All files / lib/internal/modules/esm create_dynamic_module.js

95.83% Statements 69/72
88.88% Branches 8/9
71.42% Functions 5/7
95.83% Lines 69/72

Press n or j to go to the next uncovered block, b, p or k for the previous block.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73142x 142x 142x 142x 142x 142x 142x 142x 142x 142x 142x 3x 142x 142x 4x 4x 4x 4x 4x 142x 6x 6x 6x 6x 6x 6x 6x 6x 6x 142x 142x 4x 4x 4x 4x 4x 4x 4x 4x 4x 4x 4x 4x 4x 4x 4x 4x 4x 4x 4x 4x 2x 2x 2x 2x 2x 2x 2x       2x 4x 4x 4x 4x 4x 4x 4x 142x 142x 142x  
'use strict';
 
const {
  ArrayPrototypeJoin,
  ArrayPrototypeMap,
  JSONStringify,
  ObjectCreate,
  SafeSet,
} = primordials;
 
let debug = require('internal/util/debuglog').debuglog('esm', (fn) => {
  debug = fn;
});
 
function createImport(impt, index) {
  const imptPath = JSONStringify(impt);
  return `import * as $import_${index} from ${imptPath};
import.meta.imports[${imptPath}] = $import_${index};`;
}
 
function createExport(expt) {
  const name = `${expt}`;
  return `let $${name};
export { $${name} as ${name} };
import.meta.exports.${name} = {
  get: () => $${name},
  set: (v) => $${name} = v,
};`;
}
 
const createDynamicModule = (imports, exports, url = '', evaluate) => {
  debug('creating ESM facade for %s with exports: %j', url, exports);
  const source = `
${ArrayPrototypeJoin(ArrayPrototypeMap(imports, createImport), '\n')}
${ArrayPrototypeJoin(ArrayPrototypeMap(exports, createExport), '\n')}
import.meta.done();
`;
  const { ModuleWrap, callbackMap } = internalBinding('module_wrap');
  const m = new ModuleWrap(`${url}`, undefined, source, 0, 0);
 
  const readyfns = new SafeSet();
  const reflect = {
    exports: ObjectCreate(null),
    onReady: (cb) => { readyfns.add(cb); },
  };
 
  if (imports.length)
    reflect.imports = ObjectCreate(null);
 
  callbackMap.set(m, {
    initializeImportMeta: (meta, wrap) => {
      meta.exports = reflect.exports;
      if (reflect.imports)
        meta.imports = reflect.imports;
      meta.done = () => {
        evaluate(reflect);
        reflect.onReady = (cb) => cb(reflect);
        for (const fn of readyfns) {
          readyfns.delete(fn);
          fn(reflect);
        }
      };
    },
  });
 
  return {
    module: m,
    reflect,
  };
};
 
module.exports = createDynamicModule;