[8.x] Add is() method to 1-1 relations for model comparison

src/Illuminate/Database/Eloquent/Relations/BelongsTo.php

@@ -5,11 +5,12 @@
 use Illuminate\Database\Eloquent\Builder;
 use Illuminate\Database\Eloquent\Collection;
 use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\Concerns\ComparesWithModels;
 use Illuminate\Database\Eloquent\Relations\Concerns\SupportsDefaultModels;
 
 class BelongsTo extends Relation
 {
-    use SupportsDefaultModels;
+    use ComparesWithModels, SupportsDefaultModels;
 
     /**
      * The child model instance of the relation.
@@ -340,6 +341,16 @@ public function getQualifiedForeignKeyName()
         return $this->child->qualifyColumn($this->foreignKey);
     }
 
+    /**
+     * Get the key value of the child's foreign key.
+     *
+     * @return mixed
+     */
+    public function getParentKey()
+    {
+        return $this->child->{$this->foreignKey};
+    }
+
     /**
      * Get the associated key of the relationship.
      *
@@ -360,6 +371,17 @@ public function getQualifiedOwnerKeyName()
         return $this->related->qualifyColumn($this->ownerKey);
     }
 
+    /**
+     * Get the value of the model's associated key.
+     *
+     * @param  \Illuminate\Database\Eloquent\Model  $model
+     * @return mixed
+     */
+    protected function getRelatedKeyFrom(Model $model)
+    {
+        return $model->{$this->ownerKey};
+    }
+
     /**
      * Get the name of the relationship.
      *

src/Illuminate/Database/Eloquent/Relations/Concerns/ComparesWithModels.php

@@ -0,0 +1,68 @@
+<?php
+
+namespace Illuminate\Database\Eloquent\Relations\Concerns;
+
+use Illuminate\Database\Eloquent\Model;
+
+trait ComparesWithModels
+{
+    /**
+     * Determine if the model is the related instance of the relationship.
+     *
+     * @param  \Illuminate\Database\Eloquent\Model|null  $model
+     * @return bool
+     */
+    public function is($model)
+    {
+        return ! is_null($model) &&
+               $this->compareKeys($this->getParentKey(), $this->getRelatedKeyFrom($model)) &&
+               $this->related->getTable() === $model->getTable() &&
+               $this->related->getConnectionName() === $model->getConnectionName();
+    }
+
+    /**
+     * Determine if the model is not the related instance of the relationship.
+     *
+     * @param  \Illuminate\Database\Eloquent\Model|null  $model
+     * @return bool
+     */
+    public function isNot($model)
+    {
+        return ! $this->is($model);
+    }
+
+    /**
+     * Get the value of the parent model's key.
+     *
+     * @return mixed
+     */
+    abstract public function getParentKey();
+
+    /**
+     * Get the value of the model's related key.
+     *
+     * @param  \Illuminate\Database\Eloquent\Model  $model
+     * @return mixed
+     */
+    abstract protected function getRelatedKeyFrom(Model $model);
+
+    /**
+     * Compare the parent key with the related key.
+     *
+     * @param  mixed  $parentKey
+     * @param  mixed  $relatedKey
+     * @return bool
+     */
+    protected function compareKeys($parentKey, $relatedKey)
+    {
+        if (empty($parentKey) || empty($relatedKey)) {
+            return false;
+        }
+
+        if (is_int($parentKey) || is_int($relatedKey)) {
+            return (int) $parentKey === (int) $relatedKey;
+        }
+
+        return $parentKey === $relatedKey;
+    }
+}

src/Illuminate/Database/Eloquent/Relations/HasOne.php

@@ -4,11 +4,12 @@
 
 use Illuminate\Database\Eloquent\Collection;
 use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\Concerns\ComparesWithModels;
 use Illuminate\Database\Eloquent\Relations\Concerns\SupportsDefaultModels;
 
 class HasOne extends HasOneOrMany
 {
-    use SupportsDefaultModels;
+    use ComparesWithModels, SupportsDefaultModels;
 
     /**
      * Get the results of the relationship.
@@ -65,4 +66,15 @@ public function newRelatedInstanceFor(Model $parent)
             $this->getForeignKeyName(), $parent->{$this->localKey}
         );
     }
+
+    /**
+     * Get the value of the model's foreign key.
+     *
+     * @param  \Illuminate\Database\Eloquent\Model  $model
+     * @return mixed
+     */
+    protected function getRelatedKeyFrom(Model $model)
+    {
+        return $model->getAttribute($this->getForeignKeyName());
+    }
 }

src/Illuminate/Database/Eloquent/Relations/MorphOne.php

@@ -4,11 +4,12 @@
 
 use Illuminate\Database\Eloquent\Collection;
 use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\Concerns\ComparesWithModels;
 use Illuminate\Database\Eloquent\Relations\Concerns\SupportsDefaultModels;
 
 class MorphOne extends MorphOneOrMany
 {
-    use SupportsDefaultModels;
+    use ComparesWithModels, SupportsDefaultModels;
 
     /**
      * Get the results of the relationship.
@@ -65,4 +66,15 @@ public function newRelatedInstanceFor(Model $parent)
                     ->setAttribute($this->getForeignKeyName(), $parent->{$this->localKey})
                     ->setAttribute($this->getMorphType(), $this->morphClass);
     }
+
+    /**
+     * Get the value of the model's foreign key.
+     *
+     * @param  \Illuminate\Database\Eloquent\Model  $model
+     * @return mixed
+     */
+    protected function getRelatedKeyFrom(Model $model)
+    {
+        return $model->getAttribute($this->getForeignKeyName());
+    }
 }

tests/Database/DatabaseEloquentBelongsToTest.php

@@ -181,6 +181,169 @@ public function testDefaultEagerConstraintsWhenNotIncrementing()
         $relation->addEagerConstraints($models);
     }
 
+    public function testIsNotNull()
+    {
+        $relation = $this->getRelation();
+
+        $this->related->shouldReceive('getConnectionName')->never();
+
+        $this->assertFalse($relation->is(null));
+    }
+
+    public function testIsModel()
+    {
+        $relation = $this->getRelation();
+
+        $this->related->shouldReceive('getConnectionName')->once()->andReturn('relation');
+
+        $model = m::mock(Model::class);
+        $model->shouldReceive('getAttribute')->once()->with('id')->andReturn('foreign.value');
+        $model->shouldReceive('getTable')->once()->andReturn('relation');
+        $model->shouldReceive('getConnectionName')->once()->andReturn('relation');
+
+        $this->assertTrue($relation->is($model));
+    }
+
+    public function testIsModelWithIntegerParentKey()
+    {
+        $parent = m::mock(Model::class);
+
+        // when addConstraints is called we need to return the foreign value
+        $parent->shouldReceive('getAttribute')->once()->with('foreign_key')->andReturn('foreign.value');
+        // when getParentKey is called we want to return an integer
+        $parent->shouldReceive('getAttribute')->once()->with('foreign_key')->andReturn(1);
+
+        $relation = $this->getRelation($parent);
+
+        $this->related->shouldReceive('getConnectionName')->once()->andReturn('relation');
+
+        $model = m::mock(Model::class);
+        $model->shouldReceive('getAttribute')->once()->with('id')->andReturn('1');
+        $model->shouldReceive('getTable')->once()->andReturn('relation');
+        $model->shouldReceive('getConnectionName')->once()->andReturn('relation');
+
+        $this->assertTrue($relation->is($model));
+    }
+
+    public function testIsModelWithIntegerRelatedKey()
+    {
+        $parent = m::mock(Model::class);
+
+        // when addConstraints is called we need to return the foreign value
+        $parent->shouldReceive('getAttribute')->once()->with('foreign_key')->andReturn('foreign.value');
+        // when getParentKey is called we want to return a string
+        $parent->shouldReceive('getAttribute')->once()->with('foreign_key')->andReturn('1');
+
+        $relation = $this->getRelation($parent);
+
+        $this->related->shouldReceive('getConnectionName')->once()->andReturn('relation');
+
+        $model = m::mock(Model::class);
+        $model->shouldReceive('getAttribute')->once()->with('id')->andReturn(1);
+        $model->shouldReceive('getTable')->once()->andReturn('relation');
+        $model->shouldReceive('getConnectionName')->once()->andReturn('relation');
+
+        $this->assertTrue($relation->is($model));
+    }
+
+    public function testIsModelWithIntegerKeys()
+    {
+        $parent = m::mock(Model::class);
+
+        // when addConstraints is called we need to return the foreign value
+        $parent->shouldReceive('getAttribute')->once()->with('foreign_key')->andReturn('foreign.value');
+        // when getParentKey is called we want to return an integer
+        $parent->shouldReceive('getAttribute')->once()->with('foreign_key')->andReturn(1);
+
+        $relation = $this->getRelation($parent);
+
+        $this->related->shouldReceive('getConnectionName')->once()->andReturn('relation');
+
+        $model = m::mock(Model::class);
+        $model->shouldReceive('getAttribute')->once()->with('id')->andReturn(1);
+        $model->shouldReceive('getTable')->once()->andReturn('relation');
+        $model->shouldReceive('getConnectionName')->once()->andReturn('relation');
+
+        $this->assertTrue($relation->is($model));
+    }
+
+    public function testIsNotModelWithNullParentKey()
+    {
+        $parent = m::mock(Model::class);
+
+        // when addConstraints is called we need to return the foreign value
+        $parent->shouldReceive('getAttribute')->once()->with('foreign_key')->andReturn('foreign.value');
+        // when getParentKey is called we want to return null
+        $parent->shouldReceive('getAttribute')->once()->with('foreign_key')->andReturn(null);
+
+        $relation = $this->getRelation($parent);
+
+        $this->related->shouldReceive('getConnectionName')->never();
+
+        $model = m::mock(Model::class);
+        $model->shouldReceive('getAttribute')->once()->with('id')->andReturn('foreign.value');
+        $model->shouldReceive('getTable')->never();
+        $model->shouldReceive('getConnectionName')->never();
+
+        $this->assertFalse($relation->is($model));
+    }
+
+    public function testIsNotModelWithNullRelatedKey()
+    {
+        $relation = $this->getRelation();
+
+        $this->related->shouldReceive('getConnectionName')->never();
+
+        $model = m::mock(Model::class);
+        $model->shouldReceive('getAttribute')->once()->with('id')->andReturn(null);
+        $model->shouldReceive('getTable')->never();
+        $model->shouldReceive('getConnectionName')->never();
+
+        $this->assertFalse($relation->is($model));
+    }
+
+    public function testIsNotModelWithAnotherKey()
+    {
+        $relation = $this->getRelation();
+
+        $this->related->shouldReceive('getConnectionName')->never();
+
+        $model = m::mock(Model::class);
+        $model->shouldReceive('getAttribute')->once()->with('id')->andReturn('foreign.value.two');
+        $model->shouldReceive('getTable')->never();
+        $model->shouldReceive('getConnectionName')->never();
+
+        $this->assertFalse($relation->is($model));
+    }
+
+    public function testIsNotModelWithAnotherTable()
+    {
+        $relation = $this->getRelation();
+
+        $this->related->shouldReceive('getConnectionName')->never();
+
+        $model = m::mock(Model::class);
+        $model->shouldReceive('getAttribute')->once()->with('id')->andReturn('foreign.value');
+        $model->shouldReceive('getTable')->once()->andReturn('table.two');
+        $model->shouldReceive('getConnectionName')->never();
+
+        $this->assertFalse($relation->is($model));
+    }
+
+    public function testIsNotModelWithAnotherConnection()
+    {
+        $relation = $this->getRelation();
+
+        $this->related->shouldReceive('getConnectionName')->once()->andReturn('relation');
+
+        $model = m::mock(Model::class);
+        $model->shouldReceive('getAttribute')->once()->with('id')->andReturn('foreign.value');
+        $model->shouldReceive('getTable')->once()->andReturn('relation');
+        $model->shouldReceive('getConnectionName')->once()->andReturn('relation.two');
+
+        $this->assertFalse($relation->is($model));
+    }
+
     protected function getRelation($parent = null, $keyType = 'int')
     {
         $this->builder = m::mock(Builder::class);