Made code compatible with PHP 5.6 and with older version of PHPUnit.

Author: hostep

app/code/Magento/Ui/Model/UiComponentTypeResolver.php

@@ -38,9 +38,11 @@ public function __construct(array $uiComponentTypeMap)
      * @param UiComponentContext $componentContext
      * @return string
      */
-    public function resolve(UiComponentContext $componentContext): string
+    public function resolve(UiComponentContext $componentContext)
     {
         $acceptType = $componentContext->getAcceptType();
-        return $this->uiComponentTypeMap[$acceptType] ?? static::DEFAULT_CONTENT_TYPE;
+        return isset($this->uiComponentTypeMap[$acceptType])
+            ? $this->uiComponentTypeMap[$acceptType]
+            : static::DEFAULT_CONTENT_TYPE;
     }
 }

app/code/Magento/Ui/Test/Unit/Controller/Adminhtml/Index/RenderTest.php

@@ -143,7 +143,7 @@ public function testExecuteAjaxRequest()
             true,
             ['render']
         );
-        $contextMock = $this->createMock(ContextInterface::class);
+        $contextMock = $this->getMock(ContextInterface::class);
 
         $viewMock->expects($this->once())
             ->method('render')
@@ -197,6 +197,8 @@ public function testExecuteAjaxRequestWithoutPermissions($acl, $isAllowed)
             true,
             ['render']
         );
+        $contextMock = $this->getMock(ContextInterface::class);
+
         $componentMock->expects($this->any())
             ->method('render')
             ->willReturn($renderedData);
@@ -207,6 +209,9 @@ public function testExecuteAjaxRequestWithoutPermissions($acl, $isAllowed)
             ->method('getData')
             ->with('acl')
             ->willReturn($acl);
+        $componentMock->expects($this->any())
+            ->method('getContext')
+            ->willReturn($contextMock);
         $this->uiFactoryMock->expects($this->once())
             ->method('create')
             ->willReturn($componentMock);

app/code/Magento/Ui/Test/Unit/Model/UiComponentTypeResolverTest.php

@@ -8,7 +8,7 @@
 use Magento\Ui\Model\UiComponentTypeResolver;
 use Magento\Framework\View\Element\UiComponent\ContextInterface;
 
-class UiComponentTypeResolverTest extends \PHPUnit\Framework\TestCase
+class UiComponentTypeResolverTest extends \PHPUnit_Framework_TestCase
 {
     /**
      * @var UiComponentTypeResolver
@@ -35,9 +35,9 @@ protected function setUp()
      * @param string $contentType
      * @dataProvider resolveDataProvider
      */
-    public function testResolve(string $acceptType, string $contentType)
+    public function testResolve($acceptType, $contentType)
     {
-        $uiComponentContextMock = $this->createMock(ContextInterface::class);
+        $uiComponentContextMock = $this->getMock(ContextInterface::class);
         $uiComponentContextMock->expects($this->atLeastOnce())->method('getAcceptType')->willReturn($acceptType);
 
         $this->assertEquals($contentType, $this->model->resolve($uiComponentContextMock));
@@ -46,7 +46,7 @@ public function testResolve(string $acceptType, string $contentType)
     /**
      * @return array
      */
-    public function resolveDataProvider(): array
+    public function resolveDataProvider()
     {
         return [
             ['json', 'application/json'],