diff --git a/.travis.yml b/.travis.yml
index 82d9ff4b..56371df2 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -33,7 +33,10 @@ before_install:
   - if [[ $COVERAGE != yes ]]; then phpenv config-rm xdebug.ini || true; fi;
 
 install:
-  - composer update --prefer-dist --no-interaction
+  - if [[ $TRAVIS_PHP_VERSION = hhvm-3.30 ]]; then composer require phpunit/phpunit:4.8.36 --dev; fi
+  - export COMPOSER_FLAGS="--prefer-dist --no-interaction"
+  - if [[ $TRAVIS_PHP_VERSION = nightly ]]; then export COMPOSER_FLAGS="$COMOPSER_FLAGS --ignore-platform-reqs"; fi
+  - composer update $COMPOSER_FLAGS
 
 script:
   - if [[ $COVERAGE = yes ]]; then vendor/bin/phpunit --coverage-clover=coverage.clover; else vendor/bin/phpunit; fi
diff --git a/composer.json b/composer.json
index b6002ef3..1aa9f270 100644
--- a/composer.json
+++ b/composer.json
@@ -18,8 +18,7 @@
         "symfony/polyfill-ctype": "^1.8"
     },
     "require-dev": {
-        "phpunit/phpunit": "^4.6",
-        "sebastian/version": "^1.0.1"
+        "phpunit/phpunit": "^4.8.36 || ^7.5.13"
     },
     "extra": {
         "branch-alias": {
diff --git a/tests/AssertTest.php b/tests/AssertTest.php
index fe675337..69543082 100644
--- a/tests/AssertTest.php
+++ b/tests/AssertTest.php
@@ -16,7 +16,6 @@
 use Exception;
 use Error;
 use LogicException;
-use PHPUnit_Framework_TestCase;
 use RuntimeException;
 use stdClass;
 use Webmozart\Assert\Assert;
@@ -26,7 +25,7 @@
  *
  * @author Bernhard Schussek <bschussek@gmail.com>
  */
-class AssertTest extends PHPUnit_Framework_TestCase
+class AssertTest extends BaseTestCase
 {
     private static $resource;
 
@@ -359,7 +358,7 @@ public function getTests()
             // no tests for readable()/writable() for now
             array('classExists', array(__CLASS__), true),
             array('classExists', array(__NAMESPACE__.'\Foobar'), false),
-            array('subclassOf', array(__CLASS__, 'PHPUnit_Framework_TestCase'), true),
+            array('subclassOf', array(__CLASS__, 'Webmozart\Assert\Tests\BaseTestCase'), true),
             array('subclassOf', array(__CLASS__, 'stdClass'), false),
             array('interfaceExists', array('\Countable'), true),
             array('interfaceExists', array(__CLASS__), false),
@@ -506,6 +505,7 @@ public function testAssert($method, $args, $success, $multibyte = false, $minVer
         }
 
         call_user_func_array(array('Webmozart\Assert\Assert', $method), $args);
+        $this->addToAssertionCount(1);
     }
 
     /**
@@ -527,6 +527,7 @@ public function testNullOr($method, $args, $success, $multibyte = false, $minVer
         }
 
         call_user_func_array(array('Webmozart\Assert\Assert', 'nullOr'.ucfirst($method)), $args);
+        $this->addToAssertionCount(1);
     }
 
     /**
@@ -535,6 +536,7 @@ public function testNullOr($method, $args, $success, $multibyte = false, $minVer
     public function testNullOrAcceptsNull($method)
     {
         call_user_func(array('Webmozart\Assert\Assert', 'nullOr'.ucfirst($method)), null);
+        $this->addToAssertionCount(1);
     }
 
     /**
@@ -559,6 +561,7 @@ public function testAllArray($method, $args, $success, $multibyte = false, $minV
         array_unshift($args, array($arg));
 
         call_user_func_array(array('Webmozart\Assert\Assert', 'all'.ucfirst($method)), $args);
+        $this->addToAssertionCount(1);
     }
 
     /**
@@ -583,6 +586,7 @@ public function testAllTraversable($method, $args, $success, $multibyte = false,
         array_unshift($args, new ArrayIterator(array($arg)));
 
         call_user_func_array(array('Webmozart\Assert\Assert', 'all'.ucfirst($method)), $args);
+        $this->addToAssertionCount(1);
     }
 
     public function getStringConversions()
diff --git a/tests/BaseTestCase.php b/tests/BaseTestCase.php
new file mode 100644
index 00000000..c48b10d0
--- /dev/null
+++ b/tests/BaseTestCase.php
@@ -0,0 +1,36 @@
+<?php
+
+namespace Webmozart\Assert\Tests;
+
+use PHPUnit\Framework\TestCase;
+
+/**
+ * This class allows us to be compatible with multiple PHPUnit versions.
+ */
+class BaseTestCase extends TestCase
+{
+    /**
+     * The setExpectedException got removed in later phpunit versions,
+     * and instead it got split up into three functions.
+     *
+     * So if the newer functions exist we call those where needed, and otherwise
+     * we just use the original function.
+     *
+     * @param string $exceptionName
+     * @param string $exceptionMessage
+     * @param int $exceptionCode
+     */
+    public function setExpectedException($exceptionName, $exceptionMessage = '', $exceptionCode = null) {
+        if (method_exists($this, 'expectException')) {
+            $this->expectException($exceptionName);
+            if($exceptionMessage) {
+                $this->expectExceptionMessage($exceptionMessage);
+            }
+            if( $exceptionCode) {
+                $this->expectExceptionCode($exceptionCode);
+            }
+            return;
+        }
+        parent::setExpectedException($exceptionName, $exceptionMessage, $exceptionCode);
+    }
+}
diff --git a/tests/ProjectCodeTest.php b/tests/ProjectCodeTest.php
index e8731572..bce516c7 100644
--- a/tests/ProjectCodeTest.php
+++ b/tests/ProjectCodeTest.php
@@ -2,14 +2,13 @@
 
 namespace Webmozart\Assert\Tests;
 
-use PHPUnit_Framework_TestCase;
 use ReflectionClass;
 use ReflectionMethod;
 
 /**
  * @coversNothing
  */
-class ProjectCodeTest extends PHPUnit_Framework_TestCase
+class ProjectCodeTest extends BaseTestCase
 {
     private static $readmeContent;
     private static $assertDocComment;