babel-preset-minify

• Install
• Usage
• Options

Install

npm install babel-preset-minify --save-dev

Usage

Via .babelrc (Recommended)

.babelrc

{
  "presets": ["minify"]
}

or pass in options -

{
  "presets": [["minify", {
    "mangle": {
      "exclude": ["MyCustomError"]
    },
    "unsafe": {
      "typeConstructors": false
    },
    "keepFnName": true
  }]]
}

Via CLI

babel script.js --presets minify

Via Node API

require("@babel/core").transform("code", {
  presets: ["minify"]
});

Options

Two types of options:

• 1-1 mapping with plugin
• The same option passed to multiple plugins

1-1 mapping with plugin

• false - disable plugin
• true - enable plugin
• { …pluginOpts } - enable plugin and pass pluginOpts to plugin

  OptionName	Plugin	DefaultValue
  booleans	transform-minify-booleans	true
  builtIns	minify-builtins	true
  consecutiveAdds	transform-inline-consecutive-adds	true
  deadcode	minify-dead-code-elimination	true
  evaluate	minify-constant-folding	true
  flipComparisons	minify-flip-comparisons	true
  guards	minify-guarded-expressions	true
  infinity	minify-infinity	true
  mangle	minify-mangle-names	true
  memberExpressions	transform-member-expression-literals	true
  mergeVars	transform-merge-sibling-variables	true
  numericLiterals	minify-numeric-literals	true
  propertyLiterals	transform-property-literals	true
  regexpConstructors	transform-regexp-constructors	true
  removeConsole	transform-remove-console	false
  removeDebugger	transform-remove-debugger	false
  removeUndefined	transform-remove-undefined	true
  replace	minify-replace	true
  simplify	minify-simplify	true
  simplifyComparisons	transform-simplify-comparison-operators	true
  typeConstructors	minify-type-constructors	true
  undefinedToVoid	transform-undefined-to-void	true

The same option passed to multiple plugins

• When multiple plugins require the same option, it's easier to declare it in one place. These options are passed on to two or more plugins.

  OptionName	Plugins
  keepFnName	Passed to mangle & deadcode
  keepClassName	Passed to mangle & deadcode
  tdz	Passed to builtIns, evaluate, deadcode, removeUndefined

Examples

{
  "presets": [["minify", {
    "evaluate": false,
    "mangle": true
  }]]
}

{
  "presets": [["minify", {
    "mangle": {
      "exclude": ["ParserError", "NetworkError"]
    }
  }]]
}

{
  "presets": [["minify", {
    "keepFnName": true
  }]]
}
// is the same as
{
  "presets": [["minify", {
    "mangle": {
      "keepFnName": true
    },
    "deadcode": {
      "keepFnName": true
    }
  }]]
}

You can read more about configuring preset options here