flow-typed/dist/lib/codeSign.js

A repository of high quality flow type definitions

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.getSignedCodeVersion = getSignedCodeVersion;
exports.signCode = signCode;
exports.signCodeStream = signCodeStream;
exports.verifySignedCode = verifySignedCode;

var _md = _interopRequireDefault(require("md5"));

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

const VERSION_COMMENT_RE = /\/\/ flow-typed version: (.*)$/;

function getSignedCodeVersion(signedCode) {
  const [_, versionComment] = signedCode.split('\n');
  const versionMatches = versionComment.trim().match(VERSION_COMMENT_RE);

  if (versionMatches == null) {
    return null;
  }

  return versionMatches[1];
}

function signCode(code, version) {
  const versionedCode = `// flow-typed version: ${version}\n\n${code}`;
  const hash = (0, _md.default)(versionedCode);
  return `// flow-typed signature: ${hash}\n${versionedCode}`;
}

function signCodeStream(version) {
  return code => signCode(code, version);
}

const HASH_COMMENT_RE = /\/\/ flow-typed signature: (.*)$/;

function verifySignedCode(signedCode) {
  const signedCodeLines = signedCode.split('\n');
  const [hashComment] = signedCodeLines;
  const hashMatches = hashComment.trim().match(HASH_COMMENT_RE);

  if (hashMatches == null) {
    return false;
  }

  const [_, hash] = hashMatches;
  const versionedCode = signedCodeLines.slice(1).join('\n');
  return (0, _md.default)(versionedCode) === hash;
}