From 90892f99452693d3c76562359cbc683544ea00c8 Mon Sep 17 00:00:00 2001
From: Graham Campbell <GrahamCampbell@users.noreply.github.com>
Date: Tue, 30 Jun 2020 14:23:27 +0100
Subject: [PATCH] Correct implementation of float casting comparison (#33322)

---
 .../Database/Eloquent/Concerns/HasAttributes.php   |  2 ++
 tests/Database/DatabaseEloquentModelTest.php       | 14 ++++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/src/Illuminate/Database/Eloquent/Concerns/HasAttributes.php b/src/Illuminate/Database/Eloquent/Concerns/HasAttributes.php
index 986e8a72121f..b6c080a7f2e5 100644
--- a/src/Illuminate/Database/Eloquent/Concerns/HasAttributes.php
+++ b/src/Illuminate/Database/Eloquent/Concerns/HasAttributes.php
@@ -1178,6 +1178,8 @@ public function originalIsEquivalent($key, $current)
         } elseif ($this->hasCast($key, ['object', 'collection'])) {
             return $this->castAttribute($key, $current) ==
                 $this->castAttribute($key, $original);
+        } elseif ($this->hasCast($key, ['real', 'float', 'double'])) {
+            return abs($this->castAttribute($key, $current) - $this->castAttribute($key, $original)) < PHP_FLOAT_EPSILON * 4;
         } elseif ($this->hasCast($key)) {
             return $this->castAttribute($key, $current) ===
                    $this->castAttribute($key, $original);
diff --git a/tests/Database/DatabaseEloquentModelTest.php b/tests/Database/DatabaseEloquentModelTest.php
index b5c0bc8689f2..e918aa2ec35b 100755
--- a/tests/Database/DatabaseEloquentModelTest.php
+++ b/tests/Database/DatabaseEloquentModelTest.php
@@ -148,6 +148,19 @@ public function testCleanAttributes()
         $this->assertFalse($model->isClean(['foo', 'bar']));
     }
 
+    public function testCleanWhenFloatUpdateAttribute()
+    {
+        // test is equivalent
+        $model = new EloquentModelStub(['castedFloat' => 8 - 6.4]);
+        $model->syncOriginal();
+        $this->assertTrue($model->originalIsEquivalent('castedFloat', 1.6));
+
+        // test is not equivalent
+        $model = new EloquentModelStub(['castedFloat' => 5.6]);
+        $model->syncOriginal();
+        $this->assertFalse($model->originalIsEquivalent('castedFloat', 5.5));
+    }
+
     public function testCalculatedAttributes()
     {
         $model = new EloquentModelStub;
@@ -1992,6 +2005,7 @@ class EloquentModelStub extends Model
     protected $table = 'stub';
     protected $guarded = [];
     protected $morph_to_stub_type = EloquentModelSaveStub::class;
+    protected $casts = ['castedFloat' => 'float'];
 
     public function getListItemsAttribute($value)
     {