panic: Expected scope (7, 0) in index.ts, found scope (7, 2) (while parsing "index.ts")

[jakebailey]

I was futzing around with decorators and thought I'd throw a new-style decorator into esbuild to see what old-style decorators would have output (was too lazy to open a new TS playground and change settings).

I was surprised to see a panic:

Error: Build failed with 1 error:
error: panic: Expected scope (7, 0) in index.ts, found scope (7, 2) (while parsing "index.ts")

The code is just:

@((target, context) => {
  target.staticProp
  //      ^?
})
class Foo {
  static staticProp = 1234;
}

Which, is not legal TS code for old-style decorators, but is for new-style. esbuild doesn't support new style decorators yet, but, the panicking seems unintentional.

esbuild playground

[hyrious]

Except for the new decorator proposal, the decorator expression is also valid TypeScript.

TypeScript Playground Link

[jakebailey]

Hm. With my exact code, I got errors. Maybe that's not right.

[jakebailey]

Ah, it's just because of that second parameter, apparently.

[evanw]

Sorry about that. Looks like I'm missing test coverage for decorators that are inline function expressions. Will fix.

[jakebailey]

Thanks for the fix!