diff --git a/core/modules/locale/locale.module b/core/modules/locale/locale.module
index 3667f93..78a25e7 100644
--- a/core/modules/locale/locale.module
+++ b/core/modules/locale/locale.module
@@ -257,13 +257,13 @@ function locale_translatable_language_list() {
  *
  * The index is computed from the formula of this language.
  *
- * @param $count
+ * @param int $count
  *   Number to return plural for.
- * @param $langcode
- *   Optional language code to translate to a language other than
- *   what is used to display the page.
+ * @param string|null $langcode
+ *   (optional) Language code to translate to a language other than what is used
+ *   to display the page, or NULL for current language. Defaults to NULL.
  *
- * @return
+ * @return int
  *   The numeric index of the plural variant to use for this $langcode and
  *   $count combination or -1 if the language was not found or does not have a
  *   plural formula.
@@ -1029,9 +1029,6 @@ function _locale_strip_quotes($string) {
  * @param string $filepath
  *   File name to parse.
  *
- * @return array
- *   Array of string objects to update indexed by context and source.
- *
  * @throws Exception
  *   If a non-local file is attempted to be parsed.
  */
@@ -1133,10 +1130,11 @@ function _locale_parse_js_file($filepath) {
  * files are rebuilt (with locale_update_js_files()) the next time a
  * request is served in that language.
  *
- * @param $langcode
- *   The language code for which the file needs to be refreshed.
+ * @param string|null $langcode
+ *   (optional) The language code for which the file needs to be refreshed, or
+ *   NULL to refresh all languages. Defaults to NULL.
  *
- * @return
+ * @return array
  *   New content of the 'system.javascript_parsed' variable.
  */
 function _locale_invalidate_js($langcode = NULL) {
@@ -1161,8 +1159,9 @@ function _locale_invalidate_js($langcode = NULL) {
 /**
  * (Re-)Creates the JavaScript translation file for a language.
  *
- * @param $langcode
- *   The language, the translation file should be (re)created for.
+ * @param string|null $langcode
+ *   (optional) The language that the translation file should be (re)created
+ *   for, or NULL for the current language. Defaults to NULL.
  *
  * @return bool
  *   TRUE if translation file exists, FALSE otherwise.
diff --git a/core/modules/locale/src/LocaleConfigSubscriber.php b/core/modules/locale/src/LocaleConfigSubscriber.php
index 6c42d50..304dddd 100644
--- a/core/modules/locale/src/LocaleConfigSubscriber.php
+++ b/core/modules/locale/src/LocaleConfigSubscriber.php
@@ -119,7 +119,7 @@ public function onDelete(LanguageConfigOverrideCrudEvent $event) {
    *
    * @param \Drupal\language\Config\LanguageConfigOverrideCrudEvent $event
    *   The language configuration event.
-   * @param $callable
+   * @param callable $callable
    *   A callable to apply to each translatable string of the configuration.
    */
   protected function updateTranslationStrings(LanguageConfigOverrideCrudEvent $event, $callable) {
diff --git a/core/modules/locale/src/Tests/LocaleConfigSubscriberTest.php b/core/modules/locale/src/Tests/LocaleConfigSubscriberTest.php
index f3f7415..aff3b09 100644
--- a/core/modules/locale/src/Tests/LocaleConfigSubscriberTest.php
+++ b/core/modules/locale/src/Tests/LocaleConfigSubscriberTest.php
@@ -317,11 +317,11 @@ protected function deleteLocaleTranslationData($config_name, $key, $source_value
   /**
    * Ensures configuration was saved correctly.
    *
-   * @param $config_name
+   * @param string $config_name
    *   The configuration name.
-   * @param $key
+   * @param string $key
    *   The configuration key.
-   * @param $value
+   * @param mixed $value
    *   The configuration value.
    *
    * @return bool