diff --git a/tests/phpunit/tests/formatting/CleanPre.php b/tests/phpunit/tests/formatting/CleanPre.php
index fb5eea90df..410b5095f8 100644
--- a/tests/phpunit/tests/formatting/CleanPre.php
+++ b/tests/phpunit/tests/formatting/CleanPre.php
@@ -7,6 +7,26 @@
  * @group formatting
  */
 class Tests_Formatting_CleanPre extends WP_UnitTestCase {
+	function setUp() {
+		parent::setUp();
+		add_action( 'deprecated_function_run', array( $this, 'deprecated_function_run_check' ) );
+	}
+
+	function tearDown() {
+		parent::tearDown();
+		remove_action( 'deprecated_function_run', array( $this, 'deprecated_function_run_check' ) );
+	}
+
+	function deprecated_function_run_check( $function ) {
+		if ( in_array( $function, array( 'clean_pre' ) ) )
+			add_filter( 'deprecated_function_trigger_error', array( $this, 'deprecated_function_trigger_error' ) );
+	}
+
+	function deprecated_function_trigger_error() {
+		remove_filter( 'deprecated_function_trigger_error', array( $this, 'deprecated_function_trigger_error' ) );
+		return false;
+	}
+
 	function test_removes_self_closing_br_with_space() {
 		$source = 'a b c\n<br />sldfj<br />';
 		$res = 'a b c\nsldfj';