diff --git a/.gitignore b/.gitignore
index a79486f..3f9053a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 vendor
 composer.lock
 phpunit.xml
+.phpunit.result.cache
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index 9c251d1..5d2f6f3 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -1,6 +1,13 @@
 <?xml version="1.0" encoding="UTF-8"?>
-
-<phpunit colors="true" bootstrap="vendor/autoload.php">
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xsi:noNamespaceSchemaLocation="vendor/phpunit/phpunit/phpunit.xsd"
+    colors="true"
+    bootstrap="vendor/autoload.php"
+    convertErrorsToExceptions="true"
+    convertWarningsToExceptions="true"
+    convertNoticesToExceptions="true"
+    convertDeprecationsToExceptions="true"
+    >
     <testsuites>
         <testsuite name="Prophecy PhpUnit Test Suite">
             <directory suffix="Test.php">./tests/</directory>