only show picker when there is more than one formatter

src/vs/editor/contrib/format/format.ts

@@ -105,12 +105,11 @@ export abstract class FormattingConflicts {
 	}
 
 	static async select<T extends (DocumentFormattingEditProvider | DocumentRangeFormattingEditProvider)>(formatter: T[], document: ITextModel, mode: FormattingMode): Promise<T | undefined> {
-		if (formatter.length === 0) {
-			return undefined;
-		}
-		const { value: selector } = FormattingConflicts._selectors.iterator().next();
-		if (selector) {
-			return await selector(formatter, document, mode);
+		if (formatter.length > 1) {
+			const { value: selector } = FormattingConflicts._selectors.iterator().next();
+			if (selector) {
+				return await selector(formatter, document, mode);
+			}
 		}
 		return formatter[0];
 	}