[v6] Inconsistent behaviour of dynamic IDs in JS/JSX macros

[mogelbrod]

Description

While working on #2514 I became aware of a potential bug/discrepancy in how Lingui processes dynamic IDs between JS Macros and JSX Macros:

1. JS Macros (t({ id: dynId, message: "Welcome" })):
   Preserves the dynamic AST node dynId in the output because Babel processes object properties directly. The output retains "id": dynId.
2. JSX Macros (<Trans id={dynId}>Hello</Trans>):
   The dynamic attribute is lost. maybeNodeValue() inside macroJsx.ts evaluates non-static JSX attributes to null. It strips the attribute, completely drops dynId, and instead relies on the hash fallback identifier from the text.

I'm not sure what the expected behaviour is but figured I'd surface this in case it's a bug.

Example test snapshot

import { Trans } from "@lingui/react/macro";
const dynId = "dynamic";
<Trans id={dynId}>Hello</Trans>;

↓ ↓ ↓ ↓ ↓ ↓

import { Trans as _Trans } from "@lingui/react";
const dynId = "dynamic";
<_Trans
  {
    /*i18n*/
    ...{
      id: "uzTaYi",
      message: "Hello",
    }
  }
/>;

Verifications

• I've checked the docs and this isn't covered there.
• I've searched existing issues on GitHub.

Macro Support

Babel with babel-macro-plugin

Lingui Version

6.0.0-next.3

[timofei-iatsenko]

I believe the expected - is to keep an explicit id. However this is very edge case. Because basically passing a variable as id for macro is a misuse