Add support for query builder

src/Illuminate/Database/Query/Builder.php

@@ -4,6 +4,7 @@
 
 use Closure;
 use DateTimeInterface;
+use Exception;
 use Illuminate\Contracts\Support\Arrayable;
 use Illuminate\Database\Concerns\BuildsQueries;
 use Illuminate\Database\Concerns\ExplainsQueries;
@@ -12,6 +13,7 @@
 use Illuminate\Database\Eloquent\Relations\Relation;
 use Illuminate\Database\Query\Grammars\Grammar;
 use Illuminate\Database\Query\Processors\Processor;
+use Illuminate\Pagination\CursorPaginator;
 use Illuminate\Pagination\Paginator;
 use Illuminate\Support\Arr;
 use Illuminate\Support\Collection;
@@ -2360,6 +2362,73 @@ public function simplePaginate($perPage = 15, $columns = ['*'], $pageName = 'pag
         ]);
     }
 
+    /**
+     * Get a paginator only supporting simple next and previous links.
+     *
+     * This is more efficient on larger data-sets, etc.
+     *
+     * @param  int|null  $perPage
+     * @param  array  $columns
+     * @param  string  $cursorName
+     * @param  string|null  $cursor
+     * @return \Illuminate\Contracts\Pagination\Paginator
+     * @throws \Exception
+     */
+    public function cursorPaginate($perPage = 15, $columns = ['*'], $cursorName = 'cursor', $cursor = null)
+    {
+        $cursor = $cursor ?: CursorPaginator::resolveCurrentCursor($cursorName);
+
+        $orders = $this->ensureOrderForCursorPagination(! is_null($cursor) && $cursor->isPrev());
+
+        $orderDirection = $orders->first()['direction'] ?? 'asc';
+
+        $comparisonOperator = ($orderDirection === 'asc' ? '>' : '<');
+
+        $parameters = $orders->pluck('column')->toArray();
+
+        if (count($parameters) === 1 && ! is_null($cursor)) {
+            $this->where($column = $parameters[0], $comparisonOperator, $cursor->getParam($column));
+        } elseif (count($parameters) > 1 && ! is_null($cursor)) {
+            $this->whereRowValues($parameters, $comparisonOperator, $cursor->getParams($parameters));
+        }
+
+        $this->limit($perPage + 1);
+
+        return $this->cursorPaginator($this->get($columns), $perPage, $cursor, [
+            'path' => Paginator::resolveCurrentPath(),
+            'cursorName' => $cursorName,
+            'parameters' => $parameters,
+        ]);
+    }
+
+    /**
+     * Ensure the proper order by required for cursor pagination.
+     *
+     * @param  bool  $shouldReverse
+     * @return \Illuminate\Support\Collection
+     * @throws \Exception
+     */
+    protected function ensureOrderForCursorPagination($shouldReverse = false)
+    {
+        $this->enforceOrderBy();
+
+        $orderDirections = collect($this->orders)->pluck('direction')->unique();
+
+        if ($orderDirections->count() > 1) {
+            throw new Exception('Only a single order by direction is supported in cursor pagination.');
+        }
+
+        if ($shouldReverse) {
+            $this->orders = collect($this->orders)->map(function ($order) {
+                $order['direction'] = ($order['direction'] === 'asc' ? 'desc' : 'asc');
+
+                return $order;
+            })->toArray();
+        }
+
+        return collect($this->orders);
+    }
+
     /**
      * Get the count of the total records for the paginator.
      *

src/Illuminate/Pagination/AbstractCursorPaginator.php

@@ -2,12 +2,14 @@
 
 namespace Illuminate\Pagination;
 
+use ArrayAccess;
 use Closure;
 use Illuminate\Contracts\Support\Htmlable;
 use Illuminate\Support\Arr;
 use Illuminate\Support\Collection;
 use Illuminate\Support\Str;
 use Illuminate\Support\Traits\ForwardsCalls;
+use stdClass;
 
 /**
  * @mixin \Illuminate\Support\Collection
@@ -168,7 +170,9 @@ public function nextCursor()
     }
 
     /**
-     * @param  \ArrayAccess  $item
+     * Get a cursor instance for the given item.
+     *
+     * @param  \ArrayAccess|\stdClass  $item
      * @param  bool  $isNext
      * @return \Illuminate\Pagination\Cursor
      */
@@ -178,14 +182,20 @@ public function getCursorForItem($item, $isNext = true)
     }
 
     /**
-     * @param  \ArrayAccess  $item
+     * @param  \ArrayAccess|\stdClass  $item
      */
     public function getParametersForItem($item)
     {
         return collect($this->parameters)
             ->flip()
             ->map(function ($_, $parameterName) use ($item) {
-                return $item[$parameterName] ?? $item[Str::afterLast($parameterName, '.')];
+                if ($item instanceof ArrayAccess) {
+                    return $item[$parameterName] ?? $item[Str::afterLast($parameterName, '.')];
+                } else if ($item instanceof stdClass) {
+                    return $item->{$parameterName} ?? $item->{Str::afterLast($parameterName, '.')};
+                }
+
+                throw new \Exception('A cursor paginator item must either implement ArrayAccess or be an stdClass instance');
             })->toArray();
     }
 

tests/Integration/Database/EloquentCursorPaginateTest.php

@@ -0,0 +1,99 @@
+<?php
+
+namespace Illuminate\Tests\Integration\Database;
+
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+/**
+ * @group integration
+ */
+class EloquentCursorPaginateTest extends DatabaseTestCase
+{
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        Schema::create('posts', function (Blueprint $table) {
+            $table->increments('id');
+            $table->string('title')->nullable();
+            $table->unsignedInteger('user_id')->nullable();
+            $table->timestamps();
+        });
+
+        Schema::create('users', function ($table) {
+            $table->increments('id');
+            $table->timestamps();
+        });
+    }
+
+    public function testCursorPaginationOnTopOfColumns()
+    {
+        for ($i = 1; $i <= 50; $i++) {
+            Post::create([
+                'title' => 'Title '.$i,
+            ]);
+        }
+
+        $this->assertCount(15, Post::cursorPaginate(15, ['id', 'title']));
+    }
+
+    public function testPaginationWithDistinct()
+    {
+        for ($i = 1; $i <= 3; $i++) {
+            Post::create(['title' => 'Hello world']);
+            Post::create(['title' => 'Goodbye world']);
+        }
+
+        $query = Post::query()->distinct();
+
+        $this->assertEquals(6, $query->get()->count());
+        $this->assertEquals(6, $query->count());
+        $this->assertCount(6, $query->cursorPaginate()->items());
+    }
+
+    public function testPaginationWithDistinctColumnsAndSelect()
+    {
+        for ($i = 1; $i <= 3; $i++) {
+            Post::create(['title' => 'Hello world']);
+            Post::create(['title' => 'Goodbye world']);
+        }
+
+        $query = Post::query()->distinct('title')->select('title');
+
+        $this->assertEquals(2, $query->get()->count());
+        $this->assertEquals(2, $query->count());
+        $this->assertCount(2, $query->cursorPaginate()->items());
+    }
+
+    public function testPaginationWithDistinctColumnsAndSelectAndJoin()
+    {
+        for ($i = 1; $i <= 5; $i++) {
+            $user = User::create();
+            for ($j = 1; $j <= 10; $j++) {
+                Post::create([
+                    'title' => 'Title '.$i,
+                    'user_id' => $user->id,
+                ]);
+            }
+        }
+
+        $query = User::query()->join('posts', 'posts.user_id', '=', 'users.id')
+            ->distinct('users.id')->select('users.*');
+
+        $this->assertEquals(5, $query->get()->count());
+        $this->assertEquals(5, $query->count());
+        $this->assertCount(5, $query->cursorPaginate()->items());
+    }
+}
+
+class Post extends Model
+{
+    protected $guarded = [];
+}
+
+class User extends Model
+{
+    protected $guarded = [];
+}

tests/Integration/Database/EloquentPaginateTest.php

@@ -1,11 +1,10 @@
 <?php
 
-namespace Illuminate\Tests\Integration\Database\EloquentPaginateTest;
+namespace Illuminate\Tests\Integration\Database;
 
 use Illuminate\Database\Eloquent\Model;
 use Illuminate\Database\Schema\Blueprint;
 use Illuminate\Support\Facades\Schema;
-use Illuminate\Tests\Integration\Database\DatabaseTestCase;
 
 /**
  * @group integration