Improve quoting of arguments for subprocess executions

* Add util function subprocess_util.convert_shell_cmd
* Apply function in
  - StdioLanguageServer (replacing use of quote_arg function)
  - RuntimeDependencyCollection (previously no quoting applied)

CHANGELOG.md

@@ -9,6 +9,7 @@ Status of the `main` branch. Changes prior to the next official version change w
     at the Yarn-generated SDK.
   - `SvelteLanguageServer`: Fix diagnostics requests for TypeScript/JavaScript files incorrectly being
     processed by the Svelte LS instead of the TypeScript LS.
+  - Improve quoting of arguments in shell executions
 
 * Dashboard:
   - Make list of trusted hosts configurable, fixing host validation introduced in v1.5.2 allowing only

src/solidlsp/language_servers/common.py

@@ -10,7 +10,7 @@ from dataclasses import dataclass, replace
 from typing import Any, cast
 
 from solidlsp.ls_utils import FileUtils, PlatformUtils
-from solidlsp.util.subprocess_util import subprocess_kwargs
+from solidlsp.util import subprocess_util
 
 log = logging.getLogger(__name__)
 
@@ -101,18 +101,13 @@ class RuntimeDependencyCollection:
 
     @staticmethod
     def _run_command(command: str | list[str], cwd: str) -> None:
-        kwargs = subprocess_kwargs()
+        kwargs = subprocess_util.subprocess_kwargs()
         if not PlatformUtils.get_platform_id().is_windows():
             import pwd
 
             kwargs["user"] = pwd.getpwuid(os.getuid()).pw_name  # type: ignore
 
-        is_windows = platform.system() == "Windows"
-        if not isinstance(command, str) and not is_windows:
-            # Since we are using the shell, we need to convert the command list to a single string
-            # on Linux/macOS
-            command = " ".join(command)
-
+        command = subprocess_util.convert_shell_cmd(command)
         log.info("Running command %s in '%s'", f"'{command}'" if isinstance(command, str) else command, cwd)
 
         completed_process = subprocess.run(

src/solidlsp/ls_process.py

@@ -2,7 +2,6 @@ import asyncio
 import json
 import logging
 import os
-import platform
 import socket
 import subprocess
 import threading
@@ -33,7 +32,7 @@ from solidlsp.lsp_protocol_handler.server import (
     make_request,
     make_response,
 )
-from solidlsp.util.subprocess_util import quote_arg, subprocess_kwargs, terminate_process_tree_with_kill_fallback
+from solidlsp.util import subprocess_util
 
 log = logging.getLogger(__name__)
 
@@ -459,14 +458,9 @@ class StdioLanguageServer(LanguageServerInterface):
         child_proc_env = os.environ.copy()
         child_proc_env.update(self.process_launch_info.env)
 
-        cmd = self.process_launch_info.cmd
-        is_windows = platform.system() == "Windows"
-        if not isinstance(cmd, str) and not is_windows:
-            # Since we are using the shell, we need to convert the command list to a single string
-            # on Linux/macOS
-            cmd = " ".join(map(quote_arg, cmd))
+        cmd = subprocess_util.convert_shell_cmd(self.process_launch_info.cmd)
         log.info("Starting language server process via command: %s", self.process_launch_info.cmd)
-        kwargs = subprocess_kwargs()
+        kwargs = subprocess_util.subprocess_kwargs()
         kwargs["start_new_session"] = self.start_independent_lsp_process
         self.process = subprocess.Popen(
             cmd,
@@ -513,7 +507,9 @@ class StdioLanguageServer(LanguageServerInterface):
                 log.debug(f"Exception during graceful shutdown: {e}")
                 # Ignore errors here, we are proceeding to terminate anyway.
             # terminate the process
-            terminate_process_tree_with_kill_fallback(self.process, terminate_timeout=timeout, process_name=f"LS[{self.language.value}]")
+            subprocess_util.terminate_process_tree_with_kill_fallback(
+                self.process, terminate_timeout=timeout, process_name=f"LS[{self.language.value}]"
+            )
         finally:
             self.process = None
 

src/solidlsp/util/subprocess_util.py

@@ -19,19 +19,19 @@ def subprocess_kwargs() -> dict:
     return kwargs
 
 
-def quote_arg(arg: str) -> str:
+def convert_shell_cmd(cmd: str | list[str]) -> str | list[str]:
     """
-    Quotes a shell argument to prevent interpretation of metacharacters.
+    Converts a command (specified as a list or string) to a format supported by subprocess calls with shell=True on the current platform.
+    List format must be converted to string format on POSIX systems, quoting arguments appropriately,
+    while it can be used as-is on Windows.
 
-    Uses :func:`shlex.quote` on POSIX systems for proper escaping of all
-    shell-special characters. On Windows, wraps arguments containing spaces
-    in double quotes (Windows shell does not interpret single-quoted strings).
+    :param cmd: the command to convert, specified as a list of arguments
+    :return: a suitable representation of the command for subprocess calls on the current platform
     """
-    if platform.system() == "Windows":
-        if " " not in arg:
-            return arg
-        return f'"{arg}"'
-    return shlex.quote(arg)
+    if isinstance(cmd, list) and platform.system() != "Windows":
+        return " ".join(shlex.quote(arg) for arg in cmd)
+    else:
+        return cmd
 
 
 def _signal_process_tree(process: subprocess.Popen[bytes], terminate: bool = True) -> None: