wp-includes/load.php:1520Attempts an early load of translations.
function wp_load_translations_early() { global $wp_textdomain_registry, $wp_locale; static $loaded = false; if ( $loaded ) { return; } $loaded = true; if ( function_exists( 'did_action' ) && did_action( 'init' ) ) { return; } // We need $wp_local_package. require ABSPATH . WPINC . '/version.php'; // Translation and localization. require_once ABSPATH . WPINC . '/pomo/mo.php'; require_once ABSPATH . WPINC . '/l10n/class-wp-translation-controller.php'; require_once ABSPATH . WPINC . '/l10n/class-wp-translations.php'; require_once ABSPATH . WPINC . '/l10n/class-wp-translation-file.php'; require_once ABSPATH . WPINC . '/l10n/class-wp-translation-file-mo.php'; require_once ABSPATH . WPINC . '/l10n/class-wp-translation-file-php.php'; require_once ABSPATH . WPINC . '/l10n.php'; require_once ABSPATH . WPINC . '/class-wp-textdomain-registry.php'; require_once ABSPATH . WPINC . '/class-wp-locale.php'; require_once ABSPATH . WPINC . '/class-wp-locale-switcher.php'; // General libraries. require_once ABSPATH . WPINC . '/plugin.php'; $locales = array(); $locations = array(); if ( ! $wp_textdomain_registry instanceof WP_Textdomain_Registry ) { $wp_textdomain_registry = new WP_Textdomain_Registry(); } while ( true ) { if ( defined( 'WPLANG' ) ) { if ( '' === WPLANG ) { break; } $locales[] = WPLANG; } if ( isset( $wp_local_package ) ) { $locales[] = $wp_local_package; } if ( ! $locales ) { break; } if ( defined( 'WP_LANG_DIR' ) && @is_dir( WP_LANG_DIR ) ) { $locations[] = WP_LANG_DIR; } if ( defined( 'WP_CONTENT_DIR' ) && @is_dir( WP_CONTENT_DIR . '/languages' ) ) { $locations[] = WP_CONTENT_DIR . '/languages'; } if ( @is_dir( ABSPATH . 'wp-content/languages' ) ) { $locations[] = ABSPATH . 'wp-content/languages'; } if ( @is_dir( ABSPATH . WPINC . '/languages' ) ) { $locations[] = ABSPATH . WPINC . '/languages'; } if ( ! $locations ) { break; } $locations = array_unique( $locations ); foreach ( $locales as $locale ) { foreach ( $locations as $location ) { if ( file_exists( $location . '/' . $locale . '.mo' ) ) {Introduced in 3.4.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/load.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.