Unexpected token when parsing a member expression after a property initializer in an object pattern

Bug Report

• I would like to work on a fix!

Current Behavior A clear and concise description of the behavior.

The following snippet will throw SyntaxError: Unexpected token, expected “,” Input Code

• REPL or Repo link if applicable: REPL

({ a = 42, b: {}.d } = {})

Expected behavior/code It should parse successfully.

Babel Configuration (babel.config.js, .babelrc, package.json#babel, cli command, .eslintrc): No plugin.

Environment REPL

Possible Solution We may reset refExpressionErrors.shortAssign when parsing Assignment Expression after eating tt.colon in parseObjectProperty.

https://github.com/babel/babel/blob/bfb82e778fea5b766e18066a68f79ae3fbbab9bc/packages/babel-parser/src/parser/expression.js#L1732

[nicolo-ribaudo]

It’s because chrome parses it as an expression. If you use @babel/parser’s parseExpression it will work, or you have to wrap it in parentheses: ({ a = 3 } = {}).

[vedantroy]

I would like to take this up. I’ve made a fork and I’m working on fixing the issue. What are next steps?