Add instructions on how to run locally and in neovim

NEOVIM_SETUP.md

@@ -0,0 +1,100 @@
+# Using GitHub Actions Language Server in Neovim
+
+## Prerequisites
+
+- Node.js 18+
+- Neovim 0.11+ with the new LSP config format
+
+## Setup
+
+### 1. Clone and build
+
+```bash
+git clone https://github.com/actions/languageservices.git
+cd languageservices
+npm install
+npm run build --workspaces --if-present
+```
+
+### 2. Bundle the server
+
+The server needs to be bundled into a single file to avoid ESM module resolution issues:
+
+```bash
+cd languageserver
+npx esbuild src/index.ts \
+  --bundle \
+  --platform=node \
+  --target=node18 \
+  --format=cjs \
+  --outfile=dist/server-bundled.cjs \
+  --external:vscode \
+  --loader:.json=json
+```
+
+This creates `dist/server-bundled.cjs` (~5.6MB) that contains the entire server.
+
+### 3. Configure Neovim
+
+Create `~/.config/nvim/lsp/actionsls.lua`:
+
+```lua
+return {
+  cmd = {
+    "/absolute/path/to/languageservices/languageserver/bin/actions-languageserver",
+  },
+  filetypes = { "yaml" },
+  root_markers = { ".git" },
+  init_options = {
+    sessionToken = os.getenv("GITHUB_SESSION_TOKEN") or "",
+    logLevel = "info",
+  },
+}
+```
+
+**Important:** Replace `/absolute/path/to/languageservices` with your actual clone path.
+
+### 4. Enable the LSP in your init.lua
+
+Add to your Neovim configuration:
+
+```lua
+vim.lsp.enable('actionsls')
+```
+
+### 5. Restart Neovim
+
+Open any `.github/workflows/*.yml` file and the language server should attach automatically.
+
+## Files Created
+
+- `languageserver/dist/server-bundled.cjs` - Bundled server (~5.6MB)
+- `languageserver/bin/actions-languageserver` - Shell wrapper script
+
+The `dist/` directory is gitignored; you'll need to rebuild after pulling updates.
+
+## Troubleshooting
+
+Check if the server is running:
+
+```vim
+:lua =vim.lsp.get_clients()
+```
+
+View LSP logs:
+
+```bash
+tail -f ~/.local/state/nvim/lsp.log
+```
+
+Manually start the server to test:
+
+```vim
+:lua vim.lsp.start({name='actionsls', cmd={'/path/to/bin/actions-languageserver'}, root_dir=vim.fn.getcwd(), init_options={sessionToken='', logLevel='info'}})
+```
+
+## Notes
+
+- The main code change is in `languageserver/src/index.ts` to use dynamic imports, avoiding loading browser modules in Node.js
+- The bundling step is necessary because TypeScript outputs ESM with bare imports that Node.js can't resolve
+- Only workflow files in git repositories will activate the LSP (due to `root_markers = { ".git" }`)

languageserver/bin/actions-languageserver

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+#!/bin/bash
+# Wrapper script to start the Actions language server
+
+DIR="$(cd "$(dirname "$0")" && pwd)"
+
+exec node "$DIR/../dist/server-bundled.cjs" --stdio "$@"

languageserver/src/index.ts

@@ -1,26 +1,22 @@
-import {Connection} from "vscode-languageserver";
-import {
-  BrowserMessageReader,
-  BrowserMessageWriter,
-  createConnection as createBrowserConnection
-} from "vscode-languageserver/browser";
-import {createConnection as createNodeConnection} from "vscode-languageserver/node";
+import { Connection } from "vscode-languageserver";
 
-import {initConnection} from "./connection";
+import { initConnection } from "./connection.js";
 
 /** Helper function determining whether we are executing with node runtime */
 function isNode(): boolean {
   return typeof process !== "undefined" && process.versions?.node != null;
 }
 
-function getConnection(): Connection {
+async function getConnection(): Promise<Connection> {
   if (isNode()) {
-    return createNodeConnection();
+    const { createConnection } = await import("vscode-languageserver/node.js");
+    return createConnection();
   } else {
+    const { BrowserMessageReader, BrowserMessageWriter, createConnection } = await import("vscode-languageserver/browser.js");
     const messageReader = new BrowserMessageReader(self);
     const messageWriter = new BrowserMessageWriter(self);
-    return createBrowserConnection(messageReader, messageWriter);
+    return createConnection(messageReader, messageWriter);
   }
 }
 
-initConnection(getConnection());
+getConnection().then(initConnection);