git-cat-file/lib/loose.js

Pure JavaScript `git cat-file -p` for node.js

"use strict";
/**
 * https://github.com/kawanet/git-cat-file
 */
Object.defineProperty(exports, "__esModule", { value: true });
exports.Loose = void 0;
const fs_1 = require("fs");
const zlib_1 = require("zlib");
const cache_1 = require("./cache");
class Loose {
    constructor(root) {
        this.root = root;
        this.readdir = (0, cache_1.shortCache)((first) => fs_1.promises.readdir(`${this.root}/objects/${first}`));
        //
    }
    async findAll(object_id) {
        const first = object_id.slice(0, 2);
        const rest = object_id.slice(2);
        const { length } = rest;
        const files = await this.readdir(first).catch(_ => null);
        if (!files)
            return;
        return files.filter(name => name.slice(0, length) === rest).map(name => (first + name));
    }
    async getObject(oid) {
        const first = oid.slice(0, 2);
        const rest = oid.slice(2);
        const obj = new LooseObject(`${this.root}/objects/${first}/${rest}`);
        const type = await obj.getType();
        const data = await obj.getData();
        return { oid, type, data };
    }
}
exports.Loose = Loose;
function findZero(buf, offset) {
    offset |= 0;
    while (buf[offset++]) {
        // nop
    }
    return offset;
}
class LooseObject {
    constructor(path) {
        this.path = path;
        //
    }
    getRaw() {
        return this.buf || (this.buf = fs_1.promises.readFile(this.path).then(zlib_1.inflateSync));
    }
    getOffset() {
        return this.offset || (this.offset = this.getRaw().then(findZero));
    }
    getType() {
        return this.type || (this.type = this.parseType());
    }
    async parseType() {
        const raw = await this.getRaw();
        const offset = await this.getOffset();
        const head = raw.slice(0, offset - 2).toString();
        return head.split(/\s+/).shift();
    }
    async getData() {
        const raw = await this.getRaw();
        const offset = await this.getOffset();
        return raw.slice(offset);
    }
}