VSCode集成测试与mypy配置冲突问题求助

我们偏好VSCode集成测试工具，同时也青睐mypy，但二者无法兼容。当我们在pytest.ini中添加mypy参数，配置如下：

[pytest]
pythonpath=./src
addopts = -vvv --cov --cov-report=term-missing --cov-fail-under=100 --ignore=.vscode --mypy 
filterwarnings =
    ignore:.*pkg_resources.*:DeprecationWarning

集成测试视图会丢失——移除--mypy参数后一切正常，但添加该参数后，仅能看到一个setup.py测试（如图所示）。

在扩展主机输出中，我们发现了“Illegal argument: line must be non-negative”错误：

2023-12-21 17:15:52.561 [error] Error: Illegal argument: line must be non-negative
    at m (/Applications/Visual Studio Code.app/Contents/Resources/app/out/vs/workbench/api/node/extensionHostProcess.js:10:1101)
    at new f (/Applications/Visual Studio Code.app/Contents/Resources/app/out/vs/workbench/api/node/extensionHostProcess.js:137:4467)
    at forEach (/Users/samjoseph/.vscode/extensions/ms-python.python-2023.22.1/src/client/testing/testController/common/utils.ts:159:50)
    at Array.forEach (<anonymous>)
    at populateTestTree (/Users/samjoseph/.vscode/extensions/ms-python.python-2023.22.1/src/client/testing/testController/common/utils.ts:154:27)
    at forEach (/Users/samjoseph/.vscode/extensions/ms-python.python-2023.22.1/src/client/testing/testController/common/utils.ts:176:17)
    at Array.forEach (<anonymous>)
    at populateTestTree (/Users/samjoseph/.vscode/extensions/ms-python.python-2023.22.1/src/client/testing/testController/common/utils.ts:154:27)
    at forEach (/Users/samjoseph/.vscode/extensions/ms-python.python-2023.22.1/src/client/testing/testController/common/utils.ts:176:17)
    at Array.forEach (<anonymous>)
    at populateTestTree (/Users/samjoseph/.vscode/extensions/ms-python.python-2023.22.1/src/client/testing/testController/common/utils.ts:154:27)
    at t.PythonResultResolver._resolveDiscovery (/Users/samjoseph/.vscode/extensions/ms-python.python-2023.22.1/src/client/testing/testController/common/resultResolver.ts:60:25)
    at t.PythonResultResolver.resolveDiscovery (/Users/samjoseph/.vscode/extensions/ms-python.python-2023.22.1/src/client/testing/testController/common/resultResolver.ts:35:21)
    at f.value (/Users/samjoseph/.vscode/extensions/ms-python.python-2023.22.1/src/client/testing/testController/pytest/pytestDiscoveryAdapter.ts:22:80)
    at n.y (/Applications/Visual Studio Code.app/Contents/Resources/app/out/vs/workbench/api/node/extensionHostProcess.js:80:1902)
    at n.fire (/Applications/Visual Studio Code.app/Contents/Resources/app/out/vs/workbench/api/node/extensionHostProcess.js:80:2119)
    at t.PythonTestServer._fireDataReceived (/Users/samjoseph/.vscode/extensions/ms-python.python-2023.22.1/src/client/testing/testController/common/server.ts:83:43)
    at t.PythonTestServer._resolveData (/Users/samjoseph/.vscode/extensions/ms-python.python-2023.22.1/src/client/testing/testController/common/server.ts:65:22)
    at Socket.<anonymous> (/Users/samjoseph/.vscode/extensions/ms-python.python-2023.22.1/src/client/testing/testController/common/server.ts:28:54)
    at Socket.emit (node:events:513:28)
    at addChunk (node:internal/streams/readable:324:12)
    at readableAddChunk (node:internal/streams/readable:297:9)
    at Socket.Readable.push (node:internal/streams/readable:234:10)
    at TCP.onStreamRead (node:internal/stream_base_commons:190:23)

解决思路： #

• 拆分mypy检查与测试发现流程：不要在pytest.ini的addopts中全局添加--mypy，而是单独运行mypy检查。比如在VSCode中配置自定义任务（.vscode/tasks.json）执行mypy：

  {
      "version": "2.0.0",
      "tasks": [
          {
              "label": "mypy: 类型检查",
              "type": "shell",
              "command": "${config:python.pythonPath} -m mypy ./src",
              "problemMatcher": ["$mypy"],
              "group": "build"
          }
      ]
  }
  

  需要时手动运行该任务，或设置为保存时自动触发。

• 限制pytest-mypy的检查范围：在pytest.ini中添加mypy专属配置，排除setup.py或不需要检查的文件，避免生成无效测试项干扰VSCode测试视图：

  [pytest]
  pythonpath=./src
  addopts = -vvv --cov --cov-report=term-missing --cov-fail-under=100 --ignore=.vscode
  filterwarnings =
      ignore:.*pkg_resources.*:DeprecationWarning
  
  [mypy]
  pythonpath = ./src
  exclude = setup.py
  

  这样即使保留--mypy参数，pytest-mypy也不会处理setup.py，也就不会生成导致VSCode解析出错的测试项。

• 更新相关组件版本：把VSCode的Python扩展（ms-python.python）和pytest-mypy插件更新到最新版，这类兼容性问题通常会在后续版本中被修复：

  • 在VSCode扩展面板找到Python扩展点击更新
  • 终端执行pip install --upgrade pytest-mypy更新插件

• 临时规避方案：如果必须在测试命令中保留--mypy，可以在VSCode设置中禁用测试视图的自动发现，改用终端手动运行pytest命令，或调整测试发现参数跳过mypy相关测试项。

内容的提问来源于stack exchange，提问作者Sam Joseph