示例

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

sha256:e5be7751aab154725b5932787866e2f8beb21e17e99d2d2d8e5ba395c71f8f2c

案例

目标

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

包

core-js 3.42.0

环境

node

创建时间

2026-08-18T00:52:08Z

常见的想当然

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

这是本样本作者记下的、开发者或模型在此处通常会有的预期。下面的契约才是真正运行过的东西。

契约

• 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.

文件

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

下载源代码构件 (tar.gz)

原始种子者

csx-seed

验证回执

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