update for code review comment #20

src/Plugin/Field/FieldFormatter/SubstrFormatter.php

@@ -30,7 +30,7 @@ class SubstrFormatter extends FormatterBase {
    */
   public static function defaultSettings() {
     return [
-      'trim_start' => t('2'),
+      'trim_start' => 2,
       'trim_length' => NULL,
     ] + parent::defaultSettings();
   }
@@ -41,14 +41,14 @@ class SubstrFormatter extends FormatterBase {
   public function settingsForm(array $form, FormStateInterface $form_state) {
     $element['trim_start'] = [
       '#type'          => 'textfield',
-      '#title'         => $this->t('Trim Start Position:'),
+      '#title'         => $this->t('Trim Start Position'),
       '#description'   => $this->t('A negative value will trim all characters from the start of the string until the specified character count from the end of the string (trimming from the left), a positive value will do the opposite and trim from the right. For the string 12345678, -3 would output 678 and 3 would output 123.'),
       '#default_value' => $this->getSetting('trim_start'),
     ];
 
     $element['trim_length'] = [
       '#type'          => 'textfield',
-      '#title'         => $this->t('Trimmed String Length (Optional):'),
+      '#title'         => $this->t('Trimmed String Length (Optional)'),
       '#description'   => $this->t('Sets the string length to a fixed number of characters. For the string 12345678, with a start position of -3, a trim length of 2 would output 67.'),
       '#default_value' => $this->getSetting('trim_length'),
     ];
@@ -64,16 +64,17 @@ class SubstrFormatter extends FormatterBase {
     $settings = $this->getSettings();
 
     if (!empty($settings['trim_start']) and !empty($settings['trim_length'])) {
-      $summary[] = $this->t(
-          'Display only @trim_length character(s) from the start position of @trim_start in the string.',
-          ['@trim_start' => $settings['trim_start'], '@trim_length' => $settings['trim_length']],
-        );
+      $summary[] = $this->formatPlural($settings['trim_length'],
+        'Display only @trim_length character from the start position of @trim_start in the string.',
+        'Display only @trim_length characters from the start position of @trim_start in the string.',
+        ['@trim_start' => $settings['trim_start'], '@trim_length' => $settings['trim_length']],
+      );
     }
     elseif (!empty($settings['trim_start']) and empty($settings['trim_length'])) {
       $summary[] = $this->t(
-        'Display all character(s) from the start position of @trim_start in the string.',
+        'Display all characters from the start position of @trim_start in the string.',
         ['@trim_start' => $settings['trim_start']],
-          );
+      );
     }
     else {
       $summary[] = $this->t('No trimming will occur.');