feat(solidlsp): add ls_args and ls_extra_args for custom LS launch command

src/solidlsp/language_servers/clangd_language_server.py

@@ -28,6 +28,10 @@ class ClangdLanguageServer(SolidLanguageServer):
           ``compile_commands.json`` if needed.
         - clangd_version: Override the pinned Clangd version downloaded by Serena
           (default: the bundled Serena version).
+        - ls_extra_args: Extra arguments appended to the default clangd launch command
+          (e.g. ``["--query-driver=/usr/bin/arm-none-eabi-gcc"]``).
+        - ls_args: Fully replace the default clangd arguments (executable path is kept).
+          Use when you need complete control over the argument list.
     """
 
     def __init__(self, config: LanguageServerConfig, repository_root_path: str, solidlsp_settings: SolidLSPSettings):

src/solidlsp/ls.py

@@ -324,7 +324,12 @@ def create_launch_command(self) -> list[str]:
             core_path = path
         else:
             core_path = self._get_or_install_core_dependency()
-        return self._create_launch_command(core_path)
+        ls_args: list[str] | None = self._custom_settings.get("ls_args", None)
+        if ls_args is not None:
+            return [core_path] + ls_args
+        cmd = self._create_launch_command(core_path)
+        ls_extra_args: list[str] = self._custom_settings.get("ls_extra_args", [])
+        return cmd + ls_extra_args
 
     @abstractmethod
     def _create_launch_command(self, core_path: str) -> list[str]:

test/solidlsp/cpp/test_cpp_dependency_provider.py

@@ -0,0 +1,69 @@
+"""Tests for ClangdLanguageServer.DependencyProvider launch command construction."""
+
+from pathlib import Path
+from unittest.mock import patch
+
+import pytest
+
+from solidlsp.language_servers.clangd_language_server import ClangdLanguageServer
+from solidlsp.settings import SolidLSPSettings
+
+
+def _make_provider(
+    tmp_path: Path,
+    custom_settings: dict | None = None,
+) -> ClangdLanguageServer.DependencyProvider:
+    return ClangdLanguageServer.DependencyProvider(
+        custom_settings=SolidLSPSettings.CustomLSSettings(custom_settings or {}),
+        ls_resources_dir=str(tmp_path),
+    )
+
+
+@pytest.mark.cpp
+class TestClangdDependencyProvider:
+    def test_default_args(self, tmp_path: Path) -> None:
+        provider = _make_provider(tmp_path)
+        with patch.object(provider, "_get_or_install_core_dependency", return_value="/usr/bin/clangd"):
+            cmd = provider.create_launch_command()
+        assert cmd == ["/usr/bin/clangd", "--background-index"]
+
+    def test_ls_extra_args_appended_to_defaults(self, tmp_path: Path) -> None:
+        provider = _make_provider(tmp_path, {"ls_extra_args": ["--query-driver=/usr/bin/gcc", "--log=verbose"]})
+        with patch.object(provider, "_get_or_install_core_dependency", return_value="/usr/bin/clangd"):
+            cmd = provider.create_launch_command()
+        assert cmd == ["/usr/bin/clangd", "--background-index", "--query-driver=/usr/bin/gcc", "--log=verbose"]
+
+    def test_ls_args_replaces_default_args(self, tmp_path: Path) -> None:
+        provider = _make_provider(tmp_path, {"ls_args": ["--log=verbose"]})
+        with patch.object(provider, "_get_or_install_core_dependency", return_value="/usr/bin/clangd"):
+            cmd = provider.create_launch_command()
+        assert cmd == ["/usr/bin/clangd", "--log=verbose"]
+
+    def test_ls_args_empty_list_removes_all_default_args(self, tmp_path: Path) -> None:
+        provider = _make_provider(tmp_path, {"ls_args": []})
+        with patch.object(provider, "_get_or_install_core_dependency", return_value="/usr/bin/clangd"):
+            cmd = provider.create_launch_command()
+        assert cmd == ["/usr/bin/clangd"]
+
+    def test_ls_path_overrides_executable(self, tmp_path: Path) -> None:
+        provider = _make_provider(tmp_path, {"ls_path": "/custom/clangd"})
+        with patch.object(
+            provider,
+            "_get_or_install_core_dependency",
+            side_effect=AssertionError("should not be called when ls_path is set"),
+        ):
+            cmd = provider.create_launch_command()
+        assert cmd[0] == "/custom/clangd"
+        assert "--background-index" in cmd
+
+    def test_ls_path_with_ls_extra_args(self, tmp_path: Path) -> None:
+        provider = _make_provider(tmp_path, {"ls_path": "/custom/clangd", "ls_extra_args": ["--query-driver=/usr/bin/arm-gcc"]})
+        with patch.object(provider, "_get_or_install_core_dependency", side_effect=AssertionError("should not be called")):
+            cmd = provider.create_launch_command()
+        assert cmd == ["/custom/clangd", "--background-index", "--query-driver=/usr/bin/arm-gcc"]
+
+    def test_ls_path_with_ls_args(self, tmp_path: Path) -> None:
+        provider = _make_provider(tmp_path, {"ls_path": "/custom/clangd", "ls_args": ["--log=error"]})
+        with patch.object(provider, "_get_or_install_core_dependency", side_effect=AssertionError("should not be called")):
+            cmd = provider.create_launch_command()
+        assert cmd == ["/custom/clangd", "--log=error"]