diff --git a/changelog.md b/changelog.md
index a8d5bf7..8cc2646 100644
--- a/changelog.md
+++ b/changelog.md
@@ -2,6 +2,10 @@
 
 All notable changes to this project will be documented in this file.
 
+## [1.2.2] - 2019-07-08
+### Changed
+- fix error in `WrapperDataProcessor`
+
 ## [1.2.1] - 2019-07-08
 ### Changed
 - fix errors in `generate-ide-test-containers`
@@ -40,6 +44,7 @@ All notable changes to this project will be documented in this file.
 - command `generate-ide-test-containers` that generate service file for IDE used to autocomplete
 
 
+[1.2.2]: https://github.com/raptor-mvk/test-utils/compare/v1.2.1...v1.2.2
 [1.2.1]: https://github.com/raptor-mvk/test-utils/compare/v1.2.0...v1.2.1
 [1.2.0]: https://github.com/raptor-mvk/test-utils/compare/v1.1.0...v1.2.0
 [1.1.0]: https://github.com/raptor-mvk/test-utils/compare/v1.0.0...v1.1.0
diff --git a/readme.md b/readme.md
index 3077867..981d079 100644
--- a/readme.md
+++ b/readme.md
@@ -1,4 +1,4 @@
-# Raptor Test Utils v1.2.1
+# Raptor Test Utils v1.2.2
 
 (c) Mikhail Kamorin aka raptor_MVK
 
diff --git a/src/TestUtils/DataProcessor/WrapperDataProcessor.php b/src/TestUtils/DataProcessor/WrapperDataProcessor.php
index 0518e57..c559560 100644
--- a/src/TestUtils/DataProcessor/WrapperDataProcessor.php
+++ b/src/TestUtils/DataProcessor/WrapperDataProcessor.php
@@ -27,6 +27,6 @@ protected function processTestCase(array $element, string $name, ?array $default
         if ($this->hasProcessed($name)) {
             throw new DataParseException("Non-unique test name $name was found.");
         }
-        $this->addProcessed($name, new TestDataContainer(array_merge($default ?? [], $element)));
+        $this->addProcessed($name, [new TestDataContainer(array_merge($default ?? [], $element))]);
     }
 }
diff --git a/tests/TestUtils/DataProcessor/WrapperDataProcessorTests.php b/tests/TestUtils/DataProcessor/WrapperDataProcessorTests.php
index b4fd290..f9d574b 100644
--- a/tests/TestUtils/DataProcessor/WrapperDataProcessorTests.php
+++ b/tests/TestUtils/DataProcessor/WrapperDataProcessorTests.php
@@ -8,6 +8,7 @@
 use Raptor\TestUtils\Exceptions\DataParseException;
 use Raptor\TestUtils\ExtraAssertions;
 use Raptor\TestUtils\TestDataContainer\TestDataContainer;
+use function is_array;
 
 /**
  * @author Mikhail Kamorin aka raptor_MVK
@@ -69,19 +70,24 @@ private function prepareNonUniqueNameTestData(): array
     }
 
     /**
-     * Checks that method _process_ returns array consists of instances of _TestContainer_.
+     * Checks that method _process_ returns array of arrays, each of which contains single TestDataContainer instance.
+     *
+     * @param string $json
      *
      * @dataProvider correctDataProvider
      */
-    public function testProcessReturnsResultWithTestContainersAsElements(): void
+    public function testProcessReturnsArrayOfArraysContainingSingleTestDataContainerInstance(string $json): void
     {
-        $testData = $this->prepareMultiResultTestJson();
         $dataProcessor = new WrapperDataProcessor();
 
-        $actual = $dataProcessor->process($testData);
+        $processed = $dataProcessor->process($json);
 
-        $message = 'All elements of resulting array should be instances of TestContainer';
-        static::assertContainsOnly(TestDataContainer::class, $actual, false, $message);
+        $result = true;
+        foreach ($processed as $value) {
+            $result = $result && is_array($value) && (count($value) === 1) &&
+                ($value[0] instanceof TestDataContainer);
+        }
+        static::assertTrue($result, 'Process should return array of arrays with single element');
     }
 
     /**
@@ -177,8 +183,8 @@ public function testProcessReturnsCorrectResult(string $json, array $expected):
 
         $actual = [];
         foreach ($processed as $key => $value) {
-            /** @var TestDataContainer $value */
-            $actual[$key] = $value->allData();
+            /** @var array $value */
+            $actual[$key] = $value[0]->allData();
         }
         static::assertArraysAreSame($expected, $actual);
     }
diff --git a/tests/TestUtils/WithDataLoaderTests.php b/tests/TestUtils/WithDataLoaderTests.php
index cad92dd..b7c4ed9 100644
--- a/tests/TestUtils/WithDataLoaderTests.php
+++ b/tests/TestUtils/WithDataLoaderTests.php
@@ -33,8 +33,9 @@ public function testLoadReturnsCorrectData(): void
         $content = $this->prepareFileContent();
         $this->addFileToVFS($filename, null, $content);
         $fullFilename = $this->getFullPath($filename);
-        $extractData = static function (TestDataContainer $container) {
-            return $container->allData();
+        $extractData = static function (array $container) {
+            /** @var TestDataContainer[] $container */
+            return $container[0]->allData();
         };
         $expectedData = $this->prepareExpectedResult();