dmypy server always restart when using --shadow-file

Bug Report

dmypy server restart if an option is changed, while it makes sense for most options, I don't think it make sense for --shadow-file.

If the sources to check used temporary files and --shadow-file to help mypy to understand where this temporary file comes.
dmypy server restart on each dmypy run because of the temporary file name change or the source to check change.

Expected Behavior

dmypy ignores --shadow-file when it compares Options.snapshot() between the client and the server. So mypy daemon stay warm.

Actual Behavior

dmypy server always returns {"restart": "configuration changed"} to the client and get retarted.

Your Environment

• Mypy version used: 0.920
• Mypy command-line flags: --shadow-file myfile.py tempfile myfile.py
• Python version used: python 3.10
• Operating system and version: arch

まず、dmypy run 中に dmypy が行う client と server の Options.snapshot() の比較を追跡し、--shadow-file の変更がどのように設定変更の応答を引き起こすかに注目します。 一時ファイル名またはソースパスを変更しても daemon が再起動されなくなり、それ以外のオプションの変更では引き続き再起動されることを確認します。