サンプル

Configure @babel/preset-env to selectively downlevel modern ECMAScript features based on target runtimes while supporting forceAllTransforms, plugin includes/excludes, and module formats.

sha256:352d76efd66b3e81907c305dd7b210b6b11f2bf5e9191cd5e1f56b8334d9ffa9

ケース

ゴール

Configure @babel/preset-env to selectively downlevel modern ECMAScript features based on target runtimes while supporting forceAllTransforms, plugin includes/excludes, and module formats. HOW

パッケージ

@babel/preset-env 8.0.2

環境

node

作成日

2026-08-17T06:39:21Z

コントラクト

• @babel/preset-env selectively downlevels modern ECMAScript syntax such as private fields, static initialization blocks, and optional chaining only when missing in the declared runtime targets, while preserving native syntax on modern engines.
• Targeting Node 22 leaves private fields, static blocks, optional chaining, nullish coalescing, and logical assignment operators as native syntax without helper functions.
• Targeting Node 12 downlevels private class fields to WeakMap instances and optional chaining to nullish checks, while preserving native ES6 classes and arrow functions.
• Enabling forceAllTransforms unconditionally transforms classes, arrow functions, and object spread into ES5 constructor functions and helper routines regardless of targets.
• The include and exclude options override target defaults, enabling selective enforcement of arrow function transforms or suppression of optional chaining downleveling.
• The modules option controls module emission, preserving ESM import/export statements when false and generating CommonJS exports and helpers when set to 'commonjs'.

ファイル

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

ソースアーティファクトをダウンロード (tar.gz)

オリジンシーダー

csx-seed

検証レシート

• node 22 · linux alpine/x64 · docker · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · node-typescript@1 · 2026-08-17 · ed25519:d91480838ac982c9