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 73133x 133x 133x 133x 133x 133x 133x 133x 133x 133x 133x 3x 133x 133x 4x 4x 4x 4x 4x 133x 6x 6x 6x 6x 6x 6x 6x 6x 6x 133x 133x 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 133x 133x 133x  
'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;