/** Root-level candidates, in precedence order within one directory. */
export declare const CONFIG_BASENAMES: string[];
/** The directory holding lookout's working state, and the config's old home. */
export declare const LOOKOUT_DIR = ".lookout";
/** Pre-root candidates, still loadable and migrated on sight. */
export declare const LEGACY_BASENAMES: string[];
/** The canonical file lookout writes and maintains. */
export declare const CONFIG_FILENAME: string;
export interface LocatedConfig {
    /** Absolute path of the config file. */
    path: string;
    /** The project root it implies: evidence and the backlog hang off this. */
    projectDir: string;
    /** True when it was found in the pre-root `.lookout/` home. */
    legacy: boolean;
}
/** The nearest config at or above `start`, or null when there is none. */
export declare function locateConfig(start: string): LocatedConfig | null;
/** True when a config path sits in the pre-root `.lookout/` home. */
export declare function isLegacyConfigPath(path: string): boolean;
/**
 * The project root a config path implies, for `--config` as much as for
 * discovery: a file inside `.lookout/` roots at that directory's parent, and a
 * file anywhere else roots where it sits.
 */
export declare function projectDirFor(path: string): string;
/**
 * Where a config lookout writes itself should go.
 *
 * A repository root or a package root is a place someone meant to keep files;
 * a directory that is neither is somewhere they happened to be standing, and
 * writing a config file into it would be litter. Returning null is how the
 * caller learns to stay zero-config.
 *
 * The home directory is never a project root, whatever it has in it. Plenty of
 * people keep their dotfiles in a git repository, and a run made from some
 * unrelated folder underneath it must not be answered by writing a config file
 * into their home.
 */
export declare function nearestProjectRoot(start: string): string | null;