import type { ClickHouseClient } from "@clickhouse/client";
import type { MigrationLogger } from "./logger.js";
export declare function hasSqlContent(chunk: string): boolean;
/**
 * Extract a `-- fjall:skip-if: <SQL expression>` directive from a migration
 * file's leading comment block (consecutive lines from the top that are empty
 * or start with `--`). A directive appearing after the first statement is
 * deliberately NOT honoured — the contract is file-level, declared up front.
 *
 * Returns the expression, or `undefined` when no directive is present.
 * Throws on a duplicate directive or an empty expression (an unevaluable
 * guard must fail loudly, never silently authorise or omit a skip).
 */
export declare function parseSkipIfDirective(sql: string): string | undefined;
export interface RunSqlMigrationsOpts {
    client: ClickHouseClient;
    dir: string;
    skipFilesMatching?: RegExp;
    signal?: AbortSignal;
    logger?: MigrationLogger;
}
export interface RunSqlMigrationsResult {
    applied: readonly string[];
}
export declare function runSqlMigrations(opts: RunSqlMigrationsOpts): Promise<RunSqlMigrationsResult>;