fix(vscode-lsp): get latest config settings

When the LSP server asks the VS Code extension for configuration, the
extension responds with stale config. This is fine in the current use
case (where config is only fetched on initialization), but will become
confusing when we handle config updates.

Make the extension reply with the latest configs.

Author: strager

plugin/vscode-lsp/extension.js

@@ -14,7 +14,6 @@ let toDispose = [];
 async function startOrRestartServerAsync() {
   await stopServerIfStartedAsync();
 
-  let config = vscode.workspace.getConfiguration(clientID);
   client = new LanguageClient(
     clientID,
     "quick-lint-js-lsp",
@@ -31,7 +30,10 @@ async function startOrRestartServerAsync() {
       middleware: {
         workspace: {
           async configuration(params, _token, _next) {
-            return params.items.map((item) => getLSPWorkspaceConfig(item));
+            let vscodeConfig = getLatestWorkspaceConfig();
+            return params.items.map((item) =>
+              getLSPWorkspaceConfig(vscodeConfig, item)
+            );
           },
         },
       },
@@ -40,15 +42,16 @@ async function startOrRestartServerAsync() {
   client.start();
 
   function getQuickLintJSExecutablePath() {
+    let config = getLatestWorkspaceConfig();
     let path = config["executablePath"];
     let pathIsEmpty = /^\s*$/.test(path);
     return pathIsEmpty ? "quick-lint-js" : path;
   }
 
-  function getLSPWorkspaceConfig(lspConfigItem) {
+  function getLSPWorkspaceConfig(vscodeConfig, lspConfigItem) {
     switch (lspConfigItem.section) {
       case "quick-lint-js.tracing-directory":
-        return config.get("tracing-directory");
+        return vscodeConfig.get("tracing-directory");
 
       default:
         return null;
@@ -94,6 +97,10 @@ async function deactivateAsync() {
 }
 exports.deactivate = deactivateAsync;
 
+function getLatestWorkspaceConfig() {
+  return vscode.workspace.getConfiguration(clientID);
+}
+
 function logAsyncErrors(promise) {
   if (typeof promise === "function") {
     promise = promise();