python
runtime_error
ai_generated
true
AssertionError: assert {'a': 1, 'b': 2} == {'a': 1, 'b': 3} Omitting 1 identical items, use -vv to show Differing items:
ID: python/pytest-assertion-introspection-noqa
80%Fix Rate
87%Confidence
0Evidence
2024-04-15First Seen
Version Compatibility
| Version | Status | Introduced | Deprecated | Notes |
|---|---|---|---|---|
| 7.x | active | — | — | — |
| 8.x | active | — | — | — |
Root Cause
The assertion diff is truncated by default; developers think the diff is missing when actually -vv would show it. Sometimes the real bug is a type mismatch (1 vs '1').
generic中文
断言差异默认被截断;开发者认为差异缺失,实际上 -vv 会显示它。有时真正的错误是类型不匹配(1 与 '1')。
Workarounds
-
95% success
pytest -vv tests/test_x.py::test_dict
-
90% success
# pytest.ini [pytest] addopts = -vv --showlocals
Dead Ends
Common approaches that don't work:
-
70% fail
Adds noise; the real fix is enabling verbose diff.
-
75% fail
unittest diff is also truncated by default.
-
80% fail
Only shows the message, not the structured diff.