Index: tests/phpunit/tests/http/http.php
===================================================================
--- tests/phpunit/tests/http/http.php	(revision 36294)
+++ tests/phpunit/tests/http/http.php	(working copy)
@@ -102,4 +102,17 @@
 		  - ://example.com - assumed path in PHP >= 5.4.7, fails in <5.4.7
 		*/
 	}
+
+	public function test_http_response_code_constants() {
+		global $wp_header_to_desc;
+
+		$ref = new ReflectionClass( 'WP_Http' );
+		$constants = $ref->getConstants();
+
+		// This primes the `$wp_header_to_desc` global:
+		get_status_header_desc( 200 );
+
+		$this->assertEquals( array_keys( $wp_header_to_desc ), array_values( $constants ) );
+
+	}
 }