eve/dist/src/shared/guards.d.ts

Filesystem-first framework for durable backend AI agents that run anywhere.

/**
 * Small, unavoidable type guards used across the framework.
 *
 * Before adding a new guard: check whether `shared/json.ts`,
 * `shared/optional.ts`, or an existing standard-library predicate
 * already covers the case. This module exists specifically to stop
 * the same 3-line `typeof x === "object" && x !== null` pattern from
 * proliferating in every file that duck-types a field off an
 * `unknown` value.
 */
/**
 * Returns `true` when `value` is a non-null object that is not an
 * `Array`. Refines the type to `Record<string, unknown>` so callers
 * can duck-type fields without a subsequent `as { foo?: unknown }`
 * cast.
 *
 * Arrays are excluded because every use site in the codebase is
 * reading named fields (`value.message`, `value.errorId`,
 * `value.kind`, etc.) — none of which are meaningful on an array. If
 * you need "any non-null object including arrays", use
 * `typeof value === "object" && value !== null` inline.
 */
export declare function isObject(value: unknown): value is Record<string, unknown>;
/**
 * Returns `true` when `value` is a string with at least one
 * character. The zero-length check matters: empty strings routinely
 * fall out of optional-field projections (Slack `team_id`, HTTP
 * headers, JSON parse results) and should not be treated as a
 * meaningful value by display or correlation logic.
 */
export declare function isNonEmptyString(value: unknown): value is string;
/**
 * Returns `true` when `value` is a thenable — an object with a `then`
 * function. Used to reject async instrumentation metadata projectors
 * that accidentally return a Promise instead of a plain record.
 */
export declare function isThenable(value: unknown): value is PromiseLike<unknown>;
/**
 * Returns `true` when `error` is an `Error` carrying the given Node.js
 * `errno` code (`"ENOENT"`, `"EEXIST"`, ...). Filesystem control flow
 * routinely branches on these codes; this guard keeps the
 * `"code" in error` duck-typing in one place.
 */
export declare function isErrnoCode(error: unknown, code: string): boolean;
/**
 * Returns `true` when `value` is a plain object record — `{}`,
 * `Object.create(null)`, or an object whose prototype is
 * `Object.prototype`. Class instances, `Map`, `Date`, and other
 * exotic objects are excluded even though `isObject` would accept
 * them.
 */
export declare function isPlainRecord(value: unknown): value is Record<string, unknown>;