pw_ide: Allow disabling clangd query drivers arg

Change-Id: I9b6075217561f3556f27e5dc45ee7b373235bd15
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/233491
Reviewed-by: Anthony DiGirolamo <[email protected]>
Pigweed-Auto-Submit: Chad Norvell <[email protected]>
Commit-Queue: Auto-Submit <[email protected]>
Lint: Lint 🤖 <[email protected]>

pw_ide/py/pw_ide/cpp.py

@@ -1202,13 +1202,18 @@ def __init__(self, settings: PigweedIdeSettings):
             compile_commands_dir = str(state.stable_target_link)
 
         host_cc_path = find_cipd_installed_exe_path("clang++")
+
         self.arguments: list[str] = [
             f'--compile-commands-dir={compile_commands_dir}',
-            f'--query-driver={settings.clangd_query_driver_str(host_cc_path)}',
             '--background-index',
             '--clang-tidy',
         ]
 
+        query_driver = settings.clangd_query_driver_str(host_cc_path)
+
+        if query_driver is not None:
+            self.arguments.append(f'--query-driver={query_driver}')
+
     def command(self, system: str = platform.system()) -> str:
         """Return the command that runs clangd with Pigweed paths."""
 

pw_ide/py/pw_ide/settings.py

@@ -332,17 +332,25 @@ def clangd_alternate_path(self) -> Path | None:
         return self._config.get('clangd_alternate_path', None)
 
     @property
-    def clangd_additional_query_drivers(self) -> list[str]:
+    def clangd_additional_query_drivers(self) -> list[str] | None:
         """Additional query driver paths that clangd should use.
 
         By default, ``pw_ide`` supplies driver paths for the toolchains included
         in Pigweed. If you are using toolchains that are not supplied by
         Pigweed, you should include path globs to your toolchains here. These
         paths will be given higher priority than the Pigweed toolchain paths.
+
+        If you want to omit the query drivers argument altogether, set this to
+        ``null``.
         """
         return self._config.get('clangd_additional_query_drivers', list())
 
-    def clangd_query_drivers(self, host_clang_cc_path: Path) -> list[str]:
+    def clangd_query_drivers(
+        self, host_clang_cc_path: Path
+    ) -> list[str] | None:
+        if self.clangd_additional_query_drivers is None:
+            return None
+
         drivers = [
             *[
                 _expand_any_vars_str(p)
@@ -357,8 +365,13 @@ def clangd_query_drivers(self, host_clang_cc_path: Path) -> list[str]:
 
         return drivers
 
-    def clangd_query_driver_str(self, host_clang_cc_path: Path) -> str:
-        return ','.join(self.clangd_query_drivers(host_clang_cc_path))
+    def clangd_query_driver_str(self, host_clang_cc_path: Path) -> str | None:
+        clangd_query_drivers = self.clangd_query_drivers(host_clang_cc_path)
+
+        if clangd_query_drivers is None:
+            return None
+
+        return ','.join(clangd_query_drivers)
 
     @property
     def workspace_root(self) -> Path: