WordPress at a glance
filter is not described

plugin_locale filter-hook . WP 3.0.0

Filters a plugin's locale.

Usage

add_filter( 'plugin_locale', 'filter_function_name_378', 10, 2 );
function filter_function_name_378( $locale, $domain ){
	// filter...

	return $locale;
}
$locale(string)
The plugin's current locale.
$domain(string)
Text domain. Unique identifier for retrieving translated strings.

Where the hook is called

load_plugin_textdomain()
WooCommerce::load_plugin_textdomain()
load_muplugin_textdomain()
wp-includes/l10n.php 762
$locale = apply_filters( 'plugin_locale', determine_locale(), $domain );
woocommerce/includes/class-woocommerce.php 517
$locale = apply_filters( 'plugin_locale', $locale, 'woocommerce' );
wp-includes/l10n.php 796
$locale = apply_filters( 'plugin_locale', determine_locale(), $domain );

Where the hook is used (in WP core)

Does not used.