Set up language server configuration automatically

Now, Tarantool VS Code extension automatically setups annotations on
system level by providing the default configuration within
`$HOME/.emmyrc.json`. This requires [VSCode Emmylua 0.9.18]
(https://github.com/EmmyLua/VSCode-EmmyLua/tree/0.9.18).

Closes #12

Author: georgiy-belyanin

CHANGELOG.md

@@ -8,6 +8,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+
+- Now the extension automatically setups Tarantool annotations without need to
+  explicitly execute any commands like `initialize VS Code extension`.
+
 ## [0.1.3] - 14.04.2025
 
 ### Added

package-lock.json

@@ -24,7 +24,9 @@
     "linter",
     "snippets"
   ],
-  "activationEvents": [],
+  "activationEvents": [
+    "onLanguage:lua"
+  ],
   "main": "./dist/extension.js",
   "contributes": {
     "commands": [
@@ -89,6 +91,7 @@
   "devDependencies": {
     "@octokit/core": "^5",
     "@types/command-exists": "^1.2.3",
+    "@types/lodash": "^4.17.16",
     "@types/mocha": "^10.0.10",
     "@types/node": "20.x",
     "@types/vscode": "^1.88.0",
@@ -99,6 +102,7 @@
     "command-exists": "^1.2.9",
     "copy-webpack-plugin": "^13.0.0",
     "eslint": "^9.23.0",
+    "lodash": "^4.17.21",
     "ts-loader": "^9.5.2",
     "typescript": "^5.8.2",
     "webpack": "^5.98.0",

package.json

@@ -1,6 +1,8 @@
 import * as vscode from 'vscode';
 import * as tt from './tt';
 import * as fs from 'fs';
+import * as os from 'os';
+import * as _ from 'lodash';
 
 const annotationsPaths = [
 	__dirname + "/Library",
@@ -14,6 +16,31 @@ const emmyrc = {
 		"library": annotationsPaths
 	}
 };
+const emmyrcFile = '.emmyrc.json';
+
+async function initGlobalEmmyrc() {
+	const globalEmmyrcPath = `${os.homedir()}/${emmyrcFile}`;
+
+	if (!fs.existsSync(globalEmmyrcPath)) {
+		fs.writeFileSync(globalEmmyrcPath, JSON.stringify(emmyrc, undefined, 2));
+		vscode.window.showInformationMessage(`Initialized ${globalEmmyrcPath} with Tarantool-specific settings`);
+		return;
+	}
+
+	const f = fs.readFileSync(globalEmmyrcPath, 'utf8');
+	const existingEmmyrc = JSON.parse(f);
+	const upToDate = _.isMatch(existingEmmyrc, emmyrc);
+	if (upToDate) {
+		vscode.window.showInformationMessage(`${globalEmmyrcPath} is up to date`);
+		return;
+	}
+
+	// TODO: Don't miss user-defined libraries.
+	const mergedEmmyrc = _.merge(existingEmmyrc, emmyrc);
+
+	fs.writeFileSync(globalEmmyrcPath, JSON.stringify(mergedEmmyrc, undefined, 2));
+	vscode.window.showInformationMessage(`Updated existing ${globalEmmyrcPath} with actual Tarantool-specific configuration`);
+}
 
 async function initVs() {
 	const file = vscode.window.activeTextEditor?.document.uri.fsPath;
@@ -31,7 +58,6 @@ async function initVs() {
 		return;
 	}
 
-	const emmyrcFile = '.emmyrc.json';
 	const filePath = vscode.Uri.file(`${wsPath}/${emmyrcFile}`);
 	if (fs.existsSync(filePath.fsPath)) {
 		const yes = "Yes";
@@ -41,7 +67,7 @@ async function initVs() {
 	}
 	wsedit.createFile(filePath, {
 		overwrite: true,
-		contents: Buffer.from(JSON.stringify(emmyrc))
+		contents: Buffer.from(JSON.stringify(emmyrc, undefined, 2))
 	});
 	vscode.workspace.applyEdit(wsedit);
 	vscode.window.showInformationMessage(`Created a new file: ${filePath.toString()}`);
@@ -66,6 +92,8 @@ export function activate(context: vscode.ExtensionContext) {
 		return;
 	}
 
+	initGlobalEmmyrc();
+
 	const commands = [
 		{ name: 'init-vs', cb: initVs },
 		{ name: 'create', cb: tt.create },