babel-preset-proposals

babel-preset-proposals

A Babel 7 preset to manage experimental proposal plugin dependencies and usage, providing default configuration for plugins which have mandatory options, and ensuring that proposal plugins which affect one another are used in the correct order and have appropriate options set.

Install

npm install babel-preset-proposals

Options

absolutePaths

boolean, defaults to false.

Use absolute paths in plugins config - use this option if you're creating a Babel configuration which will be used outside of the module resolution scope of where you're generating it.

all

boolean, defaults to false.

Enable all plugins which haven't been otherwise configured.

loose

boolean

Sets the loose option for all plugins which are enabled and have a loose option - primarily intended for flipping plugin loose options to true, since they default to false.

Plugin Options

boolean or an Object, defaults to false.

To enable a plugin, pass its option as true:

{
  "presets": [
    ["babel-preset-proposals", {
      "classProperties": true,
      "decorators": true,
      "exportDefaultFrom": true,
      "exportNamespaceFrom": true
    }]
  ]
}

If the plugin takes options, you can pass an options Object for it.

{
  "presets": [
    ["babel-preset-proposals", {
      "decorators": {"legacy": true}
    }]
  ]
}

Preset option	Babel Plugin Docs
functionBind	@babel/plugin-proposal-function-bind
exportDefaultFrom	@babel/plugin-proposal-export-default-from
logicalAssignmentOperators	@babel/plugin-proposal-logical-assignment-operators
pipelineOperator	@babel/plugin-proposal-pipeline-operator
doExpressions	@babel/plugin-proposal-do-expressions
decorators	@babel/plugin-proposal-decorators
functionSent	@babel/plugin-proposal-function-sent
exportNamespaceFrom	@babel/plugin-proposal-export-namespace-from
numericSeparator	@babel/plugin-proposal-numeric-separator
throwExpressions	@babel/plugin-proposal-throw-expressions
dynamicImport	@babel/plugin-syntax-dynamic-import
importMeta	@babel/plugin-syntax-import-meta
classStaticBlock	@babel/plugin-proposal-class-static-block
classProperties	@babel/plugin-proposal-class-properties

If a plugin requires configuration and you enable it with a true option, this preset will provide default options:

Preset option	Default plugin options
decorators	{decoratorsBeforeExport: false} (as per this decision in the proposal repo)
pipelineOperator	{proposal: 'minimal'}

API

validateOptions(options?: Object): String[]

The validation this plugin performs on its options is exported if you need to use it in tooling which accepts user configuration, as you may want to report option validation issues yourself rather than letting Babel blow up.

It returns an Array of error messages, which will be empty if options were valid.

Versioning

Proposal plugins will never be stable, so this package will always be at a 0.X version and will make breaking changes as necessary, so lock it to the specific 0.X version you're using.

MIT Licensed