Created VSCode Extension, some updates from LinkedLives in the field

VSCode/scripts/main.js

@@ -0,0 +1,69 @@
+import * as vscode from 'vscode';
+
+const typeScriptExtensionId = 'vscode.typescript-language-features';
+const pluginId = 'typescript-lit-html-plugin';
+const configurationSection = 'lit-html';
+
+export async function activate(context) {
+  const extension = vscode.extensions.getExtension(typeScriptExtensionId);
+
+  if (!extension) {
+    return;
+  }
+
+  await extension.activate();
+
+  if (!extension.exports || !extension.exports.getAPI) {
+    return;
+  }
+
+  const api = extension.exports.getAPI(0);
+
+  if (!api) {
+    return;
+  }
+
+  vscode.workspace.onDidChangeConfiguration(e => {
+    if (e.affectsConfiguration(configurationSection)) {
+      synchronizeConfiguration(api);
+    }
+  }, undefined, context.subscriptions);
+
+  synchronizeConfiguration(api);
+}
+
+function synchronizeConfiguration(api) {
+  api.configurePlugin(pluginId, getConfiguration());
+}
+
+function getConfiguration() {
+  const config = vscode.workspace.getConfiguration(configurationSection);
+  const outConfig = {
+    format: {}
+  };
+
+  withConfigValue(config, 'tags', tags => { outConfig.tags = tags; });
+  withConfigValue(config, 'format.enabled', enabled => { outConfig.format.enabled = enabled; });
+
+  return outConfig;
+}
+
+function withConfigValue(config, key, withValue) {
+  const configSetting = config.inspect(key);
+  
+  if (!configSetting) {
+    return;
+  }
+
+  // Make sure the user has actually set the value.
+  // VS Code will return the default values instead of `undefined`, even if user has not don't set anything.
+  if (typeof configSetting.globalValue === 'undefined' && typeof configSetting.workspaceFolderValue === 'undefined' && typeof configSetting.workspaceValue === 'undefined') {
+    return;
+  }
+
+  const value = config.get(key, undefined);
+
+  if (typeof value !== 'undefined') {
+    withValue(value);
+  }
+}