OXC incorrectly removes parentheses around arrow function object literal in Angular output

[tomer953]

Bug: Arrow function returning object literal loses parentheses

OXC sometimes drops the parentheses around arrow functions that return object literals.

Input

useFactory: () => ({ showMenu: signal(true) })

Output

useFactory: () => { showMenu: signal(true) }

That changes the meaning of the code. The braces become a block with a label instead of an object literal, so the function returns undefined.

Expected

useFactory: () => ({ showMenu: signal(true) })

Where we see it

Angular compiled output that goes through the OXC pipeline. This ends up breaking DI factories.

Quick pattern

Looks like transforms that produce something like:

=> {identifier:

instead of

=> ({identifier:

Temporary workaround

We currently patch the output before esbuild runs:

const ARROW_OBJ_REGEX = /=>\s*\{(\w+)\s*:/g;

and wrap the object.

Summary

OXC removes required parentheses for arrow functions returning object literals, which changes semantics.