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babel-plugin-redux-saga cannot read property start of undefined

See original GitHub issue

Description of the bug/issue

Hi,

I just updated to version 1.0.0 from 1.0.0-rc-0. Everything is working good until I added the babel-plugin then I’m getting exception: TypeError: Cannot read property 'start' of undefined

here is the stactrace:

TypeError: Cannot read property 'start' of undefined
    at calcLocation (/Users/project/node_modules/babel-plugin-redux-saga/src/index.js:57:26)
    at PluginPass.FunctionExpression (/Users/project/node_modules/babel-plugin-redux-saga/src/index.js:116:26)
    at newFn (/Users/project/node_modules/@babel/core/node_modules/@babel/traverse/lib/visitors.js:193:21)
    at NodePath._call (/Users/project/node_modules/@babel/core/node_modules/@babel/traverse/lib/path/context.js:53:20)
    at NodePath.call (/Users/project/node_modules/@babel/core/node_modules/@babel/traverse/lib/path/context.js:40:17)
    at NodePath.visit (/Users/project/node_modules/@babel/core/node_modules/@babel/traverse/lib/path/context.js:88:12)
    at TraversalContext.visitQueue (/Users/project/node_modules/@babel/core/node_modules/@babel/traverse/lib/context.js:118:16)
    at TraversalContext.visitMultiple (/Users/project/node_modules/@babel/core/node_modules/@babel/traverse/lib/context.js:85:17)
    at TraversalContext.visit (/Users/project/node_modules/@babel/core/node_modules/@babel/traverse/lib/context.js:144:19)
    at Function.traverse.node (/Users/project/node_modules/@babel/core/node_modules/@babel/traverse/lib/index.js:94:17)
    at NodePath.visit (/Users/project/node_modules/@babel/core/node_modules/@babel/traverse/lib/path/context.js:95:18)
    at TraversalContext.visitQueue (/Users/project/node_modules/@babel/core/node_modules/@babel/traverse/lib/context.js:118:16)
    at TraversalContext.visitSingle (/Users/project/node_modules/@babel/core/node_modules/@babel/traverse/lib/context.js:90:19)
    at TraversalContext.visit (/Users/project/node_modules/@babel/core/node_modules/@babel/traverse/lib/context.js:146:19)
    at Function.traverse.node (/Users/project/node_modules/@babel/core/node_modules/@babel/traverse/lib/index.js:94:17)
    at NodePath.visit (/Users/project/node_modules/@babel/core/node_modules/@babel/traverse/lib/path/context.js:95:18)

Steps to reproduce the bug/issue

for me it was just to add the babel-plugin-redux-saga. removing it just works.

here is my babel file:

module.exports = {
  presets: [
    ['@babel/env', { modules: false }],
    '@babel/react',
  ],
  plugins: [
    'babel-plugin-redux-saga',
    '@babel/syntax-dynamic-import',
    '@babel/plugin-proposal-export-namespace-from',
    'babel-plugin-styled-components',
    'react-hot-loader/babel',
    '@babel/plugin-proposal-class-properties',
    ['transform-imports', {
      ramda: {
        transform: importName => `ramda/es/${importName}`,
        preventFullImport: true,
      },
    }],
  ],
  env: {
    test: {
      presets: [
        ['@babel/env'],
        '@babel/react',
      ],
      plugins: [
        'babel-plugin-styled-components',
      ],
    },
  },
};

Issue Analytics

State:
Created 5 years ago
Comments:6 (3 by maintainers)

Top GitHub Comments

2reactions

mshustovcommented, Jan 27, 2019

should fix https://github.com/redux-saga/redux-saga/pull/1745

1reaction

royipressburgercommented, Jan 27, 2019

@Andarist Hi again I found the issue, This happens when you have some class function with the async prefix.

To reproduce it just clone this repo. add the babel-plugin-redux-saga Then under app/containers/HomePage/HomePage.js add async to the componentDidMount function, and you will see the error