Made changes as per Marco's comments

lib/Config/Initializer.php

@@ -33,13 +33,13 @@ class Initializer {
     $subscribers = Env::$db_prefix . 'subscribers';
     $settings = Env::$db_prefix . 'settings';
     $newsletters = Env::$db_prefix . 'newsletters';
-    $lists = Env::$db_prefix . 'lists';
+    $segments = Env::$db_prefix . 'segments';
     $subscriber_segment = Env::$db_prefix . 'subscriber_segment';
 
     define('MP_SUBSCRIBERS_TABLE', $subscribers);
     define('MP_SETTINGS_TABLE', $settings);
     define('MP_NEWSLETTERS_TABLE', $newsletters);
-    define('MP_LISTS_TABLE', $lists);
+    define('MP_SEGMENTS_TABLE', $segments);
     define('MP_SUBSCRIBER_SEGMENT_TABLE', $subscriber_segment);
   }
 

lib/Config/Migrator.php

@@ -13,7 +13,7 @@ class Migrator {
       'subscribers',
       'settings',
       'newsletters',
-      'lists',
+      'segments',
       'subscriber_segment'
     );
   }
@@ -79,7 +79,7 @@ class Migrator {
     return $this->sqlify(__FUNCTION__, $attributes);
   }
 
-  function lists() {
+  function segments() {
     $attributes = array(
         'id mediumint(9) NOT NULL AUTO_INCREMENT,',
         'name varchar(90) NOT NULL,',
@@ -95,7 +95,7 @@ class Migrator {
     $attributes = array(
       'id mediumint(9) NOT NULL AUTO_INCREMENT,',
       'subscriber_id mediumint(9) NOT NULL,',
-      'list_id mediumint(9) NOT NULL,',
+      'segment_id mediumint(9) NOT NULL,',
       'created_at TIMESTAMP NOT NULL DEFAULT 0,',
       'updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,',
       'PRIMARY KEY  (id)'

lib/Models/Segment.php

@@ -4,7 +4,7 @@ namespace MailPoet\Models;
 if(!defined('ABSPATH')) exit;
 
 class Segment extends Model {
-  public static $_table = MP_LISTS_TABLE;
+  public static $_table = MP_SEGMENTS_TABLE;
 
   function __construct() {
     parent::__construct();
@@ -30,6 +30,6 @@ class Segment extends Model {
   }
 
   public function subscribers() {
-    return self::has_many_through(__NAMESPACE__ . '\Subscriber', __NAMESPACE__ . '\SubscriberSegment', 'list_id', 'subscriber_id');
+    return $this->has_many_through(__NAMESPACE__ . '\Subscriber', __NAMESPACE__ . '\SubscriberSegment', 'segment_id', 'subscriber_id');
   }
 }

lib/Models/Subscriber.php

@@ -15,7 +15,7 @@ class Subscriber extends Model {
     ));
   }
 
-  public function lists() {
-    return self::has_many_through(__NAMESPACE__ . '\Segment', __NAMESPACE__ . '\SubscriberSegment', 'subscriber_id', 'list_id');
+  public function segments() {
+    return $this->has_many_through(__NAMESPACE__ . '\Segment', __NAMESPACE__ . '\SubscriberSegment', 'subscriber_id', 'segment_id');
   }
 }

tests/unit/Models/SegmentCest.php

@@ -11,9 +11,9 @@ class SegmentCest {
       'name' => 'some name',
     );
 
-    $this->list = Segment::create();
-    $this->list->hydrate($this->data);
-    $this->saved = $this->list->save();
+    $this->segment = Segment::create();
+    $this->segment->hydrate($this->data);
+    $this->saved = $this->segment->save();
   }
 
   function itCanBeCreated() {
@@ -29,35 +29,35 @@ class SegmentCest {
   }
 
   function itHasACreatedAtOnCreation() {
-    $list = Segment::where('name', $this->data['name'])
+    $segment = Segment::where('name', $this->data['name'])
       ->findOne();
-    $time_difference = strtotime($list->created_at) >= $this->before_time;
+    $time_difference = strtotime($segment->created_at) >= $this->before_time;
     expect($time_difference)->equals(true);
   }
 
   function itHasAnUpdatedAtOnCreation() {
-    $list = Segment::where('name', $this->data['name'])
+    $segment = Segment::where('name', $this->data['name'])
       ->findOne();
-    $time_difference = strtotime($list->updated_at) >= $this->before_time;
+    $time_difference = strtotime($segment->updated_at) >= $this->before_time;
     expect($time_difference)->equals(true);
   }
 
   function itKeepsTheCreatedAtOnUpdate() {
-    $list = Segment::where('name', $this->data['name'])
+    $segment = Segment::where('name', $this->data['name'])
       ->findOne();
-    $old_created_at = $list->created_at;
-    $list->name = 'new name';
-    $list->save();
-    expect($old_created_at)->equals($list->created_at);
+    $old_created_at = $segment->created_at;
+    $segment->name = 'new name';
+    $segment->save();
+    expect($old_created_at)->equals($segment->created_at);
   }
 
   function itUpdatesTheUpdatedAtOnUpdate() {
-    $list = Segment::where('name', $this->data['name'])
+    $segment = Segment::where('name', $this->data['name'])
       ->findOne();
     $update_time = time();
-    $list->name = 'new name';
-    $list->save();
-    $time_difference = strtotime($list->updated_at) >= $update_time;
+    $segment->name = 'new name';
+    $segment->save();
+    $time_difference = strtotime($segment->updated_at) >= $update_time;
     expect($time_difference)->equals(true);
   }
 
@@ -97,12 +97,12 @@ class SegmentCest {
       $subscriber->save();
       $association = SubscriberSegment::create();
       $association->subscriber_id = $subscriber->id;
-      $association->list_id = $this->list->id;
+      $association->segment_id = $this->segment->id;
       $association->save();
     }
 
-    $list = Segment::find_one($this->list->id);
-    $subscribers = $list->subscribers()
+    $segment = Segment::find_one($this->segment->id);
+    $subscribers = $segment->subscribers()
       ->find_array();
     expect(count($subscribers))->equals(2);
   }

tests/unit/Models/SubscriberCest.php

@@ -53,23 +53,23 @@ class SubscriberCest {
     expect($saved)->equals(false);
   }
 
-  function itCanHaveAList() {
-    $listData = array(
+  function itCanHaveASegment() {
+    $segmentData = array(
       'name' => 'some name'
     );
 
-    $list = Segment::create();
-    $list->hydrate($listData);
-    $list->save();
+    $segment = Segment::create();
+    $segment->hydrate($segmentData);
+    $segment->save();
     $association = SubscriberSegment::create();
     $association->subscriber_id = $this->subscriber->id;
-    $association->list_id = $list->id;
+    $association->segment_id = $segment->id;
     $association->save();
 
     $subscriber = Subscriber::find_one($this->subscriber->id);
-    $subscriberList = $subscriber->lists()
+    $subscriberSegment = $subscriber->segments()
       ->find_one();
-    expect($subscriberList->id)->equals($list->id);
+    expect($subscriberSegment->id)->equals($segment->id);
   }
 
   function _after() {