Fixes microsoft/monaco-editor#2327

src/vs/editor/editor.api.ts

@@ -8,6 +8,7 @@ import { createMonacoBaseAPI } from 'vs/editor/common/standalone/standaloneBase'
 import { createMonacoEditorAPI } from 'vs/editor/standalone/browser/standaloneEditor';
 import { createMonacoLanguagesAPI } from 'vs/editor/standalone/browser/standaloneLanguages';
 import { globals } from 'vs/base/common/platform';
+import { FormattingConflicts } from 'vs/editor/contrib/format/format';
 
 // Set defaults for standalone editor
 EditorOptions.wrappingIndent.defaultValue = WrappingIndent.None;
@@ -15,6 +16,10 @@ EditorOptions.glyphMargin.defaultValue = false;
 EditorOptions.autoIndent.defaultValue = EditorAutoIndentStrategy.Advanced;
 EditorOptions.overviewRulerLanes.defaultValue = 2;
 
+// We need to register a formatter selector which simply picks the first available formatter.
+// See https://github.com/microsoft/monaco-editor/issues/2327
+FormattingConflicts.setFormatterSelector((formatter, document, mode) => Promise.resolve(formatter[0]));
+
 const api = createMonacoBaseAPI();
 api.editor = createMonacoEditorAPI();
 api.languages = createMonacoLanguagesAPI();