feat(language-server): standalone Malloy LSP with render-tag diagnostics

package.json

@@ -23,6 +23,7 @@
       "packages/malloy-render",
       "packages/malloy-render-validator",
       "packages/malloy-syntax-highlight",
+      "packages/malloy-language-server",
       "test",
       "profiler"
     ]

packages/malloy-language-server/bin/malloy-language-server.js

@@ -0,0 +1,79 @@
+#!/usr/bin/env node
+
+/*
+ * Copyright Contributors to the Malloy project
+ * SPDX-License-Identifier: MIT
+ */
+
+const args = process.argv.slice(2);
+
+if (args[0] === 'check') {
+  // One-shot diagnostic mode
+  const files = [];
+  let format = 'text';
+  let globalConfigDir;
+
+  for (let i = 1; i < args.length; i++) {
+    if (args[i] === '--format' && args[i + 1]) {
+      format = args[i + 1];
+      i++;
+    } else if (args[i] === '--global-config-dir' && args[i + 1]) {
+      globalConfigDir = args[i + 1];
+      i++;
+    } else if (!args[i].startsWith('-')) {
+      files.push(args[i]);
+    }
+  }
+
+  if (files.length === 0) {
+    console.error('Usage: malloy-language-server check <file.malloy> [file2.malloy ...] [--format text|json] [--global-config-dir <path>]');
+    process.exit(1);
+  }
+
+  const {check} = require('../dist/check');
+  check(files, {format, globalConfigDir}).then((exitCode) => {
+    process.exit(exitCode);
+  }).catch((err) => {
+    console.error(err);
+    process.exit(1);
+  });
+} else {
+  // Long-lived LSP server mode (stdio)
+  const {createConnection, ProposedFeatures} = require('vscode-languageserver/node');
+  const {createServer, CommonConnectionManager, NodeURLReader} = require('../dist/index');
+  const os = require('os');
+  const {pathToFileURL} = require('url');
+
+  // Try to load backends (optional)
+  try { require('@malloydata/malloy-connections'); } catch {}
+  try { require('@malloydata/db-publisher'); } catch {}
+
+  const {ConnectionFactory} = require('../dist/common/connections/types');
+
+  const connection = createConnection(ProposedFeatures.all);
+  const urlReader = new NodeURLReader();
+  const connectionManager = new CommonConnectionManager(
+    {}, // Empty factory — backends registered via side-effect imports above
+    {
+      expandHome: (path) => path.replace(/^~/, os.homedir()),
+      pathToFileURL: (path) => pathToFileURL(path),
+    }
+  );
+  connectionManager.setURLReader(urlReader);
+
+  // Parse optional flags
+  let globalConfigDir;
+  for (let i = 0; i < args.length; i++) {
+    if (args[i] === '--global-config-dir' && args[i + 1]) {
+      globalConfigDir = args[i + 1];
+      i++;
+    }
+  }
+  if (globalConfigDir) {
+    connectionManager.setGlobalConfigDirectory(globalConfigDir);
+  } else if (process.env['MALLOY_GLOBAL_CONFIG_DIR']) {
+    connectionManager.setGlobalConfigDirectory(process.env['MALLOY_GLOBAL_CONFIG_DIR']);
+  }
+
+  createServer(connection, connectionManager, {urlReader});
+}

packages/malloy-language-server/claude-code-plugin/.claude-plugin/plugin.json

@@ -0,0 +1,8 @@
+{
+  "name": "malloy-lsp",
+  "version": "1.0.0",
+  "description": "Malloy language intelligence for Claude Code — diagnostics, completions, hover, go-to-definition for .malloy files",
+  "author": {"name": "Malloy Contributors"},
+  "repository": "https://github.com/malloydata/malloy",
+  "keywords": ["malloy", "lsp", "data", "sql"]
+}

packages/malloy-language-server/claude-code-plugin/.lsp.json

@@ -0,0 +1,10 @@
+{
+  "malloy": {
+    "command": "malloy-language-server",
+    "extensionToLanguage": {
+      ".malloy": "malloy",
+      ".malloysql": "malloy-sql",
+      ".malloynb": "malloy-notebook"
+    }
+  }
+}

packages/malloy-language-server/package.json

@@ -0,0 +1,55 @@
+{
+  "name": "@malloydata/malloy-language-server",
+  "version": "0.0.396",
+  "license": "MIT",
+  "description": "Malloy Language Server Protocol implementation — diagnostics, completions, hover, go-to-definition for .malloy files",
+  "main": "./dist/index.js",
+  "types": "./dist/index.d.ts",
+  "bin": {
+    "malloy-language-server": "./bin/malloy-language-server.js"
+  },
+  "exports": {
+    ".": {
+      "types": "./dist/index.d.ts",
+      "default": "./dist/index.js"
+    },
+    "./node": {
+      "types": "./dist/node/index.d.ts",
+      "default": "./dist/node/index.js"
+    },
+    "./package.json": "./package.json"
+  },
+  "typesVersions": {
+    "*": {
+      "index": ["./dist/index.d.ts"],
+      "node": ["./dist/node/index.d.ts"]
+    }
+  },
+  "engines": {
+    "node": ">=20"
+  },
+  "homepage": "https://github.com/malloydata/malloy#readme",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/malloydata/malloy"
+  },
+  "scripts": {
+    "build": "tsc --build",
+    "clean": "tsc --build --clean && rm -f tsconfig.tsbuildinfo"
+  },
+  "dependencies": {
+    "@malloydata/malloy": "0.0.396",
+    "@malloydata/malloy-sql": "0.0.396",
+    "@malloydata/malloy-interfaces": "0.0.396",
+    "@malloydata/render-validator": "0.0.396",
+    "vscode-languageserver": "^9.0.1",
+    "vscode-languageserver-textdocument": "^1.0.8",
+    "vscode-jsonrpc": "^8.1.0",
+    "vscode-uri": "^3.0.7",
+    "lodash": "^4.17.21"
+  },
+  "optionalDependencies": {
+    "@malloydata/malloy-connections": "0.0.396",
+    "@malloydata/db-publisher": "0.0.396"
+  }
+}