Reusable blocks are displayed as unsupported (development mode only)

[fluiddot]

Description

After recent changes (probably related to the RN 0.64 upgrade), the reusable block is displayed as unsupported even when the block is available.

Step-by-step reproduction instructions

1. Use a debug version that connects to the Metro server.
2. Open a post/page that contains a reusable block.
3. Observe that the block is displayed as unsupported.

Expected behaviour

The reusable block should be available in WP.com sites.

Actual behaviour

The reusable block is not available.

Screenshots or screen recording (optional)

WordPress information

• WordPress version: N/A
• Gutenberg version: N/A
• Are all plugins except Gutenberg deactivated? N/A
• Are you using a default theme (e.g. Twenty Twenty-One)? N/A

Device information

• Device: iPhone 8 (simulator)
• Operating system: iOS 14.2
• WordPress app version: 779bb171e889ad527cc1c311675119e6596e0127

[fluiddot]

I noticed that this issue is not happening in a recent build that points to the Gutenberg commit referenced in the description (WordPress iOS installable build) so in production, this issue can't be reproduced. Nevertheless, I'd like to investigate this further as it might be covering actual errors.

[fluiddot]

After further investigation, I find out that this issue is caused because the native.pre-render WP hook is called multiple times, in fact, it gets called for every warning and error that happens during the initialization. The first call to the hook is ok but the consecutive ones are passing the props empty, here you can check the screenshots from a debugging session:

First call - includes props:

Second call - doesn't include props:

The warning that produces the above call is produced when calling setupLocale which imports modules that contain circular dependencies.

Warning:

Require cycle: gutenberg/packages/block-library/src/index.native.js -> gutenberg/packages/block-library/src/latest-posts/index.js -> gutenberg/packages/block-library/src/latest-posts/edit.native.js -> gutenberg/packages/block-library/src/index.native.js\n\nRequire cycles are allowed, but can result in uninitialized values. Consider refactoring to remove the need for a cycle.