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Error using react-native cli after upgrading to v0.40.0-rc.*

See original GitHub issue

Description

Upgraded from v0.39.0 to v0.40.0-rc.1 When executing run-android or upgrade, the following output is displayed.

...\node_modules\babel-core\lib\transformation\file\index.js:600
      throw err;
      ^

SyntaxError: .../node_modules/react-native/packager/react-packager/src/Bundler/index.js: Unexpected token, expected ) (42:8)
  40 |
  41 | export type GetTransformOptions<T> = (
> 42 |   string,
     |         ^
  43 |   Object,
  44 |   string => Promise<Array<string>>,
  45 | ) => T | Promise<T>;
    at Parser.pp$5.raise (...\node_modules\babylon\lib\index.js:4215:13)
    at Parser.pp.unexpected (...\node_modules\babylon\lib\index.js:1599:8)
    at Parser.pp.expect (...\node_modules\babylon\lib\index.js:1587:33)
    at Parser.pp$7.flowParsePrimaryType (...\node_modules\babylon\lib\index.js:4952:14)
    at Parser.pp$7.flowParsePostfixType (...\node_modules\babylon\lib\index.js:5025:38)
    at Parser.pp$7.flowParsePrefixType (...\node_modules\babylon\lib\index.js:5041:17)
    at Parser.pp$7.flowParseIntersectionType (...\node_modules\babylon\lib\index.js:5047:19)
    at Parser.pp$7.flowParseUnionType (...\node_modules\babylon\lib\index.js:5057:19)
    at Parser.pp$7.flowParseType (...\node_modules\babylon\lib\index.js:5068:19)
    at Parser.pp$7.flowParseTypeInitialiser (...\node_modules\babylon\lib\index.js:4393:19)

It is the first time I encountered this error. Downgrading back to 0.39.0 fixes this issue.