Provide support for non standard WordPress versions

Bug Description

As raised by one user in the support forums PHP warnings can be found if using a non standard WordPress version number (ie. An integer, version 42),

In the users case their WordPress version was changed to 42 after applying an option within their Digital Ocean droplet, with other hosting providers also offering similar features.

The errors appear as below. They don’t impact Site Kit operations or functionality:

wp-content/plugins/google-site-kit/includes/Core/Assets/Assets.php:348
Google\S\C\A\Assets->Google\S\C\A\{closure}()
Unknown location
Google\S\C\A\Script_Data->Google\S\C\A\{closure}()
Unknown location
Google\S\C\A\Asset->before_print()
wp-content/plugins/google-site-kit/includes/Core/Assets/Assets.php:903
Google\S\C\A\Assets->run_before_print_callbacks()
wp-content/plugins/google-site-kit/includes/Core/Assets/Assets.php:912
Google\S\C\A\Assets->run_before_print_callbacks()
wp-content/plugins/google-site-kit/includes/Core/Assets/Assets.php:159
Google\S\C\A\Assets->Google\S\C\A\{closure}()
wp-includes/class-wp-hook.php:307
do_action('admin_print_scripts')
wp-admin/admin-header.php:146

Steps to reproduce

1. Hide your WP version using a security plugin, custom function or hosting control panel
2. Setup Site Kit
3. Enable error reporting
4. Check your error logs

Additional Context

• Site Kit 1.70.0
• Support topic SH info - No obvious cause

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Acceptance criteria

• Site Kit should not assume that the WordPress version has a major and minor segment. While this is commonly the case, version numbers like 5 are still valid version numbers. While this isn’t used by WordPress itself, there are some obscure plugins that change the WordPress version “for security reasons” to one without any . in it, which is currently causing a PHP notice.
• Specifically, the Authentication::inline_js_base_data() method should be adjusted to account for this. If no . is present, it should simply assume 0 for the minor version instead of splitting the version string into major and minor bit.

Implementation Brief

• Update the version which is split by periods in Authentication::inline_js_base_data to be unconditionally concatenated with a trailing .0 so that there are always at least two segments (assuming a non-empty version number)
  • This way, the $major and $minor versions remain accurate and 0 is used as a fallback in the case that the input $version is a single number/integer while preserving the real $version in the base data

Test Coverage

• Add a test to AuthenticationTest to cover a standard case as well as a non-standard WP version by filtering bloginfo

QA Brief

• Follow steps to reproduce and hide the WP version (a plugin like Sucuri can be used).
• See that there’s no longer an error.

Changelog entry

• Fix authentication issue with WordPress security plugins/other plugins that modify/obscure the WordPress version number.

[aaemnnosttv]

@wpdarren For QA, I created a mini plugin to change the version to the integer 42. This shows the problem should be solved but I’ll include it here for others to verify as well. override-wp-version.0.1.zip

[jamesozzie]

I’ll perform a check on this later today and let you know. There are a few ways to hide WP version numbers. Thanks @mohitwp and @wpdarren.