Shutdown dmypy after a configurable timeout

We call `dmypy run` with the `--timeout` option so that the daemon will
shut down automatically after specified delay of inactivity. The timeout
value is configurable through `dmypy_timeout` option, it defaults to
60s.

Fix #88.

Author: dlax

README.rst

@@ -60,6 +60,11 @@ Configuration
      - ``string``
      - **Specifies which status file dmypy should use**. This modifies the ``--status-file`` option passed to ``dmypy`` given ``dmypy`` is active.
      - ``.dmypy.json``
+   * - ``dmypy_timeout``
+     - ``pylsp.plugins.pylsp_mypy.dmypy_timeout``
+     - ``string``
+     - **Specifies the inactivity timeout after which the mypy daemon will automatically shut down**.
+     - ``60``
    * - ``config_sub_paths``
      - ``pylsp.plugins.pylsp_mypy.config_sub_paths``
      - ``array`` of ``string`` items

pylsp_mypy/plugin.py

@@ -293,6 +293,7 @@ def get_diagnostics(
 
     if dmypy:
         dmypy_status_file = settings.get("dmypy_status_file", ".dmypy.json")
+        dmypy_timeout = int(settings.get("dmypy_timeout", 60))
 
     args = ["--show-error-end", "--no-error-summary", "--no-pretty"]
 
@@ -398,7 +399,14 @@ def get_diagnostics(
                 mypy_api.run_dmypy(["--status-file", dmypy_status_file, "restart"])
 
         # run to use existing daemon or restart if required
-        args = ["--status-file", dmypy_status_file, "run", "--"] + apply_overrides(args, overrides)
+        args = [
+            "--status-file",
+            dmypy_status_file,
+            "run",
+            "--timeout",
+            str(dmypy_timeout),
+            "--",
+        ] + apply_overrides(args, overrides)
         if dmypy_command:
             # dmypy exists on PATH or was provided by settings
             # -> use this dmypy