diff --git a/core/composer.json b/core/composer.json
index 26938e3..6d13411 100644
--- a/core/composer.json
+++ b/core/composer.json
@@ -34,7 +34,8 @@
     "fabpot/goutte": "~3.1",
     "masterminds/html5": "~2.1",
     "symfony/psr-http-message-bridge": "v0.2",
-    "zendframework/zend-diactoros": "1.1.0"
+    "zendframework/zend-diactoros": "1.1.0",
+    "aki-tendo/php7exception": "1.0.1"
   },
   "replace": {
     "drupal/action": "self.version",
diff --git a/core/composer.lock b/core/composer.lock
index 676d0bf..93f0f24 100644
--- a/core/composer.lock
+++ b/core/composer.lock
@@ -4,9 +4,48 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#composer-lock-the-lock-file",
         "This file is @generated automatically"
     ],
-    "hash": "3708d8fdb54957e5ce661cda1df88353",
+    "hash": "96cbee9491e5a700b62ad8095c1676ef",
     "packages": [
         {
+            "name": "aki-tendo/php7exception",
+            "version": "1.0.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/TendoAki/php-7-exceptions-in-php-5.git",
+                "reference": "f7f68905fddc58f452de4e3d11120f694045bb52"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/TendoAki/php-7-exceptions-in-php-5/zipball/f7f68905fddc58f452de4e3d11120f694045bb52",
+                "reference": "f7f68905fddc58f452de4e3d11120f694045bb52",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.3.0"
+            },
+            "type": "library",
+            "autoload": {
+                "files": [
+                    "php7exceptions.php"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Michael Lloyd Morris",
+                    "email": "tendoAki@gmail.com",
+                    "homepage": "https://github.com/TendoAki/",
+                    "role": "developer"
+                }
+            ],
+            "description": "Configures PHP 5.x to throw PHP 7 exceptions when possible",
+            "homepage": "https://github.com/TendoAki/php-7-exceptions-in-php-5",
+            "time": "2015-07-22 18:04:37"
+        },
+        {
             "name": "behat/mink",
             "version": "v1.6.1",
             "source": {
diff --git a/core/core.api.php b/core/core.api.php
index de34440..e9a6733 100644
--- a/core/core.api.php
+++ b/core/core.api.php
@@ -1000,7 +1000,7 @@
  * verified with standard control structures at all times, not just checked in
  * development environments with assert() statements on.
  *
- * When runtime assertions fail in PHP 7 an \AssertionException is thrown.
+ * When runtime assertions fail in PHP 7 an \AssertionError is thrown.
  * Drupal uses an assertion callback to do the same in PHP 5.x so that unit
  * tests involving runtime assertions will work uniformly across both versions.
  *
diff --git a/core/vendor/aki-tendo/php7exception/LICENSE b/core/vendor/aki-tendo/php7exception/LICENSE
new file mode 100644
index 0000000..df564ad
--- /dev/null
+++ b/core/vendor/aki-tendo/php7exception/LICENSE
@@ -0,0 +1,21 @@
+                            The MIT License (MIT)
+
+                  Copyright (c) 2015 Michael Lloyd Morris
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
diff --git a/core/vendor/aki-tendo/php7exception/README.md b/core/vendor/aki-tendo/php7exception/README.md
new file mode 100644
index 0000000..a9321f1
--- /dev/null
+++ b/core/vendor/aki-tendo/php7exception/README.md
@@ -0,0 +1,14 @@
+# php-7-exceptions-in-php-5
+
+PHP 7 can throw exceptions in many situations where PHP 5.x uses errors.
+This can make writing unit tests that pass both versions something of a
+headache. The goal of this package is to alleviate this headache.
+
+This is version 1.0 and only addresses assert() statement failures by using
+the assert callback to throw an AssertionError when such a statement fails.
+This allows a PHPUnit test to use the annotation "@expectedException
+AssertionError" to check the assertion and not worry about whether the test
+is running under PHP 5.x or 7.
+
+Subsequent versions of this package will deal with other error types, starting
+with the various errors in group E_RECOVERABLE_ERROR.
diff --git a/core/vendor/aki-tendo/php7exception/composer.json b/core/vendor/aki-tendo/php7exception/composer.json
new file mode 100644
index 0000000..71e1c36
--- /dev/null
+++ b/core/vendor/aki-tendo/php7exception/composer.json
@@ -0,0 +1,22 @@
+{
+    "name": "aki-tendo/php7exception",
+    "description": "Configures PHP 5.x to throw PHP 7 exceptions when possible",
+    "homepage": "https://github.com/TendoAki/php-7-exceptions-in-php-5",
+    "license": "MIT",
+    "authors": [
+      {
+        "name": "Michael Lloyd Morris",
+        "email": "tendoAki@gmail.com",
+        "homepage": "https://github.com/TendoAki/",
+        "role": "developer"
+      }
+    ],
+    "require": {
+        "php": ">=5.3.0"
+    },
+    "autoload": {
+      "files": [
+        "php7exceptions.php"
+      ]
+    }
+}
diff --git a/core/vendor/aki-tendo/php7exception/php7exceptions.php b/core/vendor/aki-tendo/php7exception/php7exceptions.php
new file mode 100644
index 0000000..ef87966
--- /dev/null
+++ b/core/vendor/aki-tendo/php7exception/php7exceptions.php
@@ -0,0 +1,34 @@
+<?php
+
+/**
+ * @file
+ * Force PHP 5.x to behave as PHP 7 does as much as possible.
+ *
+ * PHP 7 can throw exceptions in many situations where PHP 5.x uses errors.
+ * This can make writing tests that pass both versions something of a headache.
+ * The situation can be eased some by using the callbacks provided by the PHP
+ * engine. It cannot cover all of the possible use cases, but it should be
+ * able to handle a majority by allowing unit test authors to use the same
+ * expectedException annotation regardless of the version of PHP they run.
+ * Unfortunately the error message string will likely be different between
+ * versions.
+ *
+ * This first version of the package deals with the simplest use case -
+ * AssertionErrors.
+ *
+ * @package aki-tendo/php7exception
+ * @author Michael Lloyd Morris
+ */
+
+if (version_compare(PHP_VERSION, '7.0.0-dev') === -1) {
+  class AssertionError extends Exception {}
+
+  // Assertions throws.
+  assert_options(ASSERT_CALLBACK, function($file, $line, $code, $message = '') {
+    if (empty($message)) {
+      $message = "Assertion Failure in {$file} at {$line}. Failed asserting {$code}";
+    }
+    throw new AssertionError($message);
+  });
+}
+
diff --git a/core/vendor/aki-tendo/php7exception/tests/AssertionErrorTest.php b/core/vendor/aki-tendo/php7exception/tests/AssertionErrorTest.php
new file mode 100644
index 0000000..4138c0d
--- /dev/null
+++ b/core/vendor/aki-tendo/php7exception/tests/AssertionErrorTest.php
@@ -0,0 +1,23 @@
+<?php
+/**
+ * @file
+ * Contains \AssertionErrorTest.
+ *
+ * @package aki-tendo/php7exception
+ * @author Michael Lloyd Morris
+ */
+
+require_once '../php7exceptions.php';
+assert_options(ASSERT_ACTIVE, 1);
+
+/**
+ * Tests assertion error conversion to correct PHP 7 exception class.
+ */
+class AssertionErrorTest extends PHPUnit_Framework_TestCase {
+  /**
+   * @expectedException AssertionError
+   */
+  public function testAssertErrorThrow() {
+    assert(false);
+  }
+}
diff --git a/core/vendor/composer/autoload_files.php b/core/vendor/composer/autoload_files.php
index 6f932aa..79f3e25 100644
--- a/core/vendor/composer/autoload_files.php
+++ b/core/vendor/composer/autoload_files.php
@@ -9,5 +9,6 @@
     $vendorDir . '/guzzlehttp/psr7/src/functions.php',
     $vendorDir . '/guzzlehttp/promises/src/functions.php',
     $vendorDir . '/guzzlehttp/guzzle/src/functions_include.php',
+    $vendorDir . '/aki-tendo/php7exception/php7exceptions.php',
     $baseDir . '/lib/Drupal.php',
 );
diff --git a/core/vendor/composer/installed.json b/core/vendor/composer/installed.json
index e063543..3764118 100644
--- a/core/vendor/composer/installed.json
+++ b/core/vendor/composer/installed.json
@@ -3477,5 +3477,46 @@
             "validation",
             "validator"
         ]
+    },
+    {
+        "name": "aki-tendo/php7exception",
+        "version": "1.0.1",
+        "version_normalized": "1.0.1.0",
+        "source": {
+            "type": "git",
+            "url": "https://github.com/TendoAki/php-7-exceptions-in-php-5.git",
+            "reference": "f7f68905fddc58f452de4e3d11120f694045bb52"
+        },
+        "dist": {
+            "type": "zip",
+            "url": "https://api.github.com/repos/TendoAki/php-7-exceptions-in-php-5/zipball/f7f68905fddc58f452de4e3d11120f694045bb52",
+            "reference": "f7f68905fddc58f452de4e3d11120f694045bb52",
+            "shasum": ""
+        },
+        "require": {
+            "php": ">=5.3.0"
+        },
+        "time": "2015-07-22 18:04:37",
+        "type": "library",
+        "installation-source": "dist",
+        "autoload": {
+            "files": [
+                "php7exceptions.php"
+            ]
+        },
+        "notification-url": "https://packagist.org/downloads/",
+        "license": [
+            "MIT"
+        ],
+        "authors": [
+            {
+                "name": "Michael Lloyd Morris",
+                "email": "tendoAki@gmail.com",
+                "homepage": "https://github.com/TendoAki/",
+                "role": "developer"
+            }
+        ],
+        "description": "Configures PHP 5.x to throw PHP 7 exceptions when possible",
+        "homepage": "https://github.com/TendoAki/php-7-exceptions-in-php-5"
     }
 ]