only in patch2:
unchanged:
--- a/bookable_calendar.install
+++ b/bookable_calendar.install
@@ -31,8 +31,8 @@ function bookable_calendar_requirements($phase) {
   if ($phase == 'runtime') {
     $value = mt_rand(0, 100);
     $requirements['bookable_calendar_status'] = [
-      'title' => t('Bookable Calendar status'),
-      'value' => t('Bookable Calendar value: @value', ['@value' => $value]),
+      'title' => $this->t('Bookable Calendar status'),
+      'value' => $this->t('Bookable Calendar value: @value', ['@value' => $value]),
       'severity' => $value > 50 ? REQUIREMENT_INFO : REQUIREMENT_WARNING,
     ];
   }
@@ -59,8 +59,8 @@ function bookable_calendar_update_8102() {
   $field_storage_definition = BaseFieldDefinition::create('text_long')
     ->setRevisionable(TRUE)
     ->setTranslatable(TRUE)
-    ->setLabel(t('Success message'))
-    ->setDescription(t('Message displayed after a sucessful registration.'));
+    ->setLabel($this->t('Success message'))
+    ->setDescription($this->t('Message displayed after a sucessful registration.'));
   \Drupal::entityDefinitionUpdateManager()
     ->installFieldStorageDefinition('success_message', 'bookable_calendar', 'bookable_calendar', $field_storage_definition);
 }
@@ -71,8 +71,8 @@ function bookable_calendar_update_8102() {
 function bookable_calendar_update_8103() {
   $field_storage_definition = BaseFieldDefinition::create('boolean')
     ->setRevisionable(TRUE)
-    ->setLabel(t('Treat Slots as Parties'))
-    ->setDescription(t('This will change the math of "Max Slots" to "Max Parties". This will allow you to only have 3 different groups claim a slot but each group can have as big of a party as your Max Party Size limit.'))
+    ->setLabel($this->t('Treat Slots as Parties'))
+    ->setDescription($this->t('This will change the math of "Max Slots" to "Max Parties". This will allow you to only have 3 different groups claim a slot but each group can have as big of a party as your Max Party Size limit.'))
     ->setDefaultValue(FALSE)
     ->setSetting('on_label', 'Treat Slots as Parties');
   \Drupal::entityDefinitionUpdateManager()
@@ -84,21 +84,21 @@ function bookable_calendar_update_8103() {
  */
 function bookable_calendar_update_8104() {
   $field_storage_definition = BaseFieldDefinition::create('boolean')
-    ->setLabel(t('Override Default User Email'))
-    ->setDescription(t('Text in the email is editable on the main settings page, if you want different text per calendar you will need to select this'));
+    ->setLabel($this->t('Override Default User Email'))
+    ->setDescription($this->t('Text in the email is editable on the main settings page, if you want different text per calendar you will need to select this'));
   \Drupal::entityDefinitionUpdateManager()
     ->installFieldStorageDefinition('notification_email_override', 'bookable_calendar', 'bookable_calendar', $field_storage_definition);
 
   $field_storage_definition = BaseFieldDefinition::create('string')
-    ->setLabel(t('User Email Subject'))
-    ->setDescription(t('The subject of the email sent to the user if Override Default User Email is set'))
+    ->setLabel($this->t('User Email Subject'))
+    ->setDescription($this->t('The subject of the email sent to the user if Override Default User Email is set'))
     ->setSetting('max_length', 255);
   \Drupal::entityDefinitionUpdateManager()
     ->installFieldStorageDefinition('notification_email_subject', 'bookable_calendar', 'bookable_calendar', $field_storage_definition);
 
   $field_storage_definition = BaseFieldDefinition::create('text_long')
-    ->setLabel(t('User Email Body'))
-    ->setDescription(t('The body of the email sent to the user if Override Default User Email is set'));
+    ->setLabel($this->t('User Email Body'))
+    ->setDescription($this->t('The body of the email sent to the user if Override Default User Email is set'));
   \Drupal::entityDefinitionUpdateManager()
   ->installFieldStorageDefinition('notification_email_body', 'bookable_calendar', 'bookable_calendar', $field_storage_definition);
 }
@@ -108,8 +108,8 @@ function bookable_calendar_update_8104() {
  */
 function bookable_calendar_update_8105() {
   $field_storage_definition = BaseFieldDefinition::create('boolean')
-    ->setLabel(t('Checked In'))
-    ->setDescription(t('Whether or not this user has showed up to their booked event'))
+    ->setLabel($this->t('Checked In'))
+    ->setDescription($this->t('Whether or not this user has showed up to their booked event'))
     ->setDefaultValue(FALSE);
   \Drupal::entityDefinitionUpdateManager()
     ->installFieldStorageDefinition('checked_in', 'booking_contact', 'booking_contact', $field_storage_definition);
@@ -120,8 +120,8 @@ function bookable_calendar_update_8105() {
  */
 function bookable_calendar_update_8106() {
   $field_storage_definition = BaseFieldDefinition::create('integer')
-    ->setLabel(t('Slots'))
-    ->setDescription(t('The number of available slots for this instance. If empty (NB not zero), will use calendar\'s defaults.'))
+    ->setLabel($this->t('Slots'))
+    ->setDescription($this->t('The number of available slots for this instance. If empty (NB not zero), will use calendar\'s defaults.'))
     ->setCardinality(1)
     ->setDefaultValue(NULL);
   \Drupal::entityDefinitionUpdateManager()
only in patch2:
unchanged:
--- a/src/Entity/BookableCalendar.php
+++ b/src/Entity/BookableCalendar.php
@@ -111,8 +111,8 @@ class BookableCalendar extends RevisionableContentEntityBase implements Bookable
     $fields['title'] = BaseFieldDefinition::create('string')
       ->setRevisionable(TRUE)
       ->setTranslatable(TRUE)
-      ->setLabel(t('Title'))
-      ->setDescription(t('The title of the bookable calendar entity.'))
+      ->setLabel($this->t('Title'))
+      ->setDescription($this->t('The title of the bookable calendar entity.'))
       ->setRequired(TRUE)
       ->setSetting('max_length', 255)
       ->setDisplayOptions('form', [
@@ -130,8 +130,8 @@ class BookableCalendar extends RevisionableContentEntityBase implements Bookable
     $fields['description'] = BaseFieldDefinition::create('text_long')
       ->setRevisionable(TRUE)
       ->setTranslatable(TRUE)
-      ->setLabel(t('Description'))
-      ->setDescription(t('A description of the bookable calendar.'))
+      ->setLabel($this->t('Description'))
+      ->setDescription($this->t('A description of the bookable calendar.'))
       ->setDisplayOptions('form', [
         'type' => 'text_textarea',
         'weight' => -9,
@@ -147,8 +147,8 @@ class BookableCalendar extends RevisionableContentEntityBase implements Bookable
     $fields['success_message'] = BaseFieldDefinition::create('text_long')
       ->setRevisionable(TRUE)
       ->setTranslatable(TRUE)
-      ->setLabel(t('Success message'))
-      ->setDescription(t('Message displayed after a sucessful registration.'))
+      ->setLabel($this->t('Success message'))
+      ->setDescription($this->t('Message displayed after a sucessful registration.'))
       ->setDisplayOptions('form', [
         'type' => 'text_textarea',
         'weight' => -8,
@@ -157,8 +157,8 @@ class BookableCalendar extends RevisionableContentEntityBase implements Bookable
       ->setDisplayConfigurable('view', FALSE);
 
     $fields['notification_email'] = BaseFieldDefinition::create('boolean')
-      ->setLabel(t('User Notification Email'))
-      ->setDescription(t('If enabled users will get a notification email when they book an opening.'))
+      ->setLabel($this->t('User Notification Email'))
+      ->setDescription($this->t('If enabled users will get a notification email when they book an opening.'))
       ->setDefaultValue(TRUE)
       ->setDisplayOptions('form', [
         'type' => 'boolean_checkbox',
@@ -171,8 +171,8 @@ class BookableCalendar extends RevisionableContentEntityBase implements Bookable
       ->setDisplayConfigurable('view', FALSE);
 
     $fields['notification_email_override'] = BaseFieldDefinition::create('boolean')
-      ->setLabel(t('Override Default User Email'))
-      ->setDescription(t('Text in the email is editable on the main settings page, if you want different text per calendar you will need to select this'))
+      ->setLabel($this->t('Override Default User Email'))
+      ->setDescription($this->t('Text in the email is editable on the main settings page, if you want different text per calendar you will need to select this'))
       ->setDisplayOptions('form', [
         'type' => 'boolean_checkbox',
         'settings' => [
@@ -184,8 +184,8 @@ class BookableCalendar extends RevisionableContentEntityBase implements Bookable
       ->setDisplayConfigurable('view', FALSE);
 
     $fields['notification_email_subject'] = BaseFieldDefinition::create('string')
-      ->setLabel(t('User Email Subject'))
-      ->setDescription(t('The subject of the email sent to the user if Override Default User Email is set'))
+      ->setLabel($this->t('User Email Subject'))
+      ->setDescription($this->t('The subject of the email sent to the user if Override Default User Email is set'))
       ->setSetting('max_length', 255)
       ->setDisplayOptions('form', [
         'type' => 'string_textfield',
@@ -194,8 +194,8 @@ class BookableCalendar extends RevisionableContentEntityBase implements Bookable
       ->setDisplayConfigurable('form', TRUE);
 
     $fields['notification_email_body'] = BaseFieldDefinition::create('text_long')
-      ->setLabel(t('User Email Body'))
-      ->setDescription(t('The body of the email sent to the user if Override Default User Email is set'))
+      ->setLabel($this->t('User Email Body'))
+      ->setDescription($this->t('The body of the email sent to the user if Override Default User Email is set'))
       ->setDisplayOptions('form', [
         'type' => 'text_textarea',
         'weight' => -5,
@@ -203,8 +203,8 @@ class BookableCalendar extends RevisionableContentEntityBase implements Bookable
       ->setDisplayConfigurable('form', TRUE);
 
     $fields['admin_notification_email'] = BaseFieldDefinition::create('boolean')
-      ->setLabel(t('Admin Notification Emails'))
-      ->setDescription(t('If enabled admins will get a notification email on each booking.'))
+      ->setLabel($this->t('Admin Notification Emails'))
+      ->setDescription($this->t('If enabled admins will get a notification email on each booking.'))
       ->setDefaultValue(TRUE)
       ->setDisplayOptions('form', [
         'type' => 'boolean_checkbox',
@@ -217,8 +217,8 @@ class BookableCalendar extends RevisionableContentEntityBase implements Bookable
       ->setDisplayConfigurable('view', FALSE);
 
     $fields['notify_email_recipient_role'] = BaseFieldDefinition::create('entity_reference')
-      ->setLabel(t('Notification Email Recipient Role'))
-      ->setDescription(t('Send email notifications on bookings to the following roles.'))
+      ->setLabel($this->t('Notification Email Recipient Role'))
+      ->setDescription($this->t('Send email notifications on bookings to the following roles.'))
       ->setCardinality(FieldStorageDefinitionInterface::CARDINALITY_UNLIMITED)
       ->setSettings([
         'target_type' => 'user_role'
@@ -236,8 +236,8 @@ class BookableCalendar extends RevisionableContentEntityBase implements Bookable
       ->setDisplayConfigurable('view', FALSE);
 
     $fields['notify_email_recipients'] = BaseFieldDefinition::create('email')
-      ->setLabel(t('Notification Email Recipients'))
-      ->setDescription(t('The email address, or addresses one per line to receive the emails on bookings.'))
+      ->setLabel($this->t('Notification Email Recipients'))
+      ->setDescription($this->t('The email address, or addresses one per line to receive the emails on bookings.'))
       ->setCardinality(FieldStorageDefinitionInterface::CARDINALITY_UNLIMITED)
       ->setDisplayOptions('form', [
         'type' => 'email_default',
@@ -252,8 +252,8 @@ class BookableCalendar extends RevisionableContentEntityBase implements Bookable
       ->setDisplayConfigurable('view', FALSE);
 
     $fields['max_party_size'] = BaseFieldDefinition::create('integer')
-      ->setLabel(t('Max Party Size'))
-      ->setDescription(t('What is the largest amount of bookings a single user can claim per opening. This limits a single user from claiming all 10 to themselves.'))
+      ->setLabel($this->t('Max Party Size'))
+      ->setDescription($this->t('What is the largest amount of bookings a single user can claim per opening. This limits a single user from claiming all 10 to themselves.'))
       ->setDisplayOptions('form', [
         'type' => 'number',
         'settings' => [
@@ -265,8 +265,8 @@ class BookableCalendar extends RevisionableContentEntityBase implements Bookable
       ->setDisplayConfigurable('view', FALSE);
 
     $fields['slots_per_opening'] = BaseFieldDefinition::create('integer')
-      ->setLabel(t('Slots Per Opening'))
-      ->setDescription(t("The amount of Bookings that can claim a single opening. For example if your event has hour long openings you let people register for and you can handle 10 people per hour set this field to '10.'"))
+      ->setLabel($this->t('Slots Per Opening'))
+      ->setDescription($this->t("The amount of Bookings that can claim a single opening. For example if your event has hour long openings you let people register for and you can handle 10 people per hour set this field to '10.'"))
       ->setRequired(TRUE)
       ->setDefaultValue(1)
       ->setDisplayOptions('form', [
@@ -281,8 +281,8 @@ class BookableCalendar extends RevisionableContentEntityBase implements Bookable
 
     $fields['slots_as_parties'] = BaseFieldDefinition::create('boolean')
       ->setRevisionable(TRUE)
-      ->setLabel(t('Treat Slots as Parties'))
-      ->setDescription(t('This will change the math of "Max Slots" to "Max Parties". This will allow you to only have 3 different groups claim a slot but each group can have as big of a party as your Max Party Size limit.'))
+      ->setLabel($this->t('Treat Slots as Parties'))
+      ->setDescription($this->t('This will change the math of "Max Slots" to "Max Parties". This will allow you to only have 3 different groups claim a slot but each group can have as big of a party as your Max Party Size limit.'))
       ->setDefaultValue(FALSE)
       ->setSetting('on_label', 'Treat Slots as Parties')
       ->setDisplayOptions('form', [
@@ -296,8 +296,8 @@ class BookableCalendar extends RevisionableContentEntityBase implements Bookable
       ->setDisplayConfigurable('view', FALSE);
 
     $fields['booking_future_time'] = BaseFieldDefinition::create('string')
-      ->setLabel(t('Booking Future Time'))
-      ->setDescription(t('How far in the future from now are people allowed to register,
+      ->setLabel($this->t('Booking Future Time'))
+      ->setDescription($this->t('How far in the future from now are people allowed to register,
         this would stop people from registering for events over a month away. An offset from the current
         time such as "+ 1 day" "+ 1 month" or "+ 1 year" using
         <a href="https://www.php.net/manual/en/function.strtotime.php">php strtotime</a>.'))
@@ -310,8 +310,8 @@ class BookableCalendar extends RevisionableContentEntityBase implements Bookable
       ->setDisplayConfigurable('view', FALSE);
 
     $fields['booking_lead_time'] = BaseFieldDefinition::create('string')
-      ->setLabel(t('Booking Lead Time'))
-      ->setDescription(t('How close to now are people allowed to register,
+      ->setLabel($this->t('Booking Lead Time'))
+      ->setDescription($this->t('How close to now are people allowed to register,
         this would stop people from registering for same day events.
         An offset from the current time such as "now" "+ 15 minutes" or "+ 1 day" using
         <a href="https://www.php.net/manual/en/function.strtotime.php">php strtotime</a>.'))
@@ -326,8 +326,8 @@ class BookableCalendar extends RevisionableContentEntityBase implements Bookable
       ->setDisplayConfigurable('view', FALSE);
 
     $fields['calendar_openings'] = BaseFieldDefinition::create('entity_reference')
-      ->setLabel(t('Calendar Openings'))
-      ->setDescription(t('The Openings for this Calendar.'))
+      ->setLabel($this->t('Calendar Openings'))
+      ->setDescription($this->t('The Openings for this Calendar.'))
       ->setCardinality(FieldStorageDefinitionInterface::CARDINALITY_UNLIMITED)
       ->setSettings([
         'target_type' => 'bookable_calendar_opening'
@@ -338,8 +338,8 @@ class BookableCalendar extends RevisionableContentEntityBase implements Bookable
 
     $fields['active'] = BaseFieldDefinition::create('boolean')
       ->setRevisionable(TRUE)
-      ->setLabel(t('Active'))
-      ->setDescription(t('Allows for calendars to be visible but no longer accepting Bookings whether temporary or permanently.'))
+      ->setLabel($this->t('Active'))
+      ->setDescription($this->t('Allows for calendars to be visible but no longer accepting Bookings whether temporary or permanently.'))
       ->setDefaultValue(TRUE)
       ->setSetting('on_label', 'Active')
       ->setDisplayOptions('form', [
@@ -354,8 +354,8 @@ class BookableCalendar extends RevisionableContentEntityBase implements Bookable
 
     $fields['status'] = BaseFieldDefinition::create('boolean')
       ->setRevisionable(TRUE)
-      ->setLabel(t('Status'))
-      ->setDescription(t('A boolean indicating whether the bookable calendar is enabled.
+      ->setLabel($this->t('Status'))
+      ->setDescription($this->t('A boolean indicating whether the bookable calendar is enabled.
         It is different than active as this will hide it from end users instead of just disabling Bookings'))
       ->setDefaultValue(TRUE)
       ->setSetting('on_label', 'Enabled')
only in patch2:
unchanged:
--- a/src/Entity/BookableCalendarOpening.php
+++ b/src/Entity/BookableCalendarOpening.php
@@ -101,8 +101,8 @@ class BookableCalendarOpening extends RevisionableContentEntityBase implements B
     $fields['title'] = BaseFieldDefinition::create('string')
       ->setRevisionable(TRUE)
       ->setTranslatable(TRUE)
-      ->setLabel(t('Title'))
-      ->setDescription(t('The title of the bookable calendar opening entity.'))
+      ->setLabel($this->t('Title'))
+      ->setDescription($this->t('The title of the bookable calendar opening entity.'))
       ->setRequired(TRUE)
       ->setSetting('max_length', 255)
       ->setDisplayOptions('form', [
@@ -119,8 +119,8 @@ class BookableCalendarOpening extends RevisionableContentEntityBase implements B
 
     $fields['status'] = BaseFieldDefinition::create('boolean')
       ->setRevisionable(TRUE)
-      ->setLabel(t('Status'))
-      ->setDescription(t('A boolean indicating whether the bookable calendar opening is enabled.'))
+      ->setLabel($this->t('Status'))
+      ->setDescription($this->t('A boolean indicating whether the bookable calendar opening is enabled.'))
       ->setDefaultValue(TRUE)
       ->setSetting('on_label', 'Enabled')
       ->setDisplayOptions('form', [
@@ -142,9 +142,9 @@ class BookableCalendarOpening extends RevisionableContentEntityBase implements B
       ->setDisplayConfigurable('view', TRUE);
 
     $fields['bookable_calendar'] = BaseFieldDefinition::create('entity_reference')
-      ->setLabel(t('Bookable Calendar'))
+      ->setLabel($this->t('Bookable Calendar'))
       ->setRequired(TRUE)
-      ->setDescription(t('The calendar this Opening Belongs to'))
+      ->setDescription($this->t('The calendar this Opening Belongs to'))
       ->setCardinality(1)
       ->setSettings([
         'target_type' => 'bookable_calendar'
@@ -170,8 +170,8 @@ class BookableCalendarOpening extends RevisionableContentEntityBase implements B
       ->setDisplayConfigurable('view', TRUE);
 
     $fields['booking_instance'] = BaseFieldDefinition::create('entity_reference')
-      ->setLabel(t('Booking Instance'))
-      ->setDescription(t('The Opening Instances for this Opening.'))
+      ->setLabel($this->t('Booking Instance'))
+      ->setDescription($this->t('The Opening Instances for this Opening.'))
       ->setCardinality(FieldStorageDefinitionInterface::CARDINALITY_UNLIMITED)
       ->setSettings([
         'target_type' => 'bookable_calendar_opening_inst'
@@ -188,8 +188,8 @@ class BookableCalendarOpening extends RevisionableContentEntityBase implements B
       ->setDisplayConfigurable('view', TRUE);
 
     $fields['date'] = BaseFieldDefinition::create('smartdate')
-      ->setLabel(t('Date'))
-      ->setDescription(t('The dates for this opening.'))
+      ->setLabel($this->t('Date'))
+      ->setDescription($this->t('The dates for this opening.'))
       ->setCardinality(FieldStorageDefinitionInterface::CARDINALITY_UNLIMITED)
       ->setRequired(TRUE)
       ->setDefaultValue([
only in patch2:
unchanged:
--- a/src/Entity/BookableCalendarOpeningInstance.php
+++ b/src/Entity/BookableCalendarOpeningInstance.php
@@ -62,8 +62,8 @@ class BookableCalendarOpeningInstance extends ContentEntityBase implements Booka
     $fields = parent::baseFieldDefinitions($entity_type);
 
     $fields['booking'] = BaseFieldDefinition::create('entity_reference')
-      ->setLabel(t('Booking'))
-      ->setDescription(t('Each booking that references this instance.'))
+      ->setLabel($this->t('Booking'))
+      ->setDescription($this->t('Each booking that references this instance.'))
       ->setCardinality(FieldStorageDefinitionInterface::CARDINALITY_UNLIMITED)
       ->setSettings([
         'target_type' => 'booking'
@@ -89,8 +89,8 @@ class BookableCalendarOpeningInstance extends ContentEntityBase implements Booka
       ->setDisplayConfigurable('view', TRUE);
 
     $fields['booking_opening'] = BaseFieldDefinition::create('entity_reference')
-      ->setLabel(t('Booking Opening'))
-      ->setDescription(t('The Opening this Instance points to.'))
+      ->setLabel($this->t('Booking Opening'))
+      ->setDescription($this->t('The Opening this Instance points to.'))
       ->setCardinality(1)
       ->setRequired(TRUE)
       ->setSettings([
@@ -117,8 +117,8 @@ class BookableCalendarOpeningInstance extends ContentEntityBase implements Booka
       ->setDisplayConfigurable('view', TRUE);
 
     $fields['date'] = BaseFieldDefinition::create('smartdate')
-      ->setLabel(t('Date'))
-      ->setDescription(t('The dates for this opening instance.'))
+      ->setLabel($this->t('Date'))
+      ->setDescription($this->t('The dates for this opening instance.'))
       ->setCardinality(1)
       ->setRequired(TRUE)
       ->setDefaultValue([
@@ -139,24 +139,24 @@ class BookableCalendarOpeningInstance extends ContentEntityBase implements Booka
       ->setDisplayConfigurable('view', TRUE);
 
     $fields['available_slots'] = BaseFieldDefinition::create('integer')
-      ->setLabel(t('Available slots'))
-      ->setDescription(t('The available slots for this opening instance.'))
+      ->setLabel($this->t('Available slots'))
+      ->setDescription($this->t('The available slots for this opening instance.'))
       ->setCardinality(1)
       ->setComputed(TRUE)
       ->setClass('\Drupal\bookable_calendar\AvailableSlotsItemList')
       ->setDisplayConfigurable('view', TRUE);
 
     $fields['max_slots'] = BaseFieldDefinition::create('integer')
-      ->setLabel(t('Maximum slots'))
-      ->setDescription(t('The maximum slots for this opening instance.'))
+      ->setLabel($this->t('Maximum slots'))
+      ->setDescription($this->t('The maximum slots for this opening instance.'))
       ->setCardinality(1)
       ->setComputed(TRUE)
       ->setClass('\Drupal\bookable_calendar\MaxSlotsItemList')
       ->setDisplayConfigurable('view', TRUE);
 
     $fields['slots'] = BaseFieldDefinition::create('integer')
-      ->setLabel(t('Slots'))
-      ->setDescription(t('The number of available slots for this instance. If empty (NB not zero), will use calendar\'s defaults.'))
+      ->setLabel($this->t('Slots'))
+      ->setDescription($this->t('The number of available slots for this instance. If empty (NB not zero), will use calendar\'s defaults.'))
       ->setCardinality(1)
       ->setDisplayOptions('form', [
         'type' => 'integer',
only in patch2:
unchanged:
--- a/src/Entity/Booking.php
+++ b/src/Entity/Booking.php
@@ -62,8 +62,8 @@ class Booking extends ContentEntityBase implements BookingInterface {
     $fields = parent::baseFieldDefinitions($entity_type);
 
     $fields['created'] = BaseFieldDefinition::create('created')
-      ->setLabel(t('Authored on'))
-      ->setDescription(t('The time that the booking was created.'))
+      ->setLabel($this->t('Authored on'))
+      ->setDescription($this->t('The time that the booking was created.'))
       ->setDisplayOptions('view', [
         'label' => 'above',
         'type' => 'timestamp',
@@ -77,8 +77,8 @@ class Booking extends ContentEntityBase implements BookingInterface {
       ->setDisplayConfigurable('view', TRUE);
 
     $fields['booking_instance'] = BaseFieldDefinition::create('entity_reference')
-      ->setLabel(t('Booking Instance'))
-      ->setDescription(t('The Opening Instance this Booking is for.'))
+      ->setLabel($this->t('Booking Instance'))
+      ->setDescription($this->t('The Opening Instance this Booking is for.'))
       ->setRequired(TRUE)
       ->setSettings([
         'target_type' => 'bookable_calendar_opening_inst'
@@ -104,8 +104,8 @@ class Booking extends ContentEntityBase implements BookingInterface {
       ->setDisplayConfigurable('view', TRUE);
 
     $fields['booking_calendar'] = BaseFieldDefinition::create('entity_reference')
-      ->setLabel(t('Booking Calendar'))
-      ->setDescription(t('The parent Calendar this Booking is for.'))
+      ->setLabel($this->t('Booking Calendar'))
+      ->setDescription($this->t('The parent Calendar this Booking is for.'))
       ->setRequired(TRUE)
       ->setSettings([
         'target_type' => 'bookable_calendar'
@@ -131,8 +131,8 @@ class Booking extends ContentEntityBase implements BookingInterface {
       ->setDisplayConfigurable('view', TRUE);
 
     $fields['contact'] = BaseFieldDefinition::create('entity_reference')
-      ->setLabel(t('Contact'))
-      ->setDescription(t('The Booking Contact this Booking belongs to.'))
+      ->setLabel($this->t('Contact'))
+      ->setDescription($this->t('The Booking Contact this Booking belongs to.'))
       ->setRequired(TRUE)
       ->setSettings([
         'target_type' => 'booking_contact'
@@ -158,8 +158,8 @@ class Booking extends ContentEntityBase implements BookingInterface {
       ->setDisplayConfigurable('view', TRUE);
 
     $fields['booking_date'] = BaseFieldDefinition::create('smartdate')
-      ->setLabel(t('Booking Date'))
-      ->setDescription(t('The date this booking is for.'))
+      ->setLabel($this->t('Booking Date'))
+      ->setDescription($this->t('The date this booking is for.'))
       ->setRequired(TRUE)
       ->setDefaultValue([
         'default_date_type' => 'next_hour',
only in patch2:
unchanged:
--- a/src/Entity/BookingContact.php
+++ b/src/Entity/BookingContact.php
@@ -58,8 +58,8 @@ class BookingContact extends ContentEntityBase implements BookingContactInterfac
     $fields = parent::baseFieldDefinitions($entity_type);
 
     $fields['email'] = BaseFieldDefinition::create('email')
-      ->setLabel(t('Email'))
-      ->setDescription(t('The email for this booking'))
+      ->setLabel($this->t('Email'))
+      ->setDescription($this->t('The email for this booking'))
       ->setRequired(TRUE)
       ->setDisplayOptions('form', [
         'type' => 'email_default',
@@ -80,8 +80,8 @@ class BookingContact extends ContentEntityBase implements BookingContactInterfac
       ->setDisplayConfigurable('view', TRUE);
 
     $fields['party_size'] = BaseFieldDefinition::create('integer')
-      ->setLabel(t('Party Size'))
-      ->setDescription(t('The amount of people this booking is for'))
+      ->setLabel($this->t('Party Size'))
+      ->setDescription($this->t('The amount of people this booking is for'))
       ->setRequired(TRUE)
       ->setDefaultValue(1)
       ->addConstraint('CalendarOpeningVacancy')
@@ -105,8 +105,8 @@ class BookingContact extends ContentEntityBase implements BookingContactInterfac
       ->setDisplayConfigurable('view', TRUE);
 
     $fields['booking_instance'] = BaseFieldDefinition::create('entity_reference')
-      ->setLabel(t('Booking Instance'))
-      ->setDescription(t('The Opening Instance this Booking is for.'))
+      ->setLabel($this->t('Booking Instance'))
+      ->setDescription($this->t('The Opening Instance this Booking is for.'))
       ->setRequired(TRUE)
       ->addConstraint('CalendarOpeningIsActive')
       ->addConstraint('CalendarOpeningNotInPast')
@@ -136,8 +136,8 @@ class BookingContact extends ContentEntityBase implements BookingContactInterfac
       ->setDisplayConfigurable('view', TRUE);
 
     $fields['booking'] = BaseFieldDefinition::create('entity_reference')
-      ->setLabel(t('Booking'))
-      ->setDescription(t('Each booking that this contact owns.'))
+      ->setLabel($this->t('Booking'))
+      ->setDescription($this->t('Each booking that this contact owns.'))
       ->setCardinality(FieldStorageDefinitionInterface::CARDINALITY_UNLIMITED)
       ->setSettings([
         'target_type' => 'booking'
@@ -154,8 +154,8 @@ class BookingContact extends ContentEntityBase implements BookingContactInterfac
       ->setDisplayConfigurable('view', TRUE);
 
     $fields['checked_in'] = BaseFieldDefinition::create('boolean')
-      ->setLabel(t('Checked In'))
-      ->setDescription(t('Whether or not this user has showed up to their booked event'))
+      ->setLabel($this->t('Checked In'))
+      ->setDescription($this->t('Whether or not this user has showed up to their booked event'))
       ->setDefaultValue(FALSE)
       ->setSetting('on_label', 'User has checked in')
       ->setDisplayConfigurable('form', FALSE);