diff --git a/.github/wait_for_es.php b/.github/wait_for_es.php
new file mode 100644
index 00000000..10501a6e
--- /dev/null
+++ b/.github/wait_for_es.php
@@ -0,0 +1,26 @@
+<?php
+
+use Elasticsearch\ClientBuilder;
+use Elasticsearch\Common\Exceptions\NoNodesAvailableException;
+
+require dirname(__DIR__) . '/vendor/autoload.php';
+
+$retries = 0;
+$maxRetries = 10;
+
+while (true) {
+    try {
+        $client = ClientBuilder::create()->build();
+        $client->ping();
+        echo 'Is up and running' . PHP_EOL;
+        exit(0);
+    } catch (NoNodesAvailableException $e) {
+        if ($retries === $maxRetries) {
+            echo 'Cannot reach elasticsearch server' . PHP_EOL;
+            exit(1);
+        }
+
+        sleep(5);
+        $retries++;
+    }
+}
diff --git a/.github/workflows/phpunit.yml b/.github/workflows/phpunit.yml
new file mode 100644
index 00000000..c8b58315
--- /dev/null
+++ b/.github/workflows/phpunit.yml
@@ -0,0 +1,48 @@
+name: PHPUnit
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    services:
+      elasticsearch:
+        image: elastic/elasticsearch:7.4.0
+        ports:
+          - 9200:9200
+        env:
+          discovery.type: single-node
+    strategy:
+      matrix:
+        php: ['7.4', '8.0']
+    steps:
+    - uses: actions/checkout@v2
+  
+    - name: Setup PHP
+      uses: shivammathur/setup-php@v2
+      with:
+        php-version: ${{ matrix.php }}
+        tools: composer:v2
+        coverage: xdebug
+
+    - name: Validate composer.json and composer.lock
+      run: composer validate
+
+    - name: Install dependencies
+      run: composer install --prefer-dist --no-progress
+
+    - name: Wait for Elasticsearch
+      run: php ./.github/wait_for_es.php
+
+    - name: Run PHPUnit
+      run: vendor/bin/phpunit --coverage-clover=coverage.xml
+
+    - name: Run PHPCS
+      run: vendor/bin/phpcs -p --standard=PSR2 --ignore=vendor/ ./
+    
+    - name: Upload Codecov
+      uses: codecov/codecov-action@v1
+      with:
+        file: ./coverage.xml
diff --git a/.travis.yml b/.travis.yml
deleted file mode 100644
index 65d6b9db..00000000
--- a/.travis.yml
+++ /dev/null
@@ -1,26 +0,0 @@
-sudo: false
-language: php
-php:
-  - 7.1
-  - 7.2
-  - 7.3
-  - 7.4snapshot
-matrix:
-  allow_failures:
-      - php: 7.4snapshot
-env:
-  global:
-    - ES_VERSION=7.4.0 ES_DOWNLOAD_URL=https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-${ES_VERSION}-linux-x86_64.tar.gz
-install:
-  - wget ${ES_DOWNLOAD_URL}
-  - tar -xzf elasticsearch-${ES_VERSION}-linux-x86_64.tar.gz
-  - ./elasticsearch-${ES_VERSION}/bin/elasticsearch -d
-before_script:
-  - if [ "$GITHUB_COMPOSER_AUTH" ]; then composer config -g github-oauth.github.com $GITHUB_COMPOSER_AUTH; fi
-  - composer install --no-interaction --prefer-dist
-script:
-  - wget -q --waitretry=1 --retry-connrefused -T 10 -O - http://127.0.0.1:9200
-  - vendor/bin/phpunit --coverage-clover=coverage.xml
-  - vendor/bin/phpcs -p --standard=PSR2 --ignore=vendor/ ./
-after_script:
-  - travis_retry bash <(curl -s https://codecov.io/bash)
diff --git a/composer.json b/composer.json
index 1cc93d8a..2b633cab 100644
--- a/composer.json
+++ b/composer.json
@@ -11,18 +11,14 @@
         }
     ],
     "require": {
-        "php": "^7.0",
-        "symfony/serializer": "^3.0|^4.0",
-        "paragonie/random_compat": "*"
+        "php": "^7.4 || ^8.0",
+        "symfony/serializer": "^7.0",
+        "elasticsearch/elasticsearch": "^7.0"
     },
     "require-dev": {
-        "elasticsearch/elasticsearch": "^7.0",
-        "phpunit/phpunit": "~6.0",
+        "phpunit/phpunit": "^9.0",
         "squizlabs/php_codesniffer": "^3.0"
     },
-    "suggest": {
-      "elasticsearch/elasticsearch": "This library is for elasticsearch/elasticsearch client to enhance it with DSL functionality."
-    },
     "autoload": {
         "psr-4": {
             "ONGR\\ElasticsearchDSL\\": "src/"
@@ -33,10 +29,9 @@
             "ONGR\\ElasticsearchDSL\\Tests\\": "tests/"
         }
     },
-    "minimum-stability": "dev",
     "extra": {
         "branch-alias": {
-            "dev-master": "7.0-dev"
+            "dev-master": "7.2-dev"
         }
     }
 }
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index 17185e94..7233b3df 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -1,5 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <phpunit
+        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+        xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/9.3/phpunit.xsd"
         backupGlobals="false"
         backupStaticAttributes="false"
         colors="true"
@@ -8,7 +10,6 @@
         convertWarningsToExceptions="true"
         processIsolation="false"
         stopOnFailure="false"
-        syntaxCheck="false"
         bootstrap="vendor/autoload.php">
 
     <testsuites>
@@ -23,16 +24,16 @@
         </testsuite>
     </testsuites>
 
-    <filter>
-        <whitelist>
+    <coverage>
+        <include>
             <directory>./</directory>
-            <exclude>
-                <directory>./tests</directory>
-                <directory>./vendor</directory>
-            </exclude>
-        </whitelist>
-    </filter>
-    <logging>
-        <log type="coverage-text" target="php://stdout" showOnlySummary="true"/>
-    </logging>
+        </include>
+        <exclude>
+            <directory>./tests</directory>
+            <directory>./vendor</directory>
+        </exclude>
+        <report>
+            <text outputFile="php://stdout" showOnlySummary="true"/>
+        </report>
+    </coverage>
 </phpunit>
diff --git a/src/Aggregation/Matrix/MatrixStatsAggregation.php b/src/Aggregation/Matrix/MaxAggregation.php
similarity index 100%
rename from src/Aggregation/Matrix/MatrixStatsAggregation.php
rename to src/Aggregation/Matrix/MaxAggregation.php
diff --git a/src/ParametersTrait.php b/src/ParametersTrait.php
index 013b4b6d..e74927b3 100644
--- a/src/ParametersTrait.php
+++ b/src/ParametersTrait.php
@@ -37,12 +37,15 @@ public function hasParameter($name)
      * Removes parameter.
      *
      * @param string $name
+     * @return $this
      */
     public function removeParameter($name)
     {
         if ($this->hasParameter($name)) {
             unset($this->parameters[$name]);
         }
+
+        return $this;
     }
 
     /**
@@ -70,10 +73,13 @@ public function getParameters()
     /**
      * @param string                 $name
      * @param array|string|int|float|bool|\stdClass $value
+     * @return $this
      */
     public function addParameter($name, $value)
     {
         $this->parameters[$name] = $value;
+
+        return $this;
     }
 
     /**
diff --git a/src/Query/Compound/FunctionScoreQuery.php b/src/Query/Compound/FunctionScoreQuery.php
index e7d96c1b..844bab13 100644
--- a/src/Query/Compound/FunctionScoreQuery.php
+++ b/src/Query/Compound/FunctionScoreQuery.php
@@ -181,7 +181,7 @@ public function addRandomFunction($seed = null, BuilderInterface $query = null)
     /**
      * Adds script score function.
      *
-     * @param string           $inline
+     * @param string           $source
      * @param array            $params
      * @param array            $options
      * @param BuilderInterface $query
@@ -189,7 +189,7 @@ public function addRandomFunction($seed = null, BuilderInterface $query = null)
      * @return $this
      */
     public function addScriptScoreFunction(
-        $inline,
+        $source,
         array $params = [],
         array $options = [],
         BuilderInterface $query = null
@@ -201,7 +201,7 @@ public function addScriptScoreFunction(
                         array_merge(
                             [
                                 'lang' => 'painless',
-                                'inline' => $inline,
+                                'source' => $source,
                                 'params' => $params
                             ],
                             $options
diff --git a/src/SearchEndpoint/AggregationsEndpoint.php b/src/SearchEndpoint/AggregationsEndpoint.php
index 079a6a5d..3e035f43 100644
--- a/src/SearchEndpoint/AggregationsEndpoint.php
+++ b/src/SearchEndpoint/AggregationsEndpoint.php
@@ -27,7 +27,7 @@ class AggregationsEndpoint extends AbstractSearchEndpoint
     /**
      * {@inheritdoc}
      */
-    public function normalize(NormalizerInterface $normalizer, $format = null, array $context = [])
+    public function normalize(NormalizerInterface $normalizer, string $format = null, array $context = [])
     {
         $output = [];
         if (count($this->getAll()) > 0) {
diff --git a/src/SearchEndpoint/HighlightEndpoint.php b/src/SearchEndpoint/HighlightEndpoint.php
index f2b8d8e9..aa57b3d7 100644
--- a/src/SearchEndpoint/HighlightEndpoint.php
+++ b/src/SearchEndpoint/HighlightEndpoint.php
@@ -37,7 +37,7 @@ class HighlightEndpoint extends AbstractSearchEndpoint
     /**
      * {@inheritdoc}
      */
-    public function normalize(NormalizerInterface $normalizer, $format = null, array $context = [])
+    public function normalize(NormalizerInterface $normalizer, string $format = null, array $context = [])
     {
         if ($this->highlight) {
             return $this->highlight->toArray();
diff --git a/src/SearchEndpoint/InnerHitsEndpoint.php b/src/SearchEndpoint/InnerHitsEndpoint.php
index f1562fe6..8428bd88 100644
--- a/src/SearchEndpoint/InnerHitsEndpoint.php
+++ b/src/SearchEndpoint/InnerHitsEndpoint.php
@@ -27,7 +27,7 @@ class InnerHitsEndpoint extends AbstractSearchEndpoint
     /**
      * {@inheritdoc}
      */
-    public function normalize(NormalizerInterface $normalizer, $format = null, array $context = [])
+    public function normalize(NormalizerInterface $normalizer, string $format = null, array $context = [])
     {
         $output = [];
         if (count($this->getAll()) > 0) {
diff --git a/src/SearchEndpoint/PostFilterEndpoint.php b/src/SearchEndpoint/PostFilterEndpoint.php
index 6055b7ed..de3e263c 100644
--- a/src/SearchEndpoint/PostFilterEndpoint.php
+++ b/src/SearchEndpoint/PostFilterEndpoint.php
@@ -26,7 +26,7 @@ class PostFilterEndpoint extends QueryEndpoint
     /**
      * {@inheritdoc}
      */
-    public function normalize(NormalizerInterface $normalizer, $format = null, array $context = [])
+    public function normalize(NormalizerInterface $normalizer, string $format = null, array $context = [])
     {
         if (!$this->getBool()) {
             return null;
diff --git a/src/SearchEndpoint/QueryEndpoint.php b/src/SearchEndpoint/QueryEndpoint.php
index 6212b05d..b7626910 100644
--- a/src/SearchEndpoint/QueryEndpoint.php
+++ b/src/SearchEndpoint/QueryEndpoint.php
@@ -39,7 +39,7 @@ class QueryEndpoint extends AbstractSearchEndpoint implements OrderedNormalizerI
     /**
      * {@inheritdoc}
      */
-    public function normalize(NormalizerInterface $normalizer, $format = null, array $context = [])
+    public function normalize(NormalizerInterface $normalizer, string $format = null, array $context = [])
     {
         if (!$this->filtersSet && $this->hasReference('filter_query')) {
             /** @var BuilderInterface $filter */
diff --git a/src/SearchEndpoint/SortEndpoint.php b/src/SearchEndpoint/SortEndpoint.php
index 2461c858..cd00bb2f 100644
--- a/src/SearchEndpoint/SortEndpoint.php
+++ b/src/SearchEndpoint/SortEndpoint.php
@@ -26,7 +26,7 @@ class SortEndpoint extends AbstractSearchEndpoint
     /**
      * {@inheritdoc}
      */
-    public function normalize(NormalizerInterface $normalizer, $format = null, array $context = [])
+    public function normalize(NormalizerInterface $normalizer, string $format = null, array $context = [])
     {
         $output = [];
 
diff --git a/src/SearchEndpoint/SuggestEndpoint.php b/src/SearchEndpoint/SuggestEndpoint.php
index 2e2e16ac..6d292239 100644
--- a/src/SearchEndpoint/SuggestEndpoint.php
+++ b/src/SearchEndpoint/SuggestEndpoint.php
@@ -27,7 +27,7 @@ class SuggestEndpoint extends AbstractSearchEndpoint
     /**
      * {@inheritdoc}
      */
-    public function normalize(NormalizerInterface $normalizer, $format = null, array $context = [])
+    public function normalize(NormalizerInterface $normalizer, string $format = null, array $context = [])
     {
         $output = [];
         if (count($this->getAll()) > 0) {
diff --git a/src/Serializer/Normalizer/CustomReferencedNormalizer.php b/src/Serializer/Normalizer/CustomReferencedNormalizer.php
index 6cd24a8e..fd32a89b 100644
--- a/src/Serializer/Normalizer/CustomReferencedNormalizer.php
+++ b/src/Serializer/Normalizer/CustomReferencedNormalizer.php
@@ -26,7 +26,7 @@ class CustomReferencedNormalizer extends CustomNormalizer
     /**
      * {@inheritdoc}
      */
-    public function normalize($object, $format = null, array $context = [])
+    public function normalize($object, string $format = null, array $context = [])
     {
         $object->setReferences($this->references);
         $data = parent::normalize($object, $format, $context);
diff --git a/src/Serializer/OrderedSerializer.php b/src/Serializer/OrderedSerializer.php
index bcbb9c3d..9019e43e 100644
--- a/src/Serializer/OrderedSerializer.php
+++ b/src/Serializer/OrderedSerializer.php
@@ -59,7 +59,7 @@ private function order(array $data)
             uasort(
                 $filteredData,
                 function (OrderedNormalizerInterface $a, OrderedNormalizerInterface $b) {
-                    return $a->getOrder() > $b->getOrder();
+                    return $a->getOrder() <=> $b->getOrder();
                 }
             );
 
diff --git a/tests/Functional/AbstractElasticsearchTestCase.php b/tests/Functional/AbstractElasticsearchTestCase.php
index 3c023410..4765f7c6 100644
--- a/tests/Functional/AbstractElasticsearchTestCase.php
+++ b/tests/Functional/AbstractElasticsearchTestCase.php
@@ -31,7 +31,7 @@ abstract class AbstractElasticsearchTestCase extends TestCase
     /**
      * {@inheritdoc}
      */
-    protected function setUp()
+    protected function setUp(): void
     {
         parent::setUp();
 
@@ -109,7 +109,7 @@ protected function getDataArray()
     /**
      * {@inheritdoc}
      */
-    protected function tearDown()
+    protected function tearDown(): void
     {
         parent::tearDown();
         $this->deleteIndex();
diff --git a/tests/Unit/Aggregation/Bucketing/AdjacencyMatrixAggregationTest.php b/tests/Unit/Aggregation/Bucketing/AdjacencyMatrixAggregationTest.php
index f73cc612..038da8c7 100644
--- a/tests/Unit/Aggregation/Bucketing/AdjacencyMatrixAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/AdjacencyMatrixAggregationTest.php
@@ -9,28 +9,27 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\AdjacencyMatrixAggregation;
-use ONGR\ElasticsearchDSL\BuilderInterface;
+use ONGR\ElasticsearchDSL\Aggregation\Bucketing\FiltersAggregation;
 
 /**
  * Unit test for adjacency matrix aggregation.
  */
 class AdjacencyMatrixAggregationTest extends \PHPUnit\Framework\TestCase
 {
-//    /**
-//     * Test if exception is thrown when not anonymous filter is without name.
-//     *
-//     * @expectedException \LogicException
-//     * @expectedExceptionMessage In not anonymous filters filter name must be set.
-//     */
-//    public function testIfExceptionIsThrown()
-//    {
-//        $mock = $this->getMockBuilder('ONGR\ElasticsearchDSL\BuilderInterface')->getMock();
-//        $aggregation = new FiltersAggregation('test_agg');
-//        $aggregation->addFilter($mock);
-//    }
+    /**
+     * Test if exception is thrown when not anonymous filter is without name.
+     */
+    public function testIfExceptionIsThrown()
+    {
+        $this->expectException(\LogicException::class);
+        $this->expectExceptionMessage("In not anonymous filters filter name must be set.");
+        $mock = $this->getMockBuilder('ONGR\ElasticsearchDSL\BuilderInterface')->getMock();
+        $aggregation = new FiltersAggregation('test_agg');
+        $aggregation->addFilter($mock);
+    }
 
     /**
      * Test GetArray method.
@@ -61,7 +60,7 @@ public function testToArray()
     {
         $aggregation = new AdjacencyMatrixAggregation('test_agg');
         $filter = $this->getMockBuilder('ONGR\ElasticsearchDSL\BuilderInterface')
-            ->setMethods(['toArray', 'getType'])
+            ->onlyMethods(['toArray', 'getType'])
             ->getMockForAbstractClass();
         $filter->expects($this->any())
             ->method('toArray')
@@ -95,9 +94,7 @@ public function testToArray()
      */
     public function testFilterConstructor()
     {
-        /** @var BuilderInterface|\PHPUnit_Framework_MockObject_MockObject $builderInterface1 */
         $builderInterface1 = $this->getMockForAbstractClass('ONGR\ElasticsearchDSL\BuilderInterface');
-        /** @var BuilderInterface|\PHPUnit_Framework_MockObject_MockObject $builderInterface2 */
         $builderInterface2 = $this->getMockForAbstractClass('ONGR\ElasticsearchDSL\BuilderInterface');
 
         $aggregation = new AdjacencyMatrixAggregation(
diff --git a/tests/Unit/Aggregation/Bucketing/AudoDateHistogramAggregationTest.php b/tests/Unit/Aggregation/Bucketing/AudoDateHistogramAggregationTest.php
index bece77d3..3a6c21c9 100644
--- a/tests/Unit/Aggregation/Bucketing/AudoDateHistogramAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/AudoDateHistogramAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\AutoDateHistogramAggregation;
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\TermsAggregation;
diff --git a/tests/Unit/Aggregation/Bucketing/ChildrenAggregationTest.php b/tests/Unit/Aggregation/Bucketing/ChildrenAggregationTest.php
index f4cb6b3a..8e10461a 100644
--- a/tests/Unit/Aggregation/Bucketing/ChildrenAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/ChildrenAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\ChildrenAggregation;
 
@@ -20,11 +20,10 @@ class ChildrenAggregationTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Tests if ChildrenAggregation#getArray throws exception when expected.
-     *
-     * @expectedException \LogicException
      */
     public function testGetArrayException()
     {
+        $this->expectException(\LogicException::class);
         $aggregation = new ChildrenAggregation('foo');
         $aggregation->getArray();
     }
diff --git a/tests/Unit/Aggregation/Bucketing/CompositeAggregationTest.php b/tests/Unit/Aggregation/Bucketing/CompositeAggregationTest.php
index b45c2233..a735dc37 100644
--- a/tests/Unit/Aggregation/Bucketing/CompositeAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/CompositeAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\CompositeAggregation;
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\TermsAggregation;
diff --git a/tests/Unit/Aggregation/Bucketing/DateHistogramAggregationTest.php b/tests/Unit/Aggregation/Bucketing/DateHistogramAggregationTest.php
index 6f7544bb..5fce811a 100644
--- a/tests/Unit/Aggregation/Bucketing/DateHistogramAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/DateHistogramAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\DateHistogramAggregation;
 
@@ -20,11 +20,10 @@ class DateHistogramAggregationTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Tests if ChildrenAggregation#getArray throws exception when expected.
-     *
-     * @expectedException \LogicException
      */
     public function testGetArrayException()
     {
+        $this->expectException(\LogicException::class);
         $aggregation = new DateHistogramAggregation('foo');
         $aggregation->getArray();
     }
diff --git a/tests/Unit/Aggregation/Bucketing/DateRangeAggregationTest.php b/tests/Unit/Aggregation/Bucketing/DateRangeAggregationTest.php
index 6a3c5dbe..c86ebb55 100644
--- a/tests/Unit/Aggregation/Bucketing/DateRangeAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/DateRangeAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\DateRangeAggregation;
 
@@ -17,24 +17,22 @@ class DateRangeAggregationTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Test if exception is thrown.
-     *
-     * @expectedException \LogicException
-     * @expectedExceptionMessage Date range aggregation must have field, format set and range added.
      */
     public function testIfExceptionIsThrownWhenNoParametersAreSet()
     {
+        $this->expectException(\LogicException::class);
+        $this->expectExceptionMessage('Date range aggregation must have field, format set and range added.');
         $agg = new DateRangeAggregation('test_agg');
         $agg->getArray();
     }
 
     /**
      * Test if exception is thrown when both range parameters are null.
-     *
-     * @expectedException \LogicException
-     * @expectedExceptionMessage Either from or to must be set. Both cannot be null.
      */
     public function testIfExceptionIsThrownWhenBothRangesAreNull()
     {
+        $this->expectException(\LogicException::class);
+        $this->expectExceptionMessage('Either from or to must be set. Both cannot be null.');
         $agg = new DateRangeAggregation('test_agg');
         $agg->addRange(null, null);
     }
@@ -73,7 +71,7 @@ public function testDateRangeAggregationGetType()
      *
      * @return array
      */
-    public function testDateRangeAggregationConstructorProvider()
+    public function getDateRangeAggregationConstructorProvider()
     {
         return [
             // Case #0. Minimum arguments.
@@ -112,13 +110,12 @@ public function testDateRangeAggregationConstructorProvider()
      * @param string $format
      * @param array  $ranges
      *
-     * @dataProvider testDateRangeAggregationConstructorProvider
+     * @dataProvider getDateRangeAggregationConstructorProvider
      */
     public function testDateRangeAggregationConstructor($field = null, $format = null, array $ranges = null)
     {
-        /** @var DateRangeAggregation|\PHPUnit_Framework_MockObject_MockObject $aggregation */
         $aggregation = $this->getMockBuilder('ONGR\ElasticsearchDSL\Aggregation\Bucketing\DateRangeAggregation')
-            ->setMethods(['setField', 'setFormat', 'addRange'])
+            ->onlyMethods(['setField', 'setFormat', 'addRange'])
             ->disableOriginalConstructor()
             ->getMock();
         $aggregation->expects($this->once())->method('setField')->with($field);
diff --git a/tests/Unit/Aggregation/Bucketing/FilterAggregationTest.php b/tests/Unit/Aggregation/Bucketing/FilterAggregationTest.php
index b453e014..a5659a59 100644
--- a/tests/Unit/Aggregation/Bucketing/FilterAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/FilterAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\FilterAggregation;
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\HistogramAggregation;
@@ -101,26 +101,35 @@ public function testToArray($aggregation, $expectedResult)
 
     /**
      * Test for setField().
-     *
-     * @expectedException        \LogicException
-     * @expectedExceptionMessage doesn't support `field` parameter
      */
     public function testSetField()
     {
+        $this->expectException(\LogicException::class);
+        $this->expectExceptionMessage('doesn\'t support `field` parameter');
         $aggregation = new FilterAggregation('test_agg');
         $aggregation->setField('test_field');
     }
 
     /**
      * Test for toArray() without setting a filter.
-     *
-     * @expectedException        \LogicException
-     * @expectedExceptionMessage has no filter added
      */
     public function testToArrayNoFilter()
     {
+        $this->expectException(\LogicException::class);
+        $this->expectExceptionMessage('has no filter added');
         $aggregation = new FilterAggregation('test_agg');
-        $aggregation->toArray();
+        $result = $aggregation->toArray();
+
+        $this->assertEquals(
+            [
+                'aggregation' => [
+                    'test_agg' => [
+                        'filter' => []
+                    ]
+                ]
+            ],
+            $result
+        );
     }
 
     /**
@@ -129,9 +138,19 @@ public function testToArrayNoFilter()
     public function testToArrayWithFilter()
     {
         $aggregation = new FilterAggregation('test_agg');
-
         $aggregation->setFilter(new ExistsQuery('test'));
-        $aggregation->toArray();
+        $result = $aggregation->toArray();
+
+        $this->assertEquals(
+            [
+                'filter' => [
+                    'exists' => [
+                        'field' => 'test'
+                    ]
+                ]
+            ],
+            $result
+        );
     }
 
     /**
diff --git a/tests/Unit/Aggregation/Bucketing/FiltersAggregationTest.php b/tests/Unit/Aggregation/Bucketing/FiltersAggregationTest.php
index b3032a31..174bacd8 100644
--- a/tests/Unit/Aggregation/Bucketing/FiltersAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/FiltersAggregationTest.php
@@ -9,10 +9,9 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\FiltersAggregation;
-use ONGR\ElasticsearchDSL\BuilderInterface;
 
 /**
  * Unit test for filters aggregation.
@@ -21,12 +20,11 @@ class FiltersAggregationTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Test if exception is thrown when not anonymous filter is without name.
-     *
-     * @expectedException \LogicException
-     * @expectedExceptionMessage In not anonymous filters filter name must be set.
      */
     public function testIfExceptionIsThrown()
     {
+        $this->expectException(\LogicException::class);
+        $this->expectExceptionMessage('In not anonymous filters filter name must be set.');
         $mock = $this->getMockBuilder('ONGR\ElasticsearchDSL\BuilderInterface')->getMock();
         $aggregation = new FiltersAggregation('test_agg');
         $aggregation->addFilter($mock);
@@ -62,7 +60,7 @@ public function testToArray()
     {
         $aggregation = new FiltersAggregation('test_agg');
         $filter = $this->getMockBuilder('ONGR\ElasticsearchDSL\BuilderInterface')
-            ->setMethods(['toArray', 'getType'])
+            ->onlyMethods(['toArray', 'getType'])
             ->getMockForAbstractClass();
         $filter->expects($this->any())
             ->method('toArray')
@@ -95,9 +93,7 @@ public function testToArray()
      */
     public function testConstructorFilter()
     {
-        /** @var BuilderInterface|\PHPUnit_Framework_MockObject_MockObject $builderInterface1 */
         $builderInterface1 = $this->getMockForAbstractClass('ONGR\ElasticsearchDSL\BuilderInterface');
-        /** @var BuilderInterface|\PHPUnit_Framework_MockObject_MockObject $builderInterface2 */
         $builderInterface2 = $this->getMockForAbstractClass('ONGR\ElasticsearchDSL\BuilderInterface');
 
         $aggregation = new FiltersAggregation(
diff --git a/tests/Unit/Aggregation/Bucketing/GeoDistanceAggregationTest.php b/tests/Unit/Aggregation/Bucketing/GeoDistanceAggregationTest.php
index 89f2f5d5..5f95f6d1 100644
--- a/tests/Unit/Aggregation/Bucketing/GeoDistanceAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/GeoDistanceAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\GeoDistanceAggregation;
 
@@ -17,12 +17,11 @@ class GeoDistanceAggregationTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Test if exception is thrown when field is not set.
-     *
-     * @expectedException \LogicException
-     * @expectedExceptionMessage Geo distance aggregation must have a field set.
      */
     public function testGeoDistanceAggregationExceptionWhenFieldIsNotSet()
     {
+        $this->expectException(\LogicException::class);
+        $this->expectExceptionMessage('Geo distance aggregation must have a field set.');
         $agg = new GeoDistanceAggregation('test_agg');
         $agg->setOrigin('50, 70');
         $agg->getArray();
@@ -30,12 +29,11 @@ public function testGeoDistanceAggregationExceptionWhenFieldIsNotSet()
 
     /**
      * Test if exception is thrown when origin is not set.
-     *
-     * @expectedException \LogicException
-     * @expectedExceptionMessage Geo distance aggregation must have an origin set.
      */
     public function testGeoDistanceAggregationExceptionWhenOriginIsNotSet()
     {
+        $this->expectException(\LogicException::class);
+        $this->expectExceptionMessage('Geo distance aggregation must have an origin set.');
         $agg = new GeoDistanceAggregation('test_agg');
         $agg->setField('location');
         $agg->getArray();
@@ -43,12 +41,11 @@ public function testGeoDistanceAggregationExceptionWhenOriginIsNotSet()
 
     /**
      * Test if exception is thrown when field is not set.
-     *
-     * @expectedException \LogicException
-     * @expectedExceptionMessage Either from or to must be set. Both cannot be null.
      */
     public function testGeoDistanceAggregationAddRangeException()
     {
+        $this->expectException(\LogicException::class);
+        $this->expectExceptionMessage('Either from or to must be set. Both cannot be null.');
         $agg = new GeoDistanceAggregation('test_agg');
         $agg->addRange();
     }
@@ -58,7 +55,7 @@ public function testGeoDistanceAggregationAddRangeException()
      *
      * @return array
      */
-    public function testGeoDistanceAggregationGetArrayDataProvider()
+    public function getGeoDistanceAggregationGetArrayDataProvider()
     {
         $out = [];
         $filterData = [
@@ -88,7 +85,7 @@ public function testGeoDistanceAggregationGetArrayDataProvider()
      * @param array $filterData
      * @param array $expected
      *
-     * @dataProvider testGeoDistanceAggregationGetArrayDataProvider
+     * @dataProvider getGeoDistanceAggregationGetArrayDataProvider
      */
     public function testGeoDistanceAggregationGetArray($filterData, $expected)
     {
diff --git a/tests/Unit/Aggregation/Bucketing/GeoHashGridAggregationTest.php b/tests/Unit/Aggregation/Bucketing/GeoHashGridAggregationTest.php
index 1ef28d34..f2791195 100644
--- a/tests/Unit/Aggregation/Bucketing/GeoHashGridAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/GeoHashGridAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\GeoHashGridAggregation;
 
@@ -20,11 +20,10 @@ class GeoHashGridAggregationTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Test if exception is thrown.
-     *
-     * @expectedException \LogicException
      */
     public function testGeoHashGridAggregationException()
     {
+        $this->expectException(\LogicException::class);
         $agg = new GeoHashGridAggregation('test_agg');
         $agg->getArray();
     }
diff --git a/tests/Unit/Aggregation/Bucketing/GlobalAggregationTest.php b/tests/Unit/Aggregation/Bucketing/GlobalAggregationTest.php
index 725ed283..4e499f6f 100644
--- a/tests/Unit/Aggregation/Bucketing/GlobalAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/GlobalAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\GlobalAggregation;
 
@@ -74,11 +74,10 @@ public function testToArray($aggregation, $expectedResult)
 
     /**
      * Test for setField method on global aggregation.
-     *
-     * @expectedException \LogicException
      */
     public function testSetField()
     {
+        $this->expectException(\LogicException::class);
         $aggregation = new GlobalAggregation('test_agg');
         $aggregation->setField('test_field');
     }
diff --git a/tests/Unit/Aggregation/Bucketing/Ipv4RangeAggregationTest.php b/tests/Unit/Aggregation/Bucketing/Ipv4RangeAggregationTest.php
index 7566efe8..28543c02 100644
--- a/tests/Unit/Aggregation/Bucketing/Ipv4RangeAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/Ipv4RangeAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\Ipv4RangeAggregation;
 
@@ -17,11 +17,10 @@ class Ipv4RangeAggregationTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Test exception when field and range are not set.
-     *
-     * @expectedException \LogicException
      */
     public function testIfExceptionIsThrownWhenFieldAndRangeAreNotSet()
     {
+        $this->expectException(\LogicException::class);
         $agg = new Ipv4RangeAggregation('foo');
         $agg->toArray();
     }
diff --git a/tests/Unit/Aggregation/Bucketing/MissingAggregationTest.php b/tests/Unit/Aggregation/Bucketing/MissingAggregationTest.php
index 613d97ba..d29c4f01 100644
--- a/tests/Unit/Aggregation/Bucketing/MissingAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/MissingAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\MissingAggregation;
 
@@ -17,12 +17,11 @@ class MissingAggregationTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Test if exception is thrown when field is not set.
-     *
-     * @expectedException \LogicException
-     * @expectedExceptionMessage Missing aggregation must have a field set.
      */
     public function testIfExceptionIsThrown()
     {
+        $this->expectException(\LogicException::class);
+        $this->expectExceptionMessage('Missing aggregation must have a field set.');
         $agg = new MissingAggregation('test_agg');
         $agg->getArray();
     }
diff --git a/tests/Unit/Aggregation/Bucketing/NestedAggregationTest.php b/tests/Unit/Aggregation/Bucketing/NestedAggregationTest.php
index b4458f12..cfc4b4f4 100644
--- a/tests/Unit/Aggregation/Bucketing/NestedAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/NestedAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\NestedAggregation;
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\TermsAggregation;
diff --git a/tests/Unit/Aggregation/Bucketing/RangeAggregationTest.php b/tests/Unit/Aggregation/Bucketing/RangeAggregationTest.php
index 55134a86..59f53acd 100644
--- a/tests/Unit/Aggregation/Bucketing/RangeAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/RangeAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\RangeAggregation;
 
diff --git a/tests/Unit/Aggregation/Bucketing/ReverseNestedAggregationTest.php b/tests/Unit/Aggregation/Bucketing/ReverseNestedAggregationTest.php
index 11ed18f7..a88f58b0 100644
--- a/tests/Unit/Aggregation/Bucketing/ReverseNestedAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/ReverseNestedAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\ReverseNestedAggregation;
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\TermsAggregation;
diff --git a/tests/Unit/Aggregation/Bucketing/SamplerAggregationTest.php b/tests/Unit/Aggregation/Bucketing/SamplerAggregationTest.php
index 0bbb209b..a0ee85f5 100644
--- a/tests/Unit/Aggregation/Bucketing/SamplerAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/SamplerAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\SamplerAggregation;
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\TermsAggregation;
diff --git a/tests/Unit/Aggregation/Bucketing/SignificantTermsAggregationTest.php b/tests/Unit/Aggregation/Bucketing/SignificantTermsAggregationTest.php
index c6cf2133..699fb5bb 100644
--- a/tests/Unit/Aggregation/Bucketing/SignificantTermsAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/SignificantTermsAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\SignificantTermsAggregation;
 
diff --git a/tests/Unit/Aggregation/Bucketing/SignificantTextAggregationTest.php b/tests/Unit/Aggregation/Bucketing/SignificantTextAggregationTest.php
index 23b96f3f..d268eefe 100644
--- a/tests/Unit/Aggregation/Bucketing/SignificantTextAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/SignificantTextAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\SignificantTextAggregation;
 
diff --git a/tests/Unit/Aggregation/Bucketing/TermsAggregationTest.php b/tests/Unit/Aggregation/Bucketing/TermsAggregationTest.php
index 47924419..dc46b7df 100644
--- a/tests/Unit/Aggregation/Bucketing/TermsAggregationTest.php
+++ b/tests/Unit/Aggregation/Bucketing/TermsAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Bucketing\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Bucketing;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\TermsAggregation;
 
diff --git a/tests/Unit/Aggregation/Metric/CardinalityAggregationTest.php b/tests/Unit/Aggregation/Metric/CardinalityAggregationTest.php
index 8ec9f2cf..7ebe6d1c 100644
--- a/tests/Unit/Aggregation/Metric/CardinalityAggregationTest.php
+++ b/tests/Unit/Aggregation/Metric/CardinalityAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Metric\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Metric;
 
 use ONGR\ElasticsearchDSL\Aggregation\Metric\CardinalityAggregation;
 
@@ -52,12 +52,11 @@ public function testGetArray()
 
     /**
      * Tests if CardinalityAggregation#getArray throws exception when expected.
-     *
-     * @expectedException \LogicException
-     * @expectedExceptionMessage Cardinality aggregation must have field or script set.
      */
     public function testGetArrayException()
     {
+        $this->expectException(\LogicException::class);
+        $this->expectExceptionMessage('Cardinality aggregation must have field or script set.');
         $aggregation = new CardinalityAggregation('bar');
         $aggregation->getArray();
     }
diff --git a/tests/Unit/Aggregation/Metric/GeoBoundsAggregationTest.php b/tests/Unit/Aggregation/Metric/GeoBoundsAggregationTest.php
index efccb9ba..8e22e071 100644
--- a/tests/Unit/Aggregation/Metric/GeoBoundsAggregationTest.php
+++ b/tests/Unit/Aggregation/Metric/GeoBoundsAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Metric\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Metric;
 
 use ONGR\ElasticsearchDSL\Aggregation\Metric\GeoBoundsAggregation;
 
@@ -20,11 +20,10 @@ class GeoBoundsAggregationTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Test if exception is thrown.
-     *
-     * @expectedException \LogicException
      */
     public function testGeoBoundsAggregationException()
     {
+        $this->expectException(\LogicException::class);
         $agg = new GeoBoundsAggregation('test_agg');
         $agg->getArray();
     }
diff --git a/tests/Unit/Aggregation/Metric/GeoCentroidAggregationTest.php b/tests/Unit/Aggregation/Metric/GeoCentroidAggregationTest.php
index dca14573..759b33f5 100644
--- a/tests/Unit/Aggregation/Metric/GeoCentroidAggregationTest.php
+++ b/tests/Unit/Aggregation/Metric/GeoCentroidAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Metric\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Metric;
 
 use ONGR\ElasticsearchDSL\Aggregation\Metric\GeoCentroidAggregation;
 
@@ -20,11 +20,10 @@ class GeoCentroidAggregationTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Test if exception is thrown when field is not provided
-     *
-     * @expectedException \LogicException
      */
     public function testGetArrayException()
     {
+        $this->expectException(\LogicException::class);
         $aggregation = new GeoCentroidAggregation('foo');
         $aggregation->getArray();
     }
diff --git a/tests/Unit/Aggregation/Metric/PercentileRanksAggregationTest.php b/tests/Unit/Aggregation/Metric/PercentileRanksAggregationTest.php
index 12aeffcc..c4187532 100644
--- a/tests/Unit/Aggregation/Metric/PercentileRanksAggregationTest.php
+++ b/tests/Unit/Aggregation/Metric/PercentileRanksAggregationTest.php
@@ -9,9 +9,10 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Metric\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Metric;
 
 use ONGR\ElasticsearchDSL\Aggregation\Metric\PercentileRanksAggregation;
+use phpDocumentor\Reflection\Types\Void_;
 
 /**
  * Percentile ranks aggregation unit tests.
@@ -26,39 +27,36 @@ class PercentileRanksAggregationTest extends \PHPUnit\Framework\TestCase
     /**
      * Phpunit setup.
      */
-    public function setUp()
+    public function setUp(): void
     {
         $this->agg = new PercentileRanksAggregation('foo');
     }
 
     /**
      * Tests if exception is thrown when required parameters not set.
-     *
-     * @expectedException \LogicException
      */
     public function testIfPercentileRanksAggregationThrowsAnException()
     {
+        $this->expectException(\LogicException::class);
         $this->agg->toArray();
     }
 
     /**
      * Tests exception when only field is set.
-     *
-     * @expectedException \LogicException
      */
     public function testIfExceptionIsThrownWhenFieldSetAndValueNotSet()
     {
+        $this->expectException(\LogicException::class);
         $this->agg->setField('bar');
         $this->agg->toArray();
     }
 
     /**
      * Tests exception when only value is set.
-     *
-     * @expectedException \LogicException
      */
     public function testIfExceptionIsThrownWhenScriptSetAndValueNotSet()
     {
+        $this->expectException(\LogicException::class);
         $this->agg->setScript('bar');
         $this->agg->toArray();
     }
diff --git a/tests/Unit/Aggregation/Metric/PercentilesAggregationTest.php b/tests/Unit/Aggregation/Metric/PercentilesAggregationTest.php
index aa98aa3e..a22b80b8 100644
--- a/tests/Unit/Aggregation/Metric/PercentilesAggregationTest.php
+++ b/tests/Unit/Aggregation/Metric/PercentilesAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Metric\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Metric;
 
 use ONGR\ElasticsearchDSL\Aggregation\Metric\PercentilesAggregation;
 
@@ -17,12 +17,11 @@ class PercentilesAggregationTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Tests if PercentilesAggregation#getArray throws exception when expected.
-     *
-     * @expectedException \LogicException
-     * @expectedExceptionMessage Percentiles aggregation must have field or script set.
      */
     public function testPercentilesAggregationGetArrayException()
     {
+        $this->expectException(\LogicException::class);
+        $this->expectExceptionMessage('Percentiles aggregation must have field or script set.');
         $aggregation = new PercentilesAggregation('bar');
         $aggregation->getArray();
     }
diff --git a/tests/Unit/Aggregation/Metric/StatsAggregationTest.php b/tests/Unit/Aggregation/Metric/StatsAggregationTest.php
index e130641e..991f18e2 100644
--- a/tests/Unit/Aggregation/Metric/StatsAggregationTest.php
+++ b/tests/Unit/Aggregation/Metric/StatsAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Metric\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Metric;
 
 use ONGR\ElasticsearchDSL\Aggregation\Metric\StatsAggregation;
 
diff --git a/tests/Unit/Aggregation/Metric/TopHitsAggregationTest.php b/tests/Unit/Aggregation/Metric/TopHitsAggregationTest.php
index f6018dc8..65824e92 100644
--- a/tests/Unit/Aggregation/Metric/TopHitsAggregationTest.php
+++ b/tests/Unit/Aggregation/Metric/TopHitsAggregationTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Metric\Aggregation;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\Aggregation\Metric;
 
 use ONGR\ElasticsearchDSL\Aggregation\Metric\TopHitsAggregation;
 use ONGR\ElasticsearchDSL\Sort\FieldSort;
diff --git a/tests/Unit/Aggregation/Pipeline/BucketScriptAggregationTest.php b/tests/Unit/Aggregation/Pipeline/BucketScriptAggregationTest.php
index 16c85b62..9754ab46 100644
--- a/tests/Unit/Aggregation/Pipeline/BucketScriptAggregationTest.php
+++ b/tests/Unit/Aggregation/Pipeline/BucketScriptAggregationTest.php
@@ -50,12 +50,11 @@ public function testToArray()
     /**
      * Tests if the exception is thrown in getArray method if no
      * buckets_path or script is set
-     *
-     * @expectedException \LogicException
-     * @expectedExceptionMessage `test` aggregation must have script set.
      */
     public function testGetArrayException()
     {
+        $this->expectException(\LogicException::class);
+        $this->expectExceptionMessage('`test` aggregation must have script set.');
         $agg = new BucketScriptAggregation('test', []);
 
         $agg->getArray();
diff --git a/tests/Unit/Aggregation/Pipeline/BucketSelectorAggregationTest.php b/tests/Unit/Aggregation/Pipeline/BucketSelectorAggregationTest.php
index c8edbc9c..83a45453 100644
--- a/tests/Unit/Aggregation/Pipeline/BucketSelectorAggregationTest.php
+++ b/tests/Unit/Aggregation/Pipeline/BucketSelectorAggregationTest.php
@@ -48,12 +48,11 @@ public function testToArray()
     /**
      * Tests if the exception is thrown in getArray method if no
      * buckets_path or script is set
-     *
-     * @expectedException \LogicException
-     * @expectedExceptionMessage `test` aggregation must have script set.
      */
     public function testGetArrayException()
     {
+        $this->expectException(\LogicException::class);
+        $this->expectExceptionMessage('`test` aggregation must have script set.');
         $agg = new BucketSelectorAggregation('test', []);
 
         $agg->getArray();
diff --git a/tests/Unit/BuilderBagTest.php b/tests/Unit/BuilderBagTest.php
index 49d6a2ff..7749c4c4 100644
--- a/tests/Unit/BuilderBagTest.php
+++ b/tests/Unit/BuilderBagTest.php
@@ -13,6 +13,7 @@
 
 use ONGR\ElasticsearchDSL\BuilderBag;
 use ONGR\ElasticsearchDSL\BuilderInterface;
+use PHPUnit\Framework\MockObject\MockBuilder;
 
 class BuilderBagTest extends \PHPUnit\Framework\TestCase
 {
@@ -79,12 +80,13 @@ public function testGet()
      *
      * @param string $name
      *
-     * @return \PHPUnit_Framework_MockObject_MockObject|BuilderInterface
+     * @return MockBuilder|BuilderInterface
      */
     private function getBuilder($name)
     {
         $friendlyBuilderMock = $this->getMockBuilder('ONGR\ElasticsearchDSL\BuilderInterface')
-            ->setMethods(['getName', 'toArray', 'getType'])
+            ->onlyMethods(['toArray', 'getType'])
+            ->addMethods(['getName'])
             ->disableOriginalConstructor()
             ->getMock();
 
diff --git a/tests/Unit/ParametersTraitTest.php b/tests/Unit/ParametersTraitTest.php
index d456e288..cd9c25d7 100644
--- a/tests/Unit/ParametersTraitTest.php
+++ b/tests/Unit/ParametersTraitTest.php
@@ -11,6 +11,7 @@
 
 namespace ONGR\ElasticsearchDSL\Tests\Unit;
 
+use ONGR\ElasticsearchDSL\Aggregation\AbstractAggregation;
 use ONGR\ElasticsearchDSL\ParametersTrait;
 
 /**
@@ -26,7 +27,7 @@ class ParametersTraitTest extends \PHPUnit\Framework\TestCase
     /**
      * {@inheritdoc}
      */
-    public function setUp()
+    public function setUp(): void
     {
         $this->parametersTraitMock = $this->getMockForTrait('ONGR\ElasticsearchDSL\ParametersTrait');
     }
@@ -36,9 +37,10 @@ public function setUp()
      */
     public function testGetAndAddParameter()
     {
-        $this->parametersTraitMock->addParameter('acme', 123);
+        $this->assertTrue(is_object($this->parametersTraitMock->addParameter('acme', 123)));
         $this->assertEquals(123, $this->parametersTraitMock->getParameter('acme'));
         $this->parametersTraitMock->addParameter('bar', 321);
         $this->assertEquals(321, $this->parametersTraitMock->getParameter('bar'));
+        $this->assertTrue(is_object($this->parametersTraitMock->removeParameter('acme')));
     }
 }
diff --git a/tests/Unit/Query/Compound/BoolQueryTest.php b/tests/Unit/Query/Compound/BoolQueryTest.php
index 93fe2db7..959ca075 100644
--- a/tests/Unit/Query/Compound/BoolQueryTest.php
+++ b/tests/Unit/Query/Compound/BoolQueryTest.php
@@ -22,12 +22,11 @@ class BoolQueryTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Test for addToBool() without setting a correct bool operator.
-     *
-     * @expectedException        \UnexpectedValueException
-     * @expectedExceptionMessage The bool operator acme is not supported
      */
     public function testBoolAddToBoolException()
     {
+        $this->expectException(\UnexpectedValueException::class);
+        $this->expectExceptionMessage('The bool operator acme is not supported');
         $bool = new BoolQuery();
         $bool->add(new MatchAllQuery(), 'acme');
     }
@@ -81,12 +80,11 @@ public function testBoolConstructor()
 
     /**
      * Tests exception thrown if invalid BoolQuery type key is specified
-     *
-     * @expectedException        \UnexpectedValueException
-     * @expectedExceptionMessage The bool operator acme is not supported
      */
     public function testBoolConstructorException()
     {
+        $this->expectException(\UnexpectedValueException::class);
+        $this->expectExceptionMessage('The bool operator acme is not supported');
         new BoolQuery([
             'acme' => [new TermQuery('key1', 'value1')],
         ]);
@@ -190,7 +188,7 @@ public function testGetQueriesEmpty()
     {
         $bool = new BoolQuery();
 
-        $this->assertInternalType('array', $bool->getQueries());
+        $this->assertIsArray($bool->getQueries());
     }
 
     /**
@@ -215,7 +213,7 @@ public function testGetQueriesByBoolTypeEmpty()
     {
         $bool = new BoolQuery();
 
-        $this->assertInternalType('array', $bool->getQueries(BoolQuery::MUST));
+        $this->assertIsArray($bool->getQueries(BoolQuery::MUST));
     }
 
     /**
diff --git a/tests/Unit/Query/Compound/FunctionScoreQueryTest.php b/tests/Unit/Query/Compound/FunctionScoreQueryTest.php
index 9997b0b7..7904aa72 100644
--- a/tests/Unit/Query/Compound/FunctionScoreQueryTest.php
+++ b/tests/Unit/Query/Compound/FunctionScoreQueryTest.php
@@ -11,10 +11,8 @@
 
 namespace ONGR\ElasticsearchDSL\Tests\Unit\Query\Compound;
 
-use ONGR\ElasticsearchDSL\BuilderInterface;
 use ONGR\ElasticsearchDSL\Query\Compound\FunctionScoreQuery;
 use ONGR\ElasticsearchDSL\Query\MatchAllQuery;
-use PHPUnit_Framework_MockObject_MockObject as MockObject;
 
 /**
  * Tests for FunctionScoreQuery.
@@ -66,21 +64,19 @@ public function addRandomFunctionProvider()
      */
     public function testAddRandomFunction($seed, $expectedArray)
     {
-        /** @var MatchAllQuery|MockObject $matchAllQuery */
-        $matchAllQuery = $this->getMockBuilder('ONGR\ElasticsearchDSL\Query\MatchAllQuery')->getMock();
+        $matchAllQuery = $this->getMockBuilder(MatchAllQuery::class)->getMock();
 
         $functionScoreQuery = new FunctionScoreQuery($matchAllQuery);
         $functionScoreQuery->addRandomFunction($seed);
 
         $this->assertEquals(['function_score' => $expectedArray], $functionScoreQuery->toArray());
     }
-    
+
     /**
      * Tests default argument values.
      */
     public function testAddFieldValueFactorFunction()
     {
-        /** @var BuilderInterface|MockObject $builderInterface */
         $builderInterface = $this->getMockForAbstractClass('ONGR\ElasticsearchDSL\BuilderInterface');
         $functionScoreQuery = new FunctionScoreQuery($builderInterface);
         $functionScoreQuery->addFieldValueFactorFunction('field1', 2);
diff --git a/tests/Unit/Query/Geo/GeoBoundingBoxQueryTest.php b/tests/Unit/Query/Geo/GeoBoundingBoxQueryTest.php
index bc9c01b1..6ff94107 100644
--- a/tests/Unit/Query/Geo/GeoBoundingBoxQueryTest.php
+++ b/tests/Unit/Query/Geo/GeoBoundingBoxQueryTest.php
@@ -17,11 +17,10 @@ class GeoBoundingBoxQueryTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Test if exception is thrown when geo points are not set.
-     *
-     * @expectedException \LogicException
      */
     public function testGeoBoundBoxQueryException()
     {
+        $this->expectException(\LogicException::class);
         $query = new GeoBoundingBoxQuery('location', []);
         $query->toArray();
     }
diff --git a/tests/Unit/Query/Span/SpanContainingQueryTest.php b/tests/Unit/Query/Span/SpanContainingQueryTest.php
index 71411abf..a6cd16a0 100644
--- a/tests/Unit/Query/Span/SpanContainingQueryTest.php
+++ b/tests/Unit/Query/Span/SpanContainingQueryTest.php
@@ -12,6 +12,7 @@
 namespace ONGR\ElasticsearchDSL\Tests\Unit\Query\Span;
 
 use ONGR\ElasticsearchDSL\Query\Span\SpanContainingQuery;
+use PHPUnit\Framework\MockObject\MockBuilder;
 
 /**
  * Unit test for SpanContainingQuery.
@@ -43,7 +44,7 @@ public function testToArray()
     /**
      * @param string $value
      *
-     * @returns \PHPUnit_Framework_MockObject_MockObject
+     * @returns MockBuilder
      */
     private function getSpanQueryMock($value)
     {
diff --git a/tests/Unit/Query/Span/SpanOrQueryTest.php b/tests/Unit/Query/Span/SpanOrQueryTest.php
index 537caf44..6aa203d3 100644
--- a/tests/Unit/Query/Span/SpanOrQueryTest.php
+++ b/tests/Unit/Query/Span/SpanOrQueryTest.php
@@ -43,7 +43,7 @@ public function testToArray()
         $this->assertEquals($result, $query->toArray());
 
         $result = $query->getQueries();
-        $this->assertInternalType('array', $result);
+        $this->assertIsArray($result);
         $this->assertEquals(1, count($result));
     }
 }
diff --git a/tests/Unit/Query/Span/SpanWithinQueryTest.php b/tests/Unit/Query/Span/SpanWithinQueryTest.php
index d0a7c160..550e37be 100644
--- a/tests/Unit/Query/Span/SpanWithinQueryTest.php
+++ b/tests/Unit/Query/Span/SpanWithinQueryTest.php
@@ -12,6 +12,7 @@
 namespace ONGR\ElasticsearchDSL\Tests\Unit\Query\Span;
 
 use ONGR\ElasticsearchDSL\Query\Span\SpanWithinQuery;
+use PHPUnit\Framework\MockObject\MockBuilder;
 
 /**
  * Unit test for SpanWithinQuery.
@@ -43,7 +44,7 @@ public function testToArray()
     /**
      * @param string $value
      *
-     * @returns \PHPUnit_Framework_MockObject_MockObject
+     * @returns MockBuilder
      */
     private function getSpanQueryMock($value)
     {
diff --git a/tests/Unit/Query/Specialized/TemplateQueryTest.php b/tests/Unit/Query/Specialized/TemplateQueryTest.php
index 80e497a5..12c6e0d8 100644
--- a/tests/Unit/Query/Specialized/TemplateQueryTest.php
+++ b/tests/Unit/Query/Specialized/TemplateQueryTest.php
@@ -56,11 +56,10 @@ public function testToArrayFile()
 
     /**
      * Tests toArray() exception
-     *
-     * @expectedException \InvalidArgumentException
      */
     public function testToArrayException()
     {
+        $this->expectException(\InvalidArgumentException::class);
         $query = new TemplateQuery();
         $query->toArray();
     }
diff --git a/tests/Unit/SearchEndpoint/AggregationsEndpointTest.php b/tests/Unit/SearchEndpoint/AggregationsEndpointTest.php
index 016c1ff7..bc7489fd 100644
--- a/tests/Unit/SearchEndpoint/AggregationsEndpointTest.php
+++ b/tests/Unit/SearchEndpoint/AggregationsEndpointTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Unit\SearchEndpoint;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\SearchEndpoint;
 
 use ONGR\ElasticsearchDSL\Aggregation\Bucketing\MissingAggregation;
 use ONGR\ElasticsearchDSL\SearchEndpoint\AggregationsEndpoint;
diff --git a/tests/Unit/SearchEndpoint/HighlightEndpointTest.php b/tests/Unit/SearchEndpoint/HighlightEndpointTest.php
index 5b1a623f..6306b694 100644
--- a/tests/Unit/SearchEndpoint/HighlightEndpointTest.php
+++ b/tests/Unit/SearchEndpoint/HighlightEndpointTest.php
@@ -9,12 +9,11 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Unit\SearchEndpoint;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\SearchEndpoint;
 
 use ONGR\ElasticsearchDSL\Highlight\Highlight;
 use ONGR\ElasticsearchDSL\SearchEndpoint\HighlightEndpoint;
 use Symfony\Component\Serializer\Normalizer\NormalizerInterface;
-use PHPUnit_Framework_MockObject_MockObject as MockObject;
 
 /**
  * Class HighlightEndpointTest.
@@ -26,7 +25,7 @@ class HighlightEndpointTest extends \PHPUnit\Framework\TestCase
      */
     public function testItCanBeInstantiated()
     {
-        $this->assertInstanceOf('ONGR\ElasticsearchDSL\SearchEndpoint\HighlightEndpoint', new HighlightEndpoint());
+        $this->assertInstanceOf(HighlightEndpoint::class, new HighlightEndpoint());
     }
 
     /**
@@ -35,9 +34,8 @@ public function testItCanBeInstantiated()
     public function testNormalization()
     {
         $instance = new HighlightEndpoint();
-        /** @var NormalizerInterface|MockObject $normalizerInterface */
         $normalizerInterface = $this->getMockForAbstractClass(
-            'Symfony\Component\Serializer\Normalizer\NormalizerInterface'
+            NormalizerInterface::class
         );
 
         $this->assertNull($instance->normalize($normalizerInterface));
diff --git a/tests/Unit/SearchEndpoint/InnerHitsEndpointTest.php b/tests/Unit/SearchEndpoint/InnerHitsEndpointTest.php
index 26e2a7a3..c726cbdf 100644
--- a/tests/Unit/SearchEndpoint/InnerHitsEndpointTest.php
+++ b/tests/Unit/SearchEndpoint/InnerHitsEndpointTest.php
@@ -9,7 +9,7 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Unit\SearchEndpoint;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\SearchEndpoint;
 
 use ONGR\ElasticsearchDSL\SearchEndpoint\InnerHitsEndpoint;
 
@@ -54,7 +54,8 @@ public function testNormalization()
             ->getMock();
         $innerHit = $this
             ->getMockBuilder('ONGR\ElasticsearchDSL\BuilderInterface')
-            ->setMethods(['getName', 'toArray', 'getType'])
+            ->onlyMethods(['toArray', 'getType'])
+            ->addMethods(['getName'])
             ->getMock();
         $innerHit->expects($this->any())->method('getName')->willReturn('foo');
         $innerHit->expects($this->any())->method('toArray')->willReturn(['foo' => 'bar']);
diff --git a/tests/Unit/SearchEndpoint/PostFilterEndpointTest.php b/tests/Unit/SearchEndpoint/PostFilterEndpointTest.php
index 36adfc3e..52cdb05e 100644
--- a/tests/Unit/SearchEndpoint/PostFilterEndpointTest.php
+++ b/tests/Unit/SearchEndpoint/PostFilterEndpointTest.php
@@ -9,12 +9,10 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Unit\SearchEndpoint;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\SearchEndpoint;
 
 use ONGR\ElasticsearchDSL\Query\MatchAllQuery;
 use ONGR\ElasticsearchDSL\SearchEndpoint\PostFilterEndpoint;
-use Symfony\Component\Serializer\Normalizer\NormalizerInterface;
-use PHPUnit_Framework_MockObject_MockObject as MockObject;
 
 /**
  * Class PostFilterEndpointTest.
@@ -44,7 +42,6 @@ public function testGetOrder()
     public function testNormalization()
     {
         $instance = new PostFilterEndpoint();
-        /** @var NormalizerInterface|MockObject $normalizerInterface */
         $normalizerInterface = $this->getMockForAbstractClass(
             'Symfony\Component\Serializer\Normalizer\NormalizerInterface'
         );
diff --git a/tests/Unit/SearchEndpoint/QueryEndpointTest.php b/tests/Unit/SearchEndpoint/QueryEndpointTest.php
index 5d28e152..a72813c8 100644
--- a/tests/Unit/SearchEndpoint/QueryEndpointTest.php
+++ b/tests/Unit/SearchEndpoint/QueryEndpointTest.php
@@ -9,12 +9,10 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Unit\SearchEndpoint;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\SearchEndpoint;
 
 use ONGR\ElasticsearchDSL\Query\MatchAllQuery;
 use ONGR\ElasticsearchDSL\SearchEndpoint\QueryEndpoint;
-use PHPUnit_Framework_MockObject_MockObject as MockObject;
-use Symfony\Component\Serializer\Normalizer\NormalizerInterface;
 
 /**
  * Unit test class for the QueryEndpoint.
@@ -44,7 +42,6 @@ public function testGetOrder()
     public function testEndpoint()
     {
         $instance = new QueryEndpoint();
-        /** @var NormalizerInterface|MockObject $normalizerInterface */
         $normalizerInterface = $this->getMockForAbstractClass(
             'Symfony\Component\Serializer\Normalizer\NormalizerInterface'
         );
diff --git a/tests/Unit/SearchEndpoint/SearchEndpointFactoryTest.php b/tests/Unit/SearchEndpoint/SearchEndpointFactoryTest.php
index b33028bb..8b350909 100644
--- a/tests/Unit/SearchEndpoint/SearchEndpointFactoryTest.php
+++ b/tests/Unit/SearchEndpoint/SearchEndpointFactoryTest.php
@@ -9,10 +9,11 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Unit\SearchEndpoint;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\SearchEndpoint;
 
 use ONGR\ElasticsearchDSL\SearchEndpoint\AggregationsEndpoint;
 use ONGR\ElasticsearchDSL\SearchEndpoint\SearchEndpointFactory;
+use ONGR\ElasticsearchDSL\SearchEndpoint\SearchEndpointInterface;
 
 /**
  * Unit test class for search endpoint factory.
@@ -21,11 +22,10 @@ class SearchEndpointFactoryTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Tests get method exception.
-     *
-     * @expectedException \RuntimeException
      */
     public function testGet()
     {
+        $this->expectException(\RuntimeException::class);
         SearchEndpointFactory::get('foo');
     }
 
@@ -34,6 +34,7 @@ public function testGet()
      */
     public function testFactory()
     {
-        SearchEndpointFactory::get(AggregationsEndpoint::NAME);
+        $endpoint = SearchEndpointFactory::get(AggregationsEndpoint::NAME);
+        $this->assertInstanceOf(SearchEndpointInterface::class, $endpoint);
     }
 }
diff --git a/tests/Unit/SearchEndpoint/SortEndpointTest.php b/tests/Unit/SearchEndpoint/SortEndpointTest.php
index 7f825bcf..0bafd84a 100644
--- a/tests/Unit/SearchEndpoint/SortEndpointTest.php
+++ b/tests/Unit/SearchEndpoint/SortEndpointTest.php
@@ -9,12 +9,10 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Unit\SearchEndpoint;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\SearchEndpoint;
 
 use ONGR\ElasticsearchDSL\SearchEndpoint\SortEndpoint;
 use ONGR\ElasticsearchDSL\Sort\FieldSort;
-use PHPUnit_Framework_MockObject_MockObject as MockObject;
-use Symfony\Component\Serializer\Normalizer\NormalizerInterface;
 
 /**
  * Class SortEndpointTest.
@@ -36,7 +34,6 @@ public function testNormalize()
     {
         $instance = new SortEndpoint();
 
-        /** @var NormalizerInterface|MockObject $normalizerInterface */
         $normalizerInterface = $this->getMockForAbstractClass(
             'Symfony\Component\Serializer\Normalizer\NormalizerInterface'
         );
diff --git a/tests/Unit/SearchEndpoint/SuggestEndpointTest.php b/tests/Unit/SearchEndpoint/SuggestEndpointTest.php
index 34c8704b..41b0550c 100644
--- a/tests/Unit/SearchEndpoint/SuggestEndpointTest.php
+++ b/tests/Unit/SearchEndpoint/SuggestEndpointTest.php
@@ -9,12 +9,10 @@
  * file that was distributed with this source code.
  */
 
-namespace ONGR\ElasticsearchDSL\Tests\Unit\Unit\SearchEndpoint;
+namespace ONGR\ElasticsearchDSL\Tests\Unit\SearchEndpoint;
 
 use ONGR\ElasticsearchDSL\SearchEndpoint\SuggestEndpoint;
 use ONGR\ElasticsearchDSL\Suggest\Suggest;
-use PHPUnit_Framework_MockObject_MockObject as MockObject;
-use Symfony\Component\Serializer\Normalizer\NormalizerInterface;
 
 class SuggestEndpointTest extends \PHPUnit\Framework\TestCase
 {
@@ -49,7 +47,6 @@ public function testNormalize()
     {
         $instance = new SuggestEndpoint();
 
-        /** @var NormalizerInterface|MockObject $normalizerInterface */
         $normalizerInterface = $this->getMockForAbstractClass(
             'Symfony\Component\Serializer\Normalizer\NormalizerInterface'
         );
diff --git a/tests/Unit/Sort/FieldSortTest.php b/tests/Unit/Sort/FieldSortTest.php
index d8863785..8219283b 100644
--- a/tests/Unit/Sort/FieldSortTest.php
+++ b/tests/Unit/Sort/FieldSortTest.php
@@ -19,7 +19,6 @@ class FieldSortTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Test for toArray() method.
-     *
      */
     public function testToArray()
     {
diff --git a/tests/Unit/Sort/NestedSortTest.php b/tests/Unit/Sort/NestedSortTest.php
index 5fb970f1..e49640dc 100644
--- a/tests/Unit/Sort/NestedSortTest.php
+++ b/tests/Unit/Sort/NestedSortTest.php
@@ -18,7 +18,6 @@ class NestedSortTest extends \PHPUnit\Framework\TestCase
 {
     /**
      * Test for single nested.
-     *
      */
     public function testSingle()
     {
@@ -37,7 +36,6 @@ public function testSingle()
 
     /**
      * Test for single nested, no filter.
-     *
      */
     public function testNoFilter()
     {
@@ -51,7 +49,6 @@ public function testNoFilter()
 
     /**
      * Test for single nested.
-     *
      */
     public function testMultipleNesting()
     {
diff --git a/tests/Unit/Suggest/SuggestTest.php b/tests/Unit/Suggest/SuggestTest.php
index 7ae17892..829ae0dc 100644
--- a/tests/Unit/Suggest/SuggestTest.php
+++ b/tests/Unit/Suggest/SuggestTest.php
@@ -26,8 +26,6 @@ public function testSuggestGetType()
 
     /**
      * Data provider for testToArray()
-     *
-     * @return array[]
      */
     public function getTestToArrayData()
     {