Interleaving buggy with JSX, expressions, and braces in expressions

[wooorm]

Initial checklist

• I read the support docs
• I read the contributing guide
• I agree to follow the code of conduct
• I searched issues and couldn’t find anything (or linked relevant results below)

Affected packages and versions

latest

Link to runnable example

mdx playground

Steps to reproduce

<a>{[
  'b',
  {name: 'c'}
]}</a>

Expected behavior

No crash, as changing {name: 'c'} to 'c' works. No reason for that.

Actual behavior

Crash

Runtime

No response

Package manager

No response

OS

No response

Build and bundle tools

No response

[wooorm]

Ah, this is complex. Did some digging and what’s going on is that “blocks” are parsed before “inlines”. When parsing blocks, roughly this happens:

<a>{[ <-- this is not a block because there’s a `{` after it.
  'b',  <-- just random text
  {name: 'c'} <-- found a block! let’s parse the expression; ok `name` is an identifier; wait there’s more? That isn’t a valid expression: throw!
]}</a>