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babel-core doesn't list which plugins/presets are duplicated

See original GitHub issue

Bug Report

Current Behavior babel-core doesn’t list which plugins/presets are duplicated:

   Duplicate plugin/preset detected.
    If you'd like to use two separate instances of a plugin,
    they need separate names, e.g.

      plugins: [
        ['some-plugin', {}],
        ['some-plugin', {}, 'some unique name'],
      ]

      at assertNoDuplicates (node_modules/@babel/core/lib/config/config-descriptors.js:205:13)
      at createDescriptors (node_modules/@babel/core/lib/config/config-descriptors.js:114:3)
      at createPluginDescriptors (node_modules/@babel/core/lib/config/config-descriptors.js:105:10)
      at alias (node_modules/@babel/core/lib/config/config-descriptors.js:63:49)
      at cachedFunction (node_modules/@babel/core/lib/config/caching.js:33:19)
      at plugins.plugins (node_modules/@babel/core/lib/config/config-descriptors.js:28:77)
      at mergeChainOpts (node_modules/@babel/core/lib/config/config-chain.js:319:26)
      at node_modules/@babel/core/lib/config/config-chain.js:283:7
      at buildRootChain (node_modules/@babel/core/lib/config/config-chain.js:68:29)
      at loadPrivatePartialConfig (node_modules/@babel/core/lib/config/partial.js:85:55)

Expected behavior/code A list of duplicate plugins/presets so that you know which ones to remove or rename.

Babel Configuration (.babelrc, package.json, cli command)

  "babel": {
    "plugins": [
      "@babel/plugin-proposal-class-properties",
      "@babel/plugin-syntax-dynamic-import",
      "@babel/plugin-transform-runtime",
      "babel-plugin-istanbul",
      "babel-plugin-styled-components",
      "syntax-export-extensions"
    ],
    "presets": [
      ["@babel/preset-env", {
        "debug": true
      }],
      ["@babel/preset-react", { "debug":  true }]
    ]
  },

Environment

Babel version(s): 7.4.0
Node/npm version: Node 10/npm 6
OS: macOS 10.14.3

Issue Analytics

State:
Created 4 years ago
Reactions:1
Comments:9 (3 by maintainers)

Top GitHub Comments

1reaction

nicolo-ribaudocommented, Jun 10, 2019

You should probably exclude the object rest-spread plugin from @babel/preset-env

0reactions

luminous3commented, Jun 10, 2019

That actually fixed the error, thanks @nicolo-ribaudo

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