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Migration from preset-env and plugin-transform-runtime

All the existig capabilities of @babel/preset-env and @babel/plugin-transform-runtime related to core-js are supported by the polyfill providers implemented in this repository.

core-js@3

Old configuration New configuration 
{
  "presets": [
    ["@babel/preset-env", {
      "targets": { "firefox": 42 },
      "useBuiltIns": "usage",
      "corejs": 3
    }]
  ]
}
 
{
  "targets": { "firefox": 42 },
  "presets": ["@babel/preset-env"],
  "plugins": [
    ["polyfill-corejs3", {
      "method": "usage-global"
    }]
  ]
}
Old configuration New configuration 
{
  "presets": [
    ["@babel/preset-env", {
      "targets": { "firefox": 42 },
      "useBuiltIns": "entry",
      "corejs": 3
    }]
  ]
}
 
{
  "targets": { "firefox": 42 },
  "presets": ["@babel/preset-env"],
  "plugins": [
    ["polyfill-corejs3", {
      "method": "entry-global"
    }]
  ]
}
Old configuration New configuration 
{
  "presets": [
    ["@babel/preset-env", {
      "targets": { "firefox": 42 }
    }]
  ],
  "plugins": [
    ["@babel/transform-runtime", {
      "corejs": 3
    }]
  ]
}
 
{
  "presets": [
    ["@babel/preset-env", {
      "targets": { "firefox": 42 }
    }]
  ],
  "plugins": [
    "@babel/transform-runtime",
    ["polyfill-corejs3", {
      "method": "usage-pure"
    }]
  ]
}

NOTE: The "Old" config doesn't support targets for polyfills, but you'll likely want to enable them by moving the targets option to the top-level.

es-shims

Old configuration (with core-js) New configuration 
{
  "presets": [
    ["@babel/preset-env", {
      "targets": { "firefox": 42 },
      "useBuiltIns": "usage",
      "corejs": 3
    }]
  ]
}
 
{
  "targets": { "firefox": 42 },
  "presets": ["@babel/preset-env"],
  "plugins": [
    ["polyfill-es-shims", {
      "method": "usage-global"
    }]
  ]
}
Old configuration (with core-js) New configuration 
{
  "presets": [
    ["@babel/preset-env", {
      "targets": { "firefox": 42 }
    }]
  ],
  "plugins": [
    ["@babel/transform-runtime", {
      "corejs": 3
    }]
  ]
}
 
{
  "presets": [
    ["@babel/preset-env", {
      "targets": { "firefox": 42 }
    }]
  ],
  "plugins": [
    "@babel/transform-runtime",
    ["polyfill-es-shims", {
      "method": "usage-pure",
    }]
  ]
}

NOTE: The "Old" config doesn't support targets for polyfills, but you'll likely want to enable them by moving the targets option to the top-level.

core-js@2

Old configuration New configuration 
{
  "presets": [
    ["@babel/preset-env", {
      "targets": { "firefox": 42 },
      "useBuiltIns": "usage",
      "corejs": 2
    }]
  ]
}
 
{
  "targets": { "firefox": 42 },
  "presets": ["@babel/preset-env"],
  "plugins": [
    ["polyfill-corejs2", {
      "method": "usage-global"
    }]
  ]
}
Old configuration New configuration 
{
  "presets": [
    ["@babel/preset-env", {
      "targets": { "firefox": 42 },
      "useBuiltIns": "entry",
      "corejs": 2
    }]
  ]
}
 
{
  "targets": { "firefox": 42 },
  "presets": ["@babel/preset-env"],
  "plugins": [
    ["polyfill-corejs2", {
      "method": "entry-global"
    }]
  ]
}
Old configuration New configuration 
{
  "presets": [
    ["@babel/preset-env", {
      "targets": { "firefox": 42 }
    }]
  ],
  "plugins": [
    ["@babel/transform-runtime", {
      "corejs": 2
    }]
  ]
}
 
{
  "presets": [
    ["@babel/preset-env", {
      "targets": { "firefox": 42 }
    }]
  ],
  "plugins": [
    "@babel/transform-runtime",
    ["polyfill-corejs2", {
      "method": "usage-pure"
    }]
  ]
}

NOTE: The "Old" config doesn't support targets for polyfills, but you'll likely want to enable them by moving the targets option to the top-level.