allow passing node opts to pyright process launch info

Author: Mazyod

lsp_types/pyright/backend.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 import json
+import shutil
 from pathlib import Path
 
 import lsp_types
@@ -14,6 +15,17 @@
 class PyrightBackend(LSPBackend):
     """Pyright-specific LSP backend implementation"""
 
+    def __init__(self, *, node_flags: list[str] | None = None):
+        """
+        Initialize PyrightBackend.
+
+        Args:
+            node_flags: Optional list of node flags to pass when launching the server.
+                       If provided, pyright-langserver will be launched via node with these flags.
+                       Example: ['--prof'] for profiling, ['--cpu-prof'] for CPU profiling.
+        """
+        self._node_flags = node_flags or []
+
     def write_config(self, base_path: Path, options: PyrightConfig) -> None:
         """Write pyrightconfig.json configuration file"""
         config_path = base_path / "pyrightconfig.json"
@@ -24,7 +36,20 @@ def create_process_launch_info(
     ) -> ProcessLaunchInfo:
         """Create process launch info for Pyright LSP server"""
         # NOTE: requires node and basedpyright to be installed and accessible
-        return ProcessLaunchInfo(cmd=["pyright-langserver", "--stdio"], cwd=base_path)
+        if self._node_flags:
+            # Launch via node with specified flags
+            langserver_path = shutil.which("pyright-langserver")
+            if not langserver_path:
+                raise RuntimeError(
+                    "pyright-langserver not found in PATH. "
+                    "Please ensure it is installed and accessible."
+                )
+            cmd = ["node", *self._node_flags, langserver_path, "--stdio"]
+        else:
+            # Direct invocation (default behavior)
+            cmd = ["pyright-langserver", "--stdio"]
+
+        return ProcessLaunchInfo(cmd=cmd, cwd=base_path)
 
     def get_lsp_capabilities(self) -> types.ClientCapabilities:
         """Get LSP client capabilities for Pyright"""