utf8mb4_convert-default-db.diff

diff --git a/utf8mb4_convert.drush.inc b/utf8mb4_convert.drush.inc
index de647d0..9a0e66a 100644
--- a/utf8mb4_convert.drush.inc
+++ b/utf8mb4_convert.drush.inc
@@ -225,16 +225,25 @@ function utf8mb4_convert_drush_command() {
   $items['utf8mb4-convert-databases'] = array(
     'description' => "Converts all databases defined in settings.php to utf8mb4.",
     'bootstrap' => DRUSH_BOOTSTRAP_DRUPAL_FULL,
+    'arguments' => array(
+      'connections' => 'A space separated list of connections. Default is default connection.',
+    ),
     'options' => array(
       'collation' => 'Specify a collation. Default is "utf8mb4_general_ci", sites with content that is outside of Latin 1 characters may want to use "utf8mb4_unicode_ci".',
       'charset' => 'Specify a charset. Default is "utf8mb4".',
-    )
+    ),
+    'examples' => array(
+      'drush utf8mb4-convert-databases' => 'Convert the default database.',
+      'drush utf8mb4-convert-databases default' => 'Convert the default database (same as no argument).',
+      'drush utf8mb4-convert-databases default site2 site3' => 'Convert all specified databases.',
+    ),
+    'aliases' => array('mb4c'),
   );

   return $items;
 }

-function drush_utf8mb4_convert_databases() {
+function drush_utf8mb4_convert_databases($connections_input = NULL) {
   $charset = drush_get_option('charset', 'utf8mb4');
   $collation = drush_get_option('collation', 'utf8mb4_general_ci');
   global $databases;
@@ -242,11 +251,29 @@ function drush_utf8mb4_convert_databases() {
     drush_print('Please install Drupal 7.50 or above prior to running this script.');
     return;
   }
-  if (!drush_confirm('This will convert all databases defined in settings.php to utf8mb4. Back up your databases before continuing! Continue?')) {
+
+  // Default to the default DB connection, else use the user input.
+  if (empty($connections_input)) {
+    $connections['default'] = $databases['default'];
+  }
+  else {
+    $connections_list = array();
+    // Dump the module name in the first position.
+    drush_shift();
+    // Get the rest, array_intersect_key needs an associative array for the keys.
+    while ($arg = drush_shift()) {
+      $connections_list[$arg] = '';
+    }
+    $connections = array_intersect_key($databases, $connections_list);
+  }
+
+  drush_print(dt('This will convert the following databases to utf8mb4: !connections', array('!connections' => implode(', ', array_keys($connections)))));
+  if (!drush_confirm('Back up your databases before continuing! Continue?')) {
     return;
   }
+
   $converter = new DrupalCharsetConverter($charset, $collation);
-  $success = $converter->convert($databases);
+  $success = $converter->convert($connections);
   // Prevent the hook_requirements() check from telling us to convert the
   // database to utf8mb4.
   if ($success) {