src/vs/workbench/services/label/common/labelService.ts/LabelService/getUriBasenameLabel
class LabelService:	getUriBasenameLabel(resource: URI): string {
		const formatting = this.findFormatting(resource);
		const label = this.doGetUriLabel(resource, formatting);

		let pathLib: typeof win32 | typeof posix;
		if (formatting?.separator === win32.sep) {
			pathLib = win32;
		} else if (formatting?.separator === posix.sep) {
			pathLib = posix;
		} else {
			pathLib = (this.os === OperatingSystem.Windows) ? win32 : posix;
		}

		return pathLib.basename(label);
	}