[12.x] Add whereIf() method to Eloquent Builder

src/Illuminate/Database/Eloquent/Builder.php

@@ -334,6 +334,20 @@ public function where($column, $operator = null, $value = null, $boolean = 'and'
         return $this;
     }
 
+    /**
+     * Apply a "where" condition if the given condition is true.
+     *
+     * @param  bool  $condition
+     * @param  string  $column
+     * @param  string  $operator
+     * @param  mixed  $value
+     * @return \Illuminate\Database\Eloquent\Builder
+     */
+    public function whereIf($condition, $column, $operator = '=', $value = null)
+    {
+        return $condition ? $this->where($column, $operator, $value) : $this;
+    }
+
     /**
      * Add a basic where clause to the query, and return the first result.
      *

tests/Database/DatabaseEloquentBuilderTest.php

@@ -2642,6 +2642,38 @@ protected function getMockQueryBuilder()
 
         return $query;
     }
+
+    public function testWhereIfAppliesConditionWhenTrue()
+    {
+        $builder = $this->getMockBuilder(Builder::class)
+            ->disableOriginalConstructor()
+            ->onlyMethods(['where'])
+            ->getMock();
+
+        $builder->expects($this->once())
+            ->method('where')
+            ->with('foo', '=', 'bar')
+            ->willReturnSelf();
+
+        $result = $builder->whereIf(true, 'foo', '=', 'bar');
+
+        $this->assertSame($builder, $result);
+    }
+
+    public function testWhereIfDoesNotApplyConditionWhenFalse()
+    {
+        $builder = $this->getMockBuilder(Builder::class)
+            ->disableOriginalConstructor()
+            ->onlyMethods(['where'])
+            ->getMock();
+
+        $builder->expects($this->never())
+            ->method('where');
+
+        $result = $builder->whereIf(false, 'foo', '=', 'bar');
+
+        $this->assertSame($builder, $result);
+    }
 }
 
 class EloquentBuilderTestStub extends Model