wp-includes/l10n/class-wp-translation-file.php:285Imports translations from another file.
$sourceWP_Translation_Filebool protected function import( WP_Translation_File $source ): bool { if ( null !== $source->error() ) { return false; } $this->headers = $source->headers(); $this->entries = $source->entries(); $this->error = $source->error(); return null === $this->error; }Introduced in 6.5.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/l10n/class-wp-translation-file.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.