SetAnonymousDefaultNameRuntimeModule.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 SetAnonymousDefaultNameRuntimeModule extends HelperRuntimeModule {
  10. constructor() {
  11. super("set anonymous default export name");
  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.setAnonymousDefaultName;
  30. return Template.asString([
  31. "// set .name for anonymous default exports per ES spec",
  32. "// skipped when the property is non-configurable (pre-ES2015 engines),",
  33. "// where Object.defineProperty would throw",
  34. `${fn} = ${runtimeTemplate.basicFunction("x", [
  35. 'var descriptor = Object.getOwnPropertyDescriptor(x, "name");',
  36. 'if (!descriptor || (!descriptor.writable && descriptor.configurable)) Object.defineProperty(x, "name", { value: "default", configurable: true });'
  37. ])};`
  38. ]);
  39. }
  40. }
  41. module.exports = SetAnonymousDefaultNameRuntimeModule;