/** A readable failure walking ancestors or diffing trees. Callers treat any
 *  throw from this module as "fall back to a full capture", never as fatal. */
export declare class AncestorBaselineError extends Error {
}
/** How many first-parent ancestors of the requested commit the walk considers. */
export declare const DEFAULT_ANCESTOR_WALK_LIMIT = 50;
/** First-parent ancestors of `sha`, nearest first, excluding `sha` itself,
 *  bounded to `limit`. A shallow history simply yields fewer ancestors; a git
 *  failure (unknown SHA, not a repository) throws {@link AncestorBaselineError}. */
export declare function listFirstParentAncestors(options: {
    sha: string;
    cwd: string;
    limit?: number;
}): string[];
/** Paths changed between two commits' TREES (`git diff --name-only A B`). */
export declare function changedPathsBetween(options: {
    ancestorSha: string;
    sha: string;
    cwd: string;
}): string[];
/**
 * The subset of `changedPaths` that is capture-relevant, conservatively:
 * the capture spec and anything in its directory (colocated harness files),
 * the Playwright capture config, any `styleproof.config.json`, any package
 * manifest/lockfile, and anything under a declared app source root. With NO
 * source roots declared — or a root that canonicalizes to the repo root — every
 * changed path is relevant, so reuse can never fire on an undeclared app
 * layout. Pure and fs-free.
 */
export declare function captureRelevantChangedPaths(options: {
    changedPaths: readonly string[];
    spec: string;
    sourceRoots: readonly string[];
}): string[];
/** The verdict of {@link planAncestorBaselineReuse}: reuse names the ancestor
 *  and carries the no-relevant-changes proof; capture names the reason. */
export type AncestorBaselineReusePlan = {
    decision: 'reuse';
    ancestorSha: string;
    ancestorDepth: number;
    changedPathCount: number;
} | {
    decision: 'capture';
    reason: string;
};
/**
 * Decide whether the nearest stored-ancestor bundle may serve as the requested
 * commit's baseline. FAIL-SAFE BY CONTRACT: any error in the walk or the diff
 * returns a `capture` verdict with the failure as its reason — this function
 * never throws and never returns a reuse verdict it could not prove.
 */
export declare function planAncestorBaselineReuse(options: {
    requestedSha: string;
    /** Commit SHAs that have a stored bundle (top-level dirs of the map store branch). */
    availableShas: ReadonlySet<string>;
    spec: string;
    sourceRoots: readonly string[];
    cwd: string;
    limit?: number;
}): AncestorBaselineReusePlan;