@sema-agent/core/dist/core/file-history-retention.js

Stateless, task-oriented AI agent core

import { refuseRetentionPolicy } from "./retention-policy.js";
export const DEFAULT_FILE_HISTORY_BOUNDARY_KEEP = 100;
const KNOWN_KNOBS = new Set(["keep"]);
export function resolveFileHistoryRetention(label, policy) {
    if (policy === undefined)
        return DEFAULT_FILE_HISTORY_BOUNDARY_KEEP;
    if (typeof policy !== "object" || policy === null || Array.isArray(policy)) {
        refuseRetentionPolicy(label, "retention", policy, `an object of retention knobs (${[...KNOWN_KNOBS].join(", ")}) or omitted`);
    }
    const unknown = Object.keys(policy).filter((k) => !KNOWN_KNOBS.has(k));
    if (unknown.length > 0) {
        const first = unknown[0];
        refuseRetentionPolicy(label, `retention.${first}`, policy[first], `omitted — ${JSON.stringify(first)} is not a retention knob (the only knob is "keep"), and a misspelled one would leave the engine default in force while the operator believes their own number is`);
    }
    const keep = policy.keep;
    if (keep === undefined)
        return DEFAULT_FILE_HISTORY_BOUNDARY_KEEP;
    if (keep === "unbounded")
        return null;
    if (keep === 0) {
        refuseRetentionPolicy(label, "retention.keep", keep, `at least 1 boundary — a cap of 0 would reap the boundary its own commit just minted, leaving a rewind seat that answers ok to every snapshot and false to every canRestore; write "unbounded" to mean "do not trim" (omitting the knob does NOT mean that — it selects the engine default of ${DEFAULT_FILE_HISTORY_BOUNDARY_KEEP})`);
    }
    if (typeof keep !== "number" || !Number.isInteger(keep) || keep < 1) {
        refuseRetentionPolicy(label, "retention.keep", keep, `a whole number of boundaries, 1 or more, or the literal "unbounded"`);
    }
    return keep;
}
export function fileHistoryBoundariesToKeep(orderedOldestFirst, justCommitted, keep) {
    if (orderedOldestFirst.length <= keep)
        return null;
    const survivors = new Set([justCommitted]);
    for (let i = orderedOldestFirst.length - 1; i >= 0 && survivors.size < keep; i--) {
        survivors.add(orderedOldestFirst[i]);
    }
    return [...survivors];
}