src/vs/workbench/services/editor/browser/editorService.ts/EditorService/getAllNonDirtyEditors
class EditorService:	private getAllNonDirtyEditors(options: { includeUntitled: boolean, supportSideBySide: boolean }): IEditorInput[] {
		const editors: IEditorInput[] = [];

		function conditionallyAddEditor(editor: IEditorInput): void {
			if (editor.hasCapability(EditorInputCapabilities.Untitled) && !options.includeUntitled) {
				return;
			}

			if (editor.isDirty()) {
				return;
			}

			editors.push(editor);
		}

		for (const editor of this.editors) {
			if (options.supportSideBySide && editor instanceof SideBySideEditorInput) {
				conditionallyAddEditor(editor.primary);
				conditionallyAddEditor(editor.secondary);
			} else {
				conditionallyAddEditor(editor);
			}
		}

		return editors;
	}