[5.2] Cast incrementing IDs to Integer by default

src/Illuminate/Database/Eloquent/Model.php

@@ -2513,7 +2513,7 @@ public function attributesToArray()
         // Next we will handle any casts that have been setup for this model and cast
         // the values to their appropriate type. If the attribute has a mutator we
         // will not perform the cast on those attributes to avoid any confusion.
-        foreach ($this->casts as $key => $value) {
+        foreach ($this->getCasts() as $key => $value) {
             if (! array_key_exists($key, $attributes) ||
                 in_array($key, $mutatedAttributes)) {
                 continue;
@@ -2785,7 +2785,23 @@ protected function mutateAttributeForArray($key, $value)
      */
     protected function hasCast($key)
     {
-        return array_key_exists($key, $this->casts);
+        return array_key_exists($key, $this->getCasts());
+    }
+
+    /**
+     * Get the casts array.
+     *
+     * @return array
+     */
+    protected function getCasts()
+    {
+        if ($this->incrementing) {
+            return array_merge([
+                $this->getKeyName() => 'int',
+            ], $this->casts);
+        }
+
+        return $this->casts;
     }
 
     /**
@@ -2820,7 +2836,7 @@ protected function isJsonCastable($key)
      */
     protected function getCastType($key)
     {
-        return trim(strtolower($this->casts[$key]));
+        return trim(strtolower($this->getCasts()[$key]));
     }
 
     /**

tests/Database/DatabaseEloquentIntegrationTest.php

@@ -582,6 +582,22 @@ public function testToArrayIncludesCustomFormattedTimestamps()
         $this->assertEquals('05-12-12', $array['updated_at']);
     }
 
+    public function testIncrementingPrimaryKeysAreCastToIntegersByDefault()
+    {
+        EloquentTestUser::create(['email' => 'taylorotwell@gmail.com']);
+
+        $user = EloquentTestUser::first();
+        $this->assertInternalType('int', $user->id);
+    }
+
+    public function testDefaultIncrementingPrimaryKeyIntegerCastCanBeOverwritten()
+    {
+        EloquentTestUserWithStringCastId::create(['email' => 'taylorotwell@gmail.com']);
+
+        $user = EloquentTestUserWithStringCastId::first();
+        $this->assertInternalType('string', $user->id);
+    }
+
     /**
      * Helpers...
      */
@@ -672,3 +688,10 @@ public function imageable()
         return $this->morphTo();
     }
 }
+
+class EloquentTestUserWithStringCastId extends EloquentTestUser
+{
+    protected $casts = [
+        'id' => 'string',
+    ];
+}

tests/Database/DatabaseEloquentModelTest.php

@@ -930,7 +930,7 @@ public function testTheMutatorCacheIsPopulated()
 
     public function testRouteKeyIsPrimaryKey()
     {
-        $model = new EloquentModelStub;
+        $model = new EloquentModelNonIncrementingStub;
         $model->id = 'foo';
         $this->assertEquals('foo', $model->getRouteKey());
     }
@@ -1553,3 +1553,10 @@ public function getVisible()
         return ['name', 'id'];
     }
 }
+
+class EloquentModelNonIncrementingStub extends Illuminate\Database\Eloquent\Model
+{
+    protected $table = 'stub';
+    protected $guarded = [];
+    public $incrementing = false;
+}