(fix) Format: Fall back to VSCode editor config (#553)

For tab size and whether or not to use spaces
#539

Author: dummdidumm

packages/language-server/src/plugins/svelte/SveltePlugin.ts

@@ -35,7 +35,11 @@ export class SveltePlugin
         CodeActionsProvider {
     private docManager = new Map<Document, SvelteDocument>();
 
-    constructor(private configManager: LSConfigManager, private prettierConfig: any) {}
+    constructor(
+        private configManager: LSConfigManager,
+        private prettierConfig: any,
+        private editorConfig?: any,
+    ) {}
 
     async getDiagnostics(document: Document): Promise<Diagnostic[]> {
         if (!this.featureEnabled('diagnostics')) {
@@ -67,7 +71,13 @@ export class SveltePlugin
         const prettier = importPrettier(filePath);
         // Try resolving the config through prettier and fall back to possible editor config
         const config =
-            (await prettier.resolveConfig(filePath, { editorconfig: true })) || this.prettierConfig;
+            (await prettier.resolveConfig(filePath, { editorconfig: true })) ||
+            this.prettierConfig ||
+            // Be defensive here because IDEs other than VSCode might not have these settings
+            (this.editorConfig && this.editorConfig.tabSize && {
+                tabWidth: this.editorConfig.tabSize,
+                useTabs: !this.editorConfig.insertSpaces,
+            });
         // Take .prettierignore into account
         const fileInfo = await prettier.getFileInfo(filePath, {
             ignorePath: this.prettierConfig?.ignorePath ?? '.prettierignore',

packages/language-server/src/server.ts

@@ -99,6 +99,7 @@ export function startServer(options?: LSOptions) {
             (sveltePlugin = new SveltePlugin(
                 configManager,
                 evt.initializationOptions?.prettierConfig || {},
+                evt.initializationOptions?.editorConfig, // deliberatly don't fall back to empty object
             )),
         );
         pluginHost.register(new HTMLPlugin(docManager, configManager));

packages/svelte-vscode/src/extension.ts

@@ -94,6 +94,7 @@ export function activate(context: ExtensionContext) {
         initializationOptions: {
             config: workspace.getConfiguration('svelte.plugin'),
             prettierConfig: workspace.getConfiguration('prettier'),
+            editorConfig: workspace.getConfiguration('editor', { languageId: 'svelte' }),
             dontFilterIncompleteCompletions: true, // VSCode filters client side and is smarter at it than us
         },
     };