Subject: 29.0.50; Narrow to defun fails with Javascript async functions

From: Matthias Meulien <[email-masked]>
Date: Wed, 17 Nov 2021 21:11:35 +0100

1. Create a buffer and enable `js-mode' in that buffer
2. Enter the following function definition:

async function test_async() {
  return true;
}

3. Move cursor past the "f" of the "function" keyword.

4. Call `narrow-to-defun' (C-x n d) and observe that the buffer now
displays the following:

function test_async() {
    // nothing to do
}

This is wrong (async has disappeared).

In GNU Emacs 29.0.50 (build 3, x86_64-pc-linux-gnu, GTK+ Version 3.24.24, cairo version 1.16.0)
 of 2021-11-14 built on carbon
Repository revision: 2ff42ad0e8468a5979a8c5db90333d9c2949bd2e
Repository branch: dev/mm
Windowing system distributor 'The X.Org Foundation', version 11.0.12011000
System Description: Debian GNU/Linux 11 (bullseye)

Configured using:
 'configure --with-native-compilation'

Configured features:
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Load-path shadows:
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