual call: mock_function(1, 2, 4)

ID: python/unittest-mock-assert-called-with-argument-mismatch

其他格式: JSON · Markdown 中文 · English
80%修复率
88%置信度
0证据数
2024-01-20首次发现

版本兼容性

版本状态引入弃用备注
3.8 active — — —
3.9 active — — —
3.10 active — — —

根因分析

模拟对象被调用时使用的参数与assert_called_with等断言方法中指定的预期参数不匹配，通常是由于被测代码中的数据或逻辑略有差异。

English

The mock object was called with arguments that do not match the expected arguments specified in assert_called_with or similar assertion methods, often due to a slight difference in data or logic in the code under test.

generic

解决方案

  1. 90% 成功率 Debug the code under test to understand why arguments differ, then adjust the test or fix the code 
    Add print statements or use a debugger to inspect the actual arguments passed to the mock. For example: mock_function.assert_called_with(1, 2, 3) but if it fails, check the actual call via mock_function.call_args.
  2. 80% 成功率 Use `assert_called_once_with` with flexible matchers like `unittest.mock.ANY` or custom matchers for acceptable variations 
    from unittest.mock import ANY
mock_function.assert_called_once_with(1, 2, ANY)
This allows the third argument to be anything, but still verifies the first two.

无效尝试

常见但无效的做法:

  1. Changing the expected arguments to match the actual call without investigating why the code under test produces different values 70% 失败

    This masks the real issue in the code under test, potentially allowing bugs to go undetected.

  2. Using `assert_any_call` instead of `assert_called_with` to ignore argument differences 50% 失败

    This weakens the test by not verifying the exact arguments, which may hide important regressions.