Mypy 错误：json.decoder.JSONDecodeError：未终止的字符串起始于：行 x 列 y（字符 z）

Question

我正在docker 容器中针对我的 django 项目运行mypy版本。0.910使用这个命令：

mypy --install-types --non-interactive --config-file=../setup.cfg "$@"

在过去的 6 个月左右的时间里，它一直运行良好，但有时会出现以下错误：

Traceback (most recent call last):
  File "/usr/local/bin/mypy", line 11, in <module>
    sys.exit(console_entry())
  File "/usr/local/lib/python3.6/dist-packages/mypy/__main__.py", line 11, in console_entry
    main(None, sys.stdout, sys.stderr)
  File "mypy/main.py", line 96, in main
  File "mypy/main.py", line 165, in run_build
  File "mypy/build.py", line 179, in build
  File "mypy/build.py", line 254, in _build
  File "mypy/build.py", line 2697, in dispatch
  File "mypy/build.py", line 3014, in process_graph
  File "mypy/build.py", line 3089, in process_fresh_modules
  File "mypy/build.py", line 1975, in load_tree
  File "/usr/lib/python3.6/json/__init__.py", line 354, in loads
    return _default_decoder.decode(s)
  File "/usr/lib/python3.6/json/decoder.py", line 339, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/lib/python3.6/json/decoder.py", line 355, in raw_decode
    obj, end = self.scan_once(s, idx)
json.decoder.JSONDecodeError: Unterminated string starting at: line 1 column 4925 (char 4924)
ERROR: 1

我所能做的就是完全重建容器来解决这个问题。难道是我配置错误了？

Answer 1

Mypy 默认情况下以增量模式工作，并带有存储在其中的缓存.mypy_cache（https://mypy.readthedocs.io/en/stable/command_line.html#incremental-mode），至少在我的情况下，发生这个问题是因为缓存是破碎的。

rm -rf .mypy_cache为我解决了这个问题。