diff --git a/tasks/phpstan/extensions/PHPUnit5CompatExtension/Type/CreateMockDynamicReturnTypeExtension.php b/tasks/phpstan/extensions/PHPUnit5CompatExtension/Type/CreateMockDynamicReturnTypeExtension.php
deleted file mode 100644
index 6f02aee1fe..0000000000
--- a/tasks/phpstan/extensions/PHPUnit5CompatExtension/Type/CreateMockDynamicReturnTypeExtension.php
+++ /dev/null
@@ -1,9 +0,0 @@
-<?php
-
-namespace MailPoet\PHPStan\Extensions\PHPUnit5CompatExtension\Type;
-
-class CreateMockDynamicReturnTypeExtension extends \PHPStan\Type\PHPUnit\CreateMockDynamicReturnTypeExtension {
-  public function getClass(): string {
-    return 'PHPUnit_Framework_TestCase';
-  }
-}
diff --git a/tasks/phpstan/extensions/PHPUnit5CompatExtension/Type/GetMockBuilderDynamicReturnTypeExtension.php b/tasks/phpstan/extensions/PHPUnit5CompatExtension/Type/GetMockBuilderDynamicReturnTypeExtension.php
deleted file mode 100644
index 8dd44a8187..0000000000
--- a/tasks/phpstan/extensions/PHPUnit5CompatExtension/Type/GetMockBuilderDynamicReturnTypeExtension.php
+++ /dev/null
@@ -1,9 +0,0 @@
-<?php
-
-namespace MailPoet\PHPStan\Extensions\PHPUnit5CompatExtension\Type;
-
-class GetMockBuilderDynamicReturnTypeExtension extends \PHPStan\Type\PHPUnit\GetMockBuilderDynamicReturnTypeExtension {
-  public function getClass(): string {
-    return 'PHPUnit_Framework_TestCase';
-  }
-}
diff --git a/tasks/phpstan/extensions/PHPUnit5CompatExtension/Type/MockBuilderDynamicReturnTypeExtension.php b/tasks/phpstan/extensions/PHPUnit5CompatExtension/Type/MockBuilderDynamicReturnTypeExtension.php
new file mode 100644
index 0000000000..42104c5bd6
--- /dev/null
+++ b/tasks/phpstan/extensions/PHPUnit5CompatExtension/Type/MockBuilderDynamicReturnTypeExtension.php
@@ -0,0 +1,11 @@
+<?php
+
+namespace MailPoet\PHPStan\Extensions\PHPUnit5CompatExtension\Type;
+
+use PHPUnit_Framework_MockObject_MockBuilder;
+
+class MockBuilderDynamicReturnTypeExtension extends \PHPStan\Type\PHPUnit\MockBuilderDynamicReturnTypeExtension {
+  public function getClass(): string {
+    return PHPUnit_Framework_MockObject_MockBuilder::class;
+  }
+}
diff --git a/tasks/phpstan/extensions/PHPUnit5CompatExtension/extension.neon b/tasks/phpstan/extensions/PHPUnit5CompatExtension/extension.neon
index 11c638ca54..887a03f5d3 100644
--- a/tasks/phpstan/extensions/PHPUnit5CompatExtension/extension.neon
+++ b/tasks/phpstan/extensions/PHPUnit5CompatExtension/extension.neon
@@ -4,16 +4,13 @@ parameters:
       - fail
       - markTestIncomplete
       - markTestSkipped
+  stubFiles:
+    - stubs/MockBuilder.php
+    - stubs/MockObject.php
+    - stubs/TestCase.php
 
 services:
-  # resolves return type from $this->createMock(SomeMockedClass::class) and other methods in PHPUnit_Framework_TestCase
   -
-    class: MailPoet\PHPStan\Extensions\PHPUnit5CompatExtension\Type\CreateMockDynamicReturnTypeExtension
-    tags:
-      - phpstan.broker.dynamicMethodReturnTypeExtension
-
-  # resolves return type from $this->getMockBuilder(SomeMockedClass::class) in PHPUnit_Framework_TestCase
-  -
-    class: MailPoet\PHPStan\Extensions\PHPUnit5CompatExtension\Type\GetMockBuilderDynamicReturnTypeExtension
+    class: MailPoet\PHPStan\Extensions\PHPUnit5CompatExtension\Type\MockBuilderDynamicReturnTypeExtension
     tags:
       - phpstan.broker.dynamicMethodReturnTypeExtension
diff --git a/tasks/phpstan/extensions/PHPUnit5CompatExtension/stubs/MockBuilder.php b/tasks/phpstan/extensions/PHPUnit5CompatExtension/stubs/MockBuilder.php
new file mode 100644
index 0000000000..31ab413f42
--- /dev/null
+++ b/tasks/phpstan/extensions/PHPUnit5CompatExtension/stubs/MockBuilder.php
@@ -0,0 +1,26 @@
+<?php
+
+/**
+ * @template TMockedClass
+ */
+class PHPUnit_Framework_MockObject_MockBuilder { // phpcs:ignore
+
+  /**
+   * @phpstan-param PHPUnit_Framework_TestCase $testCase
+   * @phpstan-param class-string<TMockedClass> $type
+   */
+  public function __construct(PHPUnit_Framework_TestCase $testCase, $type) {
+  }
+
+  /**
+   * @phpstan-return PHPUnit_Framework_MockObject_MockObject&TMockedClass
+   */
+  public function getMock() {
+  }
+
+  /**
+   * @phpstan-return PHPUnit_Framework_MockObject_MockObject&TMockedClass
+   */
+  public function getMockForAbstractClass() {
+  }
+}
diff --git a/tasks/phpstan/extensions/PHPUnit5CompatExtension/stubs/MockObject.php b/tasks/phpstan/extensions/PHPUnit5CompatExtension/stubs/MockObject.php
new file mode 100644
index 0000000000..d008458806
--- /dev/null
+++ b/tasks/phpstan/extensions/PHPUnit5CompatExtension/stubs/MockObject.php
@@ -0,0 +1,4 @@
+<?php
+
+interface PHPUnit_Framework_MockObject_MockObject { // phpcs:ignore
+}
diff --git a/tasks/phpstan/extensions/PHPUnit5CompatExtension/stubs/TestCase.php b/tasks/phpstan/extensions/PHPUnit5CompatExtension/stubs/TestCase.php
new file mode 100644
index 0000000000..657a649991
--- /dev/null
+++ b/tasks/phpstan/extensions/PHPUnit5CompatExtension/stubs/TestCase.php
@@ -0,0 +1,78 @@
+<?php
+
+class PHPUnit_Framework_TestCase { // phpcs:ignore
+  /**
+   * @template T
+   * @phpstan-param class-string<T> $originalClassName
+   * @phpstan-return PHPUnit_Framework_MockObject_MockObject&T
+   */
+  public function createStub($originalClassName) {
+  }
+
+  /**
+   * @template T
+   * @phpstan-param class-string<T> $originalClassName
+   * @phpstan-return PHPUnit_Framework_MockObject_MockObject&T
+   */
+  public function createMock($originalClassName) {
+  }
+
+  /**
+   * @template T
+   * @phpstan-param class-string<T> $className
+   * @phpstan-return PHPUnit_Framework_MockObject_MockBuilder<T>
+   */
+  public function getMockBuilder(string $className) {
+  }
+
+  /**
+   * @template T
+   * @phpstan-param class-string<T> $originalClassName
+   * @phpstan-return PHPUnit_Framework_MockObject_MockObject&T
+   */
+  public function createConfiguredMock($originalClassName) {
+  }
+
+  /**
+   * @template T
+   * @phpstan-param class-string<T> $originalClassName
+   * @phpstan-param string[] $methods
+   * @phpstan-return PHPUnit_Framework_MockObject_MockObject&T
+   */
+  public function createPartialMock($originalClassName, array $methods) {
+  }
+
+  /**
+   * @template T
+   * @phpstan-param class-string<T> $originalClassName
+   * @phpstan-return PHPUnit_Framework_MockObject_MockObject&T
+   */
+  public function createTestProxy($originalClassName) {
+  }
+
+  /**
+   * @template T
+   * @phpstan-param class-string<T> $originalClassName
+   * @phpstan-param string $mockClassName
+   * @phpstan-param bool $callOriginalConstructor
+   * @phpstan-param bool $callOriginalClone
+   * @phpstan-param bool $callAutoload
+   * @phpstan-param string[] $mockedMethods
+   * @phpstan-param bool $cloneArguments
+   * @phpstan-return PHPUnit_Framework_MockObject_MockObject&T
+   */
+  protected function getMockForAbstractClass($originalClassName, array $arguments = [], $mockClassName = '', $callOriginalConstructor = true, $callOriginalClone = true, $callAutoload = true, $mockedMethods = [], $cloneArguments = false) {
+  }
+
+  /**
+   * @template T
+   * @phpstan-param string $wsdlFile
+   * @phpstan-param class-string<T> $originalClassName
+   * @phpstan-param string $mockClassName
+   * @phpstan-param bool $callOriginalConstructor
+   * @phpstan-param array $options
+   * @phpstan-return PHPUnit_Framework_MockObject_MockObject&T
+   */
+  protected function getMockFromWsdl($wsdlFile, $originalClassName = '', $mockClassName = '', array $methods = [], $callOriginalConstructor = true, array $options = []) {
+  }
+}