Merge pull request #1475 from thoraxe/feature/godot-gdscript-lsp

feat: add GDScript (Godot Engine) language server support

CHANGELOG.md

@@ -4,6 +4,7 @@ Status of the `main` branch. Changes prior to the next official version change w
 
 * Language Servers:
   - No longer store temporary files (e.g. downloads) in `~/solidlsp_tmp`; instead, use OS-specific temporary directories
+  - Add **GDScript** (Godot Engine) support. Serena connects over TCP to the Godot editor's built-in LSP server (port 6008, same for Godot 3 and 4) — no separate language server process to install. Godot major version is auto-detected from `config_version` in `project.godot`. Note: Godot's LSP does not implement `workspace/symbol`; first workspace-wide scans fall back to per-file requests and can be slow for large projects (results are cached to disk). See the [GDScript Setup Guide](https://oraios.github.io/serena/03-special-guides/godot_gdscript_setup_guide_for_serena.html) for details. Closes #1446.
 
 * Dashboard:
   - UI polish: switch UI font to Inter (with system fallbacks) and use JetBrains Mono only for code/logs/paths/identifiers; refine the light/dark palette with softer borders, clearer text hierarchy, and a more nuanced shadow/elevation system; introduce a consistent spacing scale; keep the orange accent.

README.md

@@ -110,7 +110,7 @@ Serena incorporates a powerful abstraction layer for the integration of language
 The underlying language servers are typically open-source projects or at least freely available for use.
 
 When using Serena's language server backend, we provide **support for over 40 programming languages**, including
-Ada / SPARK, AL, Angular, Ansible, Bash, BSL, C#, C/C++, Clojure, Crystal, Dart, Elixir, Elm, Erlang, Fortran, F#, GLSL, Go, Groovy, Haskell, Haxe, HLSL, HTML, Java, JavaScript, JSON, Julia, Kotlin, Lean 4, Lua, Luau, Markdown, MATLAB, mSL, Nix, OCaml, Perl, PHP, PowerShell, Python, R, Ruby, Rust, Scala, SCSS / Sass / CSS, Solidity, Swift, TOML, TypeScript, WGSL, YAML, and Zig.
+Ada / SPARK, AL, Angular, Ansible, Bash, BSL, C#, C/C++, Clojure, Crystal, Dart, Elixir, Elm, Erlang, Fortran, F#, GDScript, GLSL, Go, Groovy, Haskell, Haxe, HLSL, HTML, Java, JavaScript, JSON, Julia, Kotlin, Lean 4, Lua, Luau, Markdown, MATLAB, mSL, Nix, OCaml, Perl, PHP, PowerShell, Python, R, Ruby, Rust, Scala, SCSS / Sass / CSS, Solidity, Swift, TOML, TypeScript, WGSL, YAML, and Zig.
 
 ### The Serena JetBrains Plugin
 

docs/01-about/020_programming-languages.md

@@ -71,6 +71,10 @@ Some languages require additional installations or setup steps, as noted.
   (requires [.NET v8.0+](https://dotnet.microsoft.com/en-us/download/dotnet); uses FsAutoComplete/Ionide, which is auto-installed; for Homebrew .NET on macOS, set DOTNET_ROOT in your environment)
 * **Fortran**   
   (requires installation of fortls: `pip install fortls`)
+* **GDScript** (Godot Engine)  
+  (requires the Godot editor to be running with its built-in LSP enabled — default on port 6008;
+  Serena connects over TCP and does not launch Godot itself;
+  see the [GDScript Setup Guide](../03-special-guides/godot_gdscript_setup_guide_for_serena) for details)
 * **Go**  
   (requires installation of `gopls`)
 * **Groovy**  

docs/02-usage/050_configuration.md

@@ -487,6 +487,27 @@ Supported settings:
 | `fsautocomplete_version` | `0.83.0` | Override the FsAutoComplete version Serena installs as a .NET tool. |
 
 
+#### GDScript (Godot Engine)
+
+Serena connects to the Godot editor's built-in LSP server over TCP. No separate process is launched.
+
+Supported settings:
+
+| Setting | Default | Description |
+|---|---|---|
+| `port` | `6008` | TCP port the running Godot editor listens on for LSP connections. |
+| `request_timeout` | `30.0` | Seconds to wait for a response from the Godot LSP server. |
+
+Example:
+
+```yaml
+ls_specific_settings:
+  gdscript:
+    port: 6008
+    request_timeout: 60.0
+```
+
+
 #### Go (`gopls`)
 
 Serena forwards `ls_specific_settings.go.gopls_settings` to `gopls` as LSP `initializationOptions` when the Go language server is started.

docs/03-special-guides/godot_gdscript_setup_guide_for_serena.md

@@ -0,0 +1,94 @@
+# GDScript (Godot Engine) Setup Guide for Serena
+
+This guide explains how to prepare a Godot project so that Serena can provide code intelligence for GDScript (`.gd`) files via Godot's built-in Language Server Protocol (LSP) support.
+
+Unlike most language servers, Serena does **not** launch a separate LSP process for GDScript. Instead, Serena connects over TCP to the LSP server that the Godot editor itself runs while it is open. This means the Godot editor must already be running with your project loaded before you start Serena.
+
+---
+## Prerequisites
+
+- Godot Engine 3.x or 4.x installed and available on your system.
+- A Godot project with a `project.godot` file at the project root.
+
+No additional language server needs to be installed — Godot ships with a built-in LSP server that is enabled by default.
+
+---
+## How It Works
+
+When a Godot project is open in the editor, the editor listens for LSP connections on **TCP port 6008** (the same default for both Godot 3 and Godot 4). Serena connects to this port and communicates using standard LSP Content-Length framing.
+
+Serena automatically detects which major version of Godot your project targets by reading the `config_version` field from `project.godot`:
+
+- `config_version` = 5 → Godot 4
+- `config_version` = 4 → Godot 3
+
+If `config_version` is not recognized (e.g. from a future Godot release), Serena logs a warning and still connects — both Godot 3 and Godot 4 use the same port.
+
+No additional configuration is needed for version detection.
+
+---
+## Setup Steps
+
+1. Open your Godot project in the Godot editor and allow it to finish loading.
+
+2. Verify that the built-in LSP is enabled (it is on by default):
+   - Go to **Editor → Editor Settings → Network → Language Server**
+   - Confirm **"Use Language Server"** is checked.
+   - Confirm the port is **6008** (the default).
+
+3. Add `gdscript` to the `languages` list in your project's Serena configuration:
+   ```yaml
+   # .serena/project.yml
+   languages:
+     - gdscript
+   ```
+
+4. Start Serena in your project root. Serena will connect to the already-running Godot editor automatically.
+
+---
+## Using Serena with GDScript
+
+- Serena recognizes `.gd` and `.gdscript` files. The language identifier used in LSP communication is `gdscript`.
+- The Godot editor must remain open for the entire Serena session. If the editor is closed, Serena will lose its connection and will need to be restarted once the editor is open again.
+- On first use, you may see a brief delay while Serena establishes the TCP connection and the editor indexes your project files — this is expected.
+
+---
+## Performance Note
+
+Godot's built-in LSP does not implement the `workspace/symbol` request (global symbol search across the whole project). As a result, when Serena performs a workspace-wide symbol search — for example, calling `find_symbol` without a `relative_path` — it must fall back to sending a `textDocument/documentSymbol` request for **every `.gd` file** in the project individually.
+
+For large projects, this initial full-project scan can take **30–60 seconds or more**.
+
+To mitigate this:
+
+- **Pass `relative_path` whenever possible.** Narrowing a search to a specific file or subdirectory avoids scanning the entire workspace.
+- **Let the first full scan complete.** Serena caches the results to disk after the initial scan. Subsequent Serena sessions will use the on-disk cache and start instantly.
+
+---
+## Known Limitations
+
+| Limitation | Detail |
+|---|---|
+| No `workspace/symbol` support | Godot's LSP does not implement this request. All symbol lookups fall back to per-file `documentSymbol` requests, making the first full-project scan slow. |
+| Editor must stay open | Serena requires the Godot editor to be running throughout the session. Closing the editor breaks the TCP connection; restart Serena after reopening the editor. |
+| Slower workspace operations | `find_symbol` and `find_references` across the whole workspace are slower than for languages whose LSP servers support native workspace-wide queries. |
+
+---
+## Advanced Configuration
+
+You can customize Serena's GDScript connection via `ls_specific_settings` in your `serena_config.yml` or `project.yml`:
+
+```yaml
+ls_specific_settings:
+  gdscript:
+    port: 6008         # TCP port the Godot editor listens on (default: 6008)
+    request_timeout: 30.0  # seconds to wait for an LSP response (default: 30.0)
+```
+
+These override the defaults only if explicitly set.
+
+---
+## Reference
+
+- Godot LSP documentation: [https://docs.godotengine.org/en/stable/tutorials/editor/external_editor.html](https://docs.godotengine.org/en/stable/tutorials/editor/external_editor.html)
+- GDScript language reference: [https://docs.godotengine.org/en/stable/tutorials/scripting/gdscript/](https://docs.godotengine.org/en/stable/tutorials/scripting/gdscript/)

src/solidlsp/language_servers/godot_language_server.py

@@ -0,0 +1,141 @@
+"""GDScript language server for Godot Engine projects.
+
+Connects to an already-running Godot editor via TCP on port 6008.
+Both Godot 3 and Godot 4 (tested through 4.6.x) use this port.
+
+The editor must be open with its built-in language server enabled (default).
+"""
+
+import logging
+import os
+import pathlib
+from collections.abc import Callable
+
+from solidlsp.ls import SolidLanguageServer
+from solidlsp.ls_config import LanguageServerConfig
+from solidlsp.ls_process import LanguageServerInterface, TCPConnectionInfo, TCPLanguageServer
+from solidlsp.lsp_protocol_handler.lsp_types import InitializeParams
+from solidlsp.lsp_protocol_handler.server import ProcessLaunchInfo, StringDict
+from solidlsp.settings import SolidLSPSettings
+
+log = logging.getLogger(__name__)
+
+# Maps config_version in project.godot to the Godot major version
+_CONFIG_VERSION_TO_GODOT_MAJOR: dict[int, int] = {4: 3, 5: 4}
+
+DEFAULT_GODOT_LS_PORT = 6008
+DEFAULT_GODOT_REQUEST_TIMEOUT = 30.0
+
+
+class GodotLanguageServer(SolidLanguageServer):
+    """GDScript language server that connects to a running Godot editor.
+
+    Both Godot 3 and Godot 4 expose an LSP server on TCP port 6008.
+    The Godot editor must already be running — this class connects to it
+    rather than launching it.
+
+    ls_specific_settings for ``gdscript``:
+        - ``port`` (int): TCP port the Godot editor's LSP listens on (default: 6008).
+        - ``request_timeout`` (float): seconds to wait for an LSP response (default: 30.0).
+    """
+
+    def __init__(self, config: LanguageServerConfig, repository_root_path: str, solidlsp_settings: SolidLSPSettings) -> None:
+        self._godot_version = self._detect_godot_version(repository_root_path)
+        if self._godot_version is not None:
+            log.info("Detected Godot version %d for project at %s", self._godot_version, repository_root_path)
+        else:
+            log.warning("Could not detect Godot version for project at %s", repository_root_path)
+
+        # Dummy ProcessLaunchInfo — _create_language_server_interface() ignores it
+        super().__init__(config, repository_root_path, ProcessLaunchInfo(cmd=""), "gdscript", solidlsp_settings)
+
+    @staticmethod
+    def _detect_godot_version(repo_path: str) -> int | None:
+        """Read project.godot to determine the major Godot version.
+
+        Returns None if detection fails or the config_version is unrecognized.
+        """
+        project_file = os.path.join(repo_path, "project.godot")
+        try:
+            with open(project_file, encoding="utf-8") as f:
+                for line in f:
+                    line = line.strip()
+                    if line.startswith("config_version="):
+                        config_version = int(line.split("=", 1)[1])
+                        return _CONFIG_VERSION_TO_GODOT_MAJOR.get(config_version)
+        except (FileNotFoundError, ValueError, OSError):
+            pass
+        return None
+
+    def _create_language_server_interface(
+        self,
+        process_launch_info: ProcessLaunchInfo,
+        logging_fn: Callable[[str, str, StringDict | str], None] | None,
+    ) -> LanguageServerInterface:
+        settings: dict = self._custom_settings or {}
+        port = settings.get("port", DEFAULT_GODOT_LS_PORT)
+        request_timeout = settings.get("request_timeout", DEFAULT_GODOT_REQUEST_TIMEOUT)
+        self._conn_info = TCPConnectionInfo(host="127.0.0.1", port=port)
+        return TCPLanguageServer(
+            connection_info=self._conn_info,
+            language=self.language,
+            determine_log_level=self._determine_log_level,
+            logger=logging_fn,
+            request_timeout=request_timeout,
+        )
+
+    @staticmethod
+    def _get_initialize_params(repository_absolute_path: str) -> InitializeParams:
+        root_uri = pathlib.Path(repository_absolute_path).as_uri()
+        params = {
+            "processId": os.getpid(),
+            "rootUri": root_uri,
+            "rootPath": repository_absolute_path,
+            "workspaceFolders": [{"uri": root_uri, "name": os.path.basename(repository_absolute_path)}],
+            "capabilities": {
+                "textDocument": {
+                    "synchronization": {"didSave": True, "dynamicRegistration": True},
+                    "definition": {"dynamicRegistration": True},
+                    "declaration": {"dynamicRegistration": True},
+                    "references": {"dynamicRegistration": True},
+                    "documentSymbol": {
+                        "dynamicRegistration": True,
+                        "hierarchicalDocumentSymbolSupport": True,
+                        "symbolKind": {"valueSet": list(range(1, 27))},
+                    },
+                    "completion": {
+                        "dynamicRegistration": True,
+                        "completionItem": {"snippetSupport": True},
+                    },
+                    "hover": {"dynamicRegistration": True, "contentFormat": ["markdown", "plaintext"]},
+                    "publishDiagnostics": {"relatedInformation": True},
+                },
+                "workspace": {
+                    "workspaceFolders": True,
+                    "didChangeConfiguration": {"dynamicRegistration": True},
+                },
+            },
+        }
+        return params  # type: ignore
+
+    def _start_server(self) -> None:
+        def do_nothing(params: dict) -> None:
+            return
+
+        # Godot sends this notification immediately on connect to report the open project path.
+        self.server.on_notification("gdscript_client/changeWorkspace", do_nothing)
+        # Godot-specific capability advertisement (not standard LSP).
+        self.server.on_notification("gdscript/capabilities", do_nothing)
+        self.server.on_notification("window/logMessage", lambda msg: log.info("LSP: window/logMessage: %s", msg))
+        self.server.on_notification("$/progress", do_nothing)
+        self.server.on_notification("textDocument/publishDiagnostics", do_nothing)
+        self.server.on_request("client/registerCapability", lambda params: None)
+
+        log.info("Connecting to Godot LSP at %s:%d", self._conn_info.host, self._conn_info.port)
+        self.server.start()
+
+        initialize_params = self._get_initialize_params(self.repository_root_path)
+        log.info("Sending LSP initialize request to Godot")
+        self.server.send.initialize(initialize_params)
+        self.server.notify.initialized({})
+        log.info("Godot LSP initialized")

src/solidlsp/ls_config.py

@@ -123,6 +123,12 @@ class Language(str, Enum):
     by the same server, since SPARK is distinguished by pragmas/aspects in
     source rather than by file extension.
     """
+    GDSCRIPT = "gdscript"
+    """GDScript language server for Godot Engine projects (Godot 3 and 4).
+    Connects to the Godot editor's built-in LSP server over TCP (port 6008).
+    The editor must already be running with its built-in LSP enabled (default).
+    Supports .gd and .gdscript files.
+    """
     # Experimental or deprecated Language Servers
     TYPESCRIPT_VTS = "typescript_vts"
     """Use the typescript language server through the natively bundled vscode extension via https://github.com/yioneko/vtsls"""
@@ -472,6 +478,8 @@ class Language(str, Enum):
                 return FilenameMatcher(".bsl", ".os")
             case self.ADA:
                 return FilenameMatcher(".ads", ".adb", ".ada", case_sensitive=False)
+            case self.GDSCRIPT:
+                return FilenameMatcher(".gd", ".gdscript")
             case self.HTML:
                 return FilenameMatcher(".html", ".htm")
             case self.SCSS:
@@ -727,6 +735,10 @@ class Language(str, Enum):
                 from solidlsp.language_servers.ada_language_server import AdaLanguageServer
 
                 return AdaLanguageServer
+            case self.GDSCRIPT:
+                from solidlsp.language_servers.godot_language_server import GodotLanguageServer
+
+                return GodotLanguageServer
             case self.HTML:
                 from solidlsp.language_servers.vscode_html_language_server import VsCodeHtmlLanguageServer
 

src/solidlsp/ls_process.py

@@ -3,6 +3,7 @@ import json
 import logging
 import os
 import platform
+import socket
 import subprocess
 import threading
 import time
@@ -620,3 +621,157 @@ class StdioLanguageServer(LanguageServerInterface):
                 # Log the error but don't raise to prevent cascading failures
                 log.error(f"Failed to write to stdin: {e}")
                 return
+
+
+@dataclass
+class TCPConnectionInfo:
+    """Connection parameters for an LSP server reachable over a TCP socket."""
+
+    host: str = "127.0.0.1"
+    port: int = 6008
+    connection_timeout: float = 30.0
+    retry_interval: float = 1.0
+
+
+class TCPLanguageServer(LanguageServerInterface):
+    """LanguageServerInterface that connects to an already-running LSP server over TCP.
+
+    Unlike :class:`StdioLanguageServer`, this class does not own the server process — it
+    connects to an externally-managed server (e.g. the Godot editor) and simply closes
+    the socket on stop. No LSP ``shutdown``/``exit`` sequence is sent, because the remote
+    server is expected to keep running after Serena disconnects.
+    """
+
+    def __init__(
+        self,
+        connection_info: TCPConnectionInfo,
+        language: Language,
+        determine_log_level: Callable[[str], int],
+        logger: Callable[[str, str, StringDict | str], None] | None = None,
+        request_timeout: float | None = None,
+    ) -> None:
+        super().__init__(language, determine_log_level, logger, request_timeout)
+        self._connection_info = connection_info
+        self._sock: socket.socket | None = None
+        self._file: Any = None  # socket.makefile("rb") - buffered reader
+        self._write_lock = threading.Lock()
+
+    def is_running(self) -> bool:
+        return self._sock is not None
+
+    def _start(self) -> None:
+        deadline = time.monotonic() + self._connection_info.connection_timeout
+        last_exc: Exception | None = None
+        while True:
+            try:
+                sock = socket.create_connection((self._connection_info.host, self._connection_info.port), timeout=5.0)
+                sock.settimeout(None)
+                self._sock = sock
+                self._file = sock.makefile("rb")
+                log.info("TCPLanguageServer connected to %s:%d", self._connection_info.host, self._connection_info.port)
+                break
+            except OSError as exc:
+                last_exc = exc
+                remaining = deadline - time.monotonic()
+                if remaining <= 0:
+                    raise RuntimeError(
+                        f"Could not connect to {self._connection_info.host}:{self._connection_info.port} "
+                        f"within {self._connection_info.connection_timeout}s"
+                    ) from last_exc
+                log.debug(
+                    "TCPLanguageServer: connection failed (%s), retrying in %.1fs (%.0fs left)",
+                    exc,
+                    self._connection_info.retry_interval,
+                    remaining,
+                )
+                time.sleep(min(self._connection_info.retry_interval, remaining))
+
+        threading.Thread(
+            target=self._read_loop,
+            name=f"LSP-tcp-reader:{self.language.value}",
+            daemon=True,
+        ).start()
+
+    def _stop(self, timeout: float) -> None:
+        # Close the socket first — this unblocks any readline() in the reader thread.
+        # BufferedReader.close() acquires an internal lock that readline() holds while
+        # blocked waiting for data; closing the socket first causes readline() to return
+        # with an error, releasing the lock before we call f.close().
+        sock = self._sock
+        self._sock = None
+        f = self._file
+        self._file = None
+        if sock:
+            try:
+                sock.shutdown(socket.SHUT_RDWR)
+            except Exception:
+                pass
+            try:
+                sock.close()
+            except Exception:
+                pass
+        if f:
+            try:
+                f.close()
+            except Exception:
+                pass
+
+    def _send_payload(self, payload: StringDict) -> None:
+        sock = self._sock
+        if sock is None:
+            return
+        self._trace("solidlsp", "ls", payload)
+        data = b"".join(create_message(payload))
+        with self._write_lock:
+            try:
+                sock.sendall(data)
+            except OSError as e:
+                log.error("Failed to write to TCP language server: %s", e)
+
+    def _read_loop(self) -> None:
+        """Read Content-Length-framed LSP messages from the TCP socket and dispatch them."""
+        exception: Exception | None = None
+        try:
+            while self._sock is not None:
+                f = self._file
+                if f is None:
+                    break
+                try:
+                    line = f.readline()
+                except OSError as exc:
+                    if not self._is_stopping:
+                        exception = LanguageServerTerminatedException("TCP read error", self.language, cause=exc)
+                    break
+                if not line:
+                    break
+                try:
+                    num_bytes = content_length(line)
+                except ValueError:
+                    continue
+                if num_bytes is None:
+                    continue
+                while line and line.strip():
+                    try:
+                        line = f.readline()
+                    except OSError:
+                        line = b""
+                        break
+                if not line:
+                    continue
+                try:
+                    body = f.read(num_bytes)
+                except OSError as exc:
+                    if not self._is_stopping:
+                        exception = LanguageServerTerminatedException("TCP read error", self.language, cause=exc)
+                    break
+                if len(body) < num_bytes:
+                    break
+                self._handle_body(body)
+        except Exception as exc:
+            exception = LanguageServerTerminatedException("Unexpected error in TCP language server read loop", self.language, cause=exc)
+        log.info("TCP language server read loop has terminated")
+        if not self._is_stopping:
+            if exception is None:
+                exception = LanguageServerTerminatedException("TCP language server read loop terminated unexpectedly", self.language)
+            log.error(str(exception))
+            self._cancel_pending_requests(exception)