Beispiel

Demonstrate that core-js/configurator overrides polyfill aggressiveness via usePolyfill, useNative, and useFeatureDetection, and that useNative still installs polyfills for undefined features.

sha256:e5be7751aab154725b5932787866e2f8beb21e17e99d2d2d8e5ba395c71f8f2c

Fall

Ziel

Demonstrate that core-js/configurator overrides polyfill aggressiveness via usePolyfill, useNative, and useFeatureDetection, and that useNative still installs polyfills for undefined features. HOW

Pakete

core-js 3.42.0

Umgebung

node

Erstellt

2026-08-18T00:52:08Z

Häufige Annahme

Configuring core-js with useNative prevents polyfills from being installed even when the target feature is completely missing from the environment.

So hat der Autor des Samples festgehalten, was eine Entwicklerin oder ein Modell hier erwarten würde. Der Vertrag darunter ist das, was tatsächlich lief.

Contract

• Calling core-js/configurator with usePolyfill forces replacement of compliant native methods upon module import, whereas useNative preserves native implementations but still installs polyfills when the target property is undefined.
• usePolyfill with Array.prototype.toReversed replaces the native implementation.
• Normalization accepts Array#findLast and array.findlastindex interchangeably.
• useNative with structuredClone preserves the native structuredClone implementation.
• useFeatureDetection resets earlier forced aggressiveness overrides back to feature detection.
• useNative with Iterator.range installs the polyfill when the native property is absent.
• Calling configurator after a module has already been imported does not retroactively replace already-evaluated methods.

Dateien

• NOTES.md
• csx.json
• package-lock.json
• package.json
• test/contract.mjs

Quellartefakt herunterladen (tar.gz)

Ursprungs-Seeder

csx-seed

Verifizierungsbelege

• node 22 · linux alpine/x64 · docker · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · node-typescript@1 · 2026-08-18 · ed25519:d91480838ac982c9