CompatGetDefaultExportRuntimeModule.js 1.6 KB

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  1. /*
  2. MIT License http://www.opensource.org/licenses/mit-license.php
  3. */
  4. "use strict";
  5. const RuntimeGlobals = require("../RuntimeGlobals");
  6. const Template = require("../Template");
  7. const HelperRuntimeModule = require("./HelperRuntimeModule");
  8. /** @import Compilation from "../Compilation" */
  9. class CompatGetDefaultExportRuntimeModule extends HelperRuntimeModule {
  10. constructor() {
  11. super("compat get default export");
  12. }
  13. /**
  14. * Returns true, if the runtime module should get it's own scope.
  15. * When false, `generate()` must emit complete statements ending with `;`
  16. * so a following runtime IIFE is not parsed as a call (ASI).
  17. * @returns {boolean} true, if the runtime module should get it's own scope
  18. */
  19. shouldIsolate() {
  20. return false;
  21. }
  22. /**
  23. * Generates runtime code for this runtime module.
  24. * @returns {string | null} runtime code
  25. */
  26. generate() {
  27. const compilation = /** @type {Compilation} */ (this.compilation);
  28. const { runtimeTemplate } = compilation;
  29. const fn = RuntimeGlobals.compatGetDefaultExport;
  30. return Template.asString([
  31. "// getDefaultExport function for compatibility with non-harmony modules",
  32. `${fn} = ${runtimeTemplate.basicFunction("module", [
  33. `${runtimeTemplate.renderConst()} getter = module && module.__esModule ?`,
  34. Template.indent([
  35. `${runtimeTemplate.returningFunction("module['default']")} :`,
  36. `${runtimeTemplate.returningFunction("module")};`
  37. ]),
  38. `${RuntimeGlobals.definePropertyGetters}(getter, { a: getter });`,
  39. "return getter;"
  40. ])};`
  41. ]);
  42. }
  43. }
  44. module.exports = CompatGetDefaultExportRuntimeModule;