diff --git a/core/modules/config/src/Tests/ConfigSchemaTestBase.php b/core/lib/Drupal/Core/Config/Schema/SchemaCheckTrait.php
similarity index 60%
rename from core/modules/config/src/Tests/ConfigSchemaTestBase.php
rename to core/lib/Drupal/Core/Config/Schema/SchemaCheckTrait.php
index eac1a75..06cabca 100644
--- a/core/modules/config/src/Tests/ConfigSchemaTestBase.php
+++ b/core/lib/Drupal/Core/Config/Schema/SchemaCheckTrait.php
@@ -2,26 +2,22 @@
 
 /**
  * @file
- * Contains Drupal\config\Tests\ConfigSchemaTestBase.
+ * Contains Drupal\Core\Config\Schema\SchemaCheckTrait.
  */
 
-namespace Drupal\config\Tests;
+namespace Drupal\Core\Config\Schema;
 
-use Drupal\Core\Config\Schema\ArrayElement;
 use Drupal\Core\Config\TypedConfigManagerInterface;
+use Drupal\Core\TypedData\PrimitiveInterface;
 use Drupal\Core\TypedData\Type\BooleanInterface;
 use Drupal\Core\TypedData\Type\StringInterface;
-use Drupal\Component\Utility\String;
-use Drupal\Core\Config\Schema\SchemaIncompleteException;
-use Drupal\Core\TypedData\PrimitiveInterface;
 use Drupal\Core\TypedData\Type\FloatInterface;
 use Drupal\Core\TypedData\Type\IntegerInterface;
-use Drupal\simpletest\WebTestBase;
 
 /**
- * Provides a base class to help test configuration schema.
+ * Provides a class for checking configuration schema.
  */
-abstract class ConfigSchemaTestBase extends WebTestBase {
+trait SchemaCheckTrait {
 
   /**
    * The config schema wrapper object for the configuration object under test.
@@ -38,14 +34,7 @@
   protected $configName;
 
   /**
-   * Global state for whether the config has a valid schema.
-   *
-   * @var boolean
-   */
-  protected $configPass;
-
-  /**
-   * Asserts the TypedConfigManager has a valid schema for the configuration.
+   * Checks the TypedConfigManager has a valid schema for the configuration.
    *
    * @param \Drupal\Core\Config\TypedConfigManagerInterface $typed_config
    *   The TypedConfigManager.
@@ -53,22 +42,25 @@
    *   The configuration name.
    * @param array $config_data
    *   The configuration data.
+   *
+   * @return array|FALSE|TRUE
+   *   False if no schema found. List of errors if any found. TRUE if fully
+   *   valid.
    */
-  public function assertConfigSchema(TypedConfigManagerInterface $typed_config, $config_name, $config_data) {
+  public function checkConfigSchema(TypedConfigManagerInterface $typed_config, $config_name, $config_data) {
     $this->configName = $config_name;
     if (!$typed_config->hasConfigSchema($config_name)) {
-      $this->fail(String::format('No schema for !config_name', array('!config_name' => $config_name)));
-      return;
+      return FALSE;
     }
     $definition = $typed_config->getDefinition($config_name);
     $this->schema = $typed_config->create($definition, $config_data);
-    $this->configPass = TRUE;
     foreach ($config_data as $key => $value) {
-      $this->checkValue($key, $value);
+      $errors = $this->checkValue($key, $value);
     }
-    if ($this->configPass) {
-      $this->pass(String::format('Schema found for !config_name and values comply with schema.', array('!config_name' => $config_name)));
+    if (empty($errors)) {
+      return TRUE;
     }
+    return $errors;
   }
 
   /**
@@ -79,25 +71,26 @@ public function assertConfigSchema(TypedConfigManagerInterface $typed_config, $c
    * @param mixed $value
    *   Value of given key.
    *
-   * @return mixed
-   *   Returns mixed value.
+   * @return array
+   *   List of errors found while checking with the corresponding schema.
    */
   protected function checkValue($key, $value) {
+    $error_key = $this->configName . ':' . $key;
     $element = FALSE;
     try {
       $element = $this->schema->get($key);
     }
     catch (SchemaIncompleteException $e) {
       if (is_scalar($value) || $value === NULL) {
-        $this->fail("{$this->configName}:$key has no schema.");
+        return array($error_key => 'Missing schema.');
       }
     }
     // Do not check value if it is defined to be ignored.
     if ($element && $element instanceof Ignore) {
-      return $value;
+      return array();
     }
 
-    if (is_scalar($value) || $value === NULL) {
+    if ($element && is_scalar($value) || $value === NULL) {
       $success = FALSE;
       $type = gettype($value);
       if ($element instanceof PrimitiveInterface) {
@@ -111,12 +104,13 @@ protected function checkValue($key, $value) {
       }
       $class = get_class($element);
       if (!$success) {
-        $this->fail("{$this->configName}:$key has the wrong schema. Variable type is $type and schema class is $class.");
+        return array($error_key => "Variable type is $type but applied schema class is $class.");
       }
     }
     else {
+      $errors = array();
       if (!$element instanceof ArrayElement) {
-        $this->fail("Non-scalar {$this->configName}:$key is not defined as an array type (such as mapping or sequence).");
+        $errors[$error_key] = 'Non-scalar value but not defined as an array (such as mapping or sequence)';
       }
 
       // Go on processing so we can get errors on all levels. Any non-scalar
@@ -126,18 +120,11 @@ protected function checkValue($key, $value) {
       }
       // Recurse into any nested keys.
       foreach ($value as $nested_value_key => $nested_value) {
-        $value[$nested_value_key] = $this->checkValue($key . '.' . $nested_value_key, $nested_value);
+        $errors = array_merge($errors, $this->checkValue($key . '.' . $nested_value_key, $nested_value));
       }
+      return $errors;
     }
-    return $value;
-  }
-
-  /**
-   * {@inheritdoc}
-   */
-  protected function fail($message = NULL, $group = 'Other') {
-    $this->configPass = FALSE;
-    return parent::fail($message, $group);
+    // No errors found.
+    return array();
   }
-
 }
diff --git a/core/modules/color/src/Tests/ColorConfigSchemaTest.php b/core/modules/color/src/Tests/ColorConfigSchemaTest.php
index ebaa303..bf7010c 100644
--- a/core/modules/color/src/Tests/ColorConfigSchemaTest.php
+++ b/core/modules/color/src/Tests/ColorConfigSchemaTest.php
@@ -7,12 +7,15 @@
 
 namespace Drupal\color\Tests;
 
-use Drupal\config\Tests\ConfigSchemaTestBase;
+use Drupal\config\Tests\SchemaCheckTestTrait;
+use Drupal\simpletest\WebTestBase;
 
 /**
  * Tests the Color config schema.
  */
-class ColorConfigSchemaTest extends ConfigSchemaTestBase {
+class ColorConfigSchemaTest extends WebTestBase {
+
+  use SchemaCheckTestTrait;
 
   /**
    * Modules to enable.
diff --git a/core/modules/config/src/Tests/DefaultConfigTest.php b/core/modules/config/src/Tests/DefaultConfigTest.php
index e90a058..04b697b 100644
--- a/core/modules/config/src/Tests/DefaultConfigTest.php
+++ b/core/modules/config/src/Tests/DefaultConfigTest.php
@@ -10,11 +10,14 @@
 use Drupal\config_test\TestInstallStorage;
 use Drupal\Core\Config\InstallStorage;
 use Drupal\Core\Config\TypedConfigManager;
+use Drupal\simpletest\WebTestBase;
 
 /**
  * Tests default configuration availability and type with configuration schema.
  */
-class DefaultConfigTest extends ConfigSchemaTestBase {
+class DefaultConfigTest extends WebTestBase {
+
+  use SchemaCheckTestTrait;
 
   /**
    * Modules to enable.
diff --git a/core/modules/config/src/Tests/SchemaCheckTestTrait.php b/core/modules/config/src/Tests/SchemaCheckTestTrait.php
new file mode 100644
index 0000000..64358b5
--- /dev/null
+++ b/core/modules/config/src/Tests/SchemaCheckTestTrait.php
@@ -0,0 +1,52 @@
+<?php
+
+/**
+ * @file
+ * Contains Drupal\config\Tests\SchemaCheckTestTrait.
+ */
+
+namespace Drupal\config\Tests;
+
+use Drupal\Core\Config\TypedConfigManagerInterface;
+use Drupal\Core\Config\Schema\SchemaCheckTrait;
+use Drupal\Component\Utility\String;
+
+/**
+ * Provides a class for checking configuration schema.
+ */
+trait SchemaCheckTestTrait {
+
+  use SchemaCheckTrait;
+
+  /**
+   * Asserts the TypedConfigManager has a valid schema for the configuration.
+   *
+   * @param \Drupal\Core\Config\TypedConfigManagerInterface $typed_config
+   *   The TypedConfigManager.
+   * @param string $config_name
+   *   The configuration name.
+   * @param array $config_data
+   *   The configuration data.
+   */
+  public function assertConfigSchema(TypedConfigManagerInterface $typed_config, $config_name, $config_data) {
+    $errors = $this->checkConfigSchema($typed_config, $config_name, $config_data);
+    if ($errors === FALSE) {
+      //@TODO: Since the use of this trait is under TestBase, it works.
+      // Can be fixed as part of https://drupal.org/node/2260053.
+      $this->fail(String::format('No schema for !config_name', array('!config_name' => $config_name)));
+      return;
+    }
+    elseif ($errors === TRUE) {
+      //@TODO: Since the use of this trait is under TestBase, it works.
+      // Can be fixed as part of https://drupal.org/node/2260053.
+      $this->pass(String::format('Schema found for !config_name and values comply with schema.', array('!config_name' => $config_name)));
+    }
+    else {
+      foreach ($errors as $key => $error) {
+        //@TODO: Since the use of this trait is under TestBase, it works.
+        // Can be fixed as part of https://drupal.org/node/2260053.
+        $this->fail($key . ': ' . $error);
+      }
+    }
+  }
+}
diff --git a/core/modules/language/src/Tests/LanguageConfigSchemaTest.php b/core/modules/language/src/Tests/LanguageConfigSchemaTest.php
index 57ed784..35e207a 100644
--- a/core/modules/language/src/Tests/LanguageConfigSchemaTest.php
+++ b/core/modules/language/src/Tests/LanguageConfigSchemaTest.php
@@ -7,12 +7,15 @@
 
 namespace Drupal\language\Tests;
 
-use Drupal\config\Tests\ConfigSchemaTestBase;
+use Drupal\config\Tests\SchemaCheckTestTrait;
+use Drupal\simpletest\WebTestBase;
 
 /**
  * Tests the language config schema.
  */
-class LanguageConfigSchemaTest extends ConfigSchemaTestBase {
+class LanguageConfigSchemaTest extends WebTestBase {
+
+  use SchemaCheckTestTrait;
 
   /**
    * Modules to enable.
diff --git a/core/modules/user/src/Tests/UserActionConfigSchemaTest.php b/core/modules/user/src/Tests/UserActionConfigSchemaTest.php
index 3e616d5..08d88a1 100644
--- a/core/modules/user/src/Tests/UserActionConfigSchemaTest.php
+++ b/core/modules/user/src/Tests/UserActionConfigSchemaTest.php
@@ -7,12 +7,15 @@
 
 namespace Drupal\user\Tests;
 
-use Drupal\config\Tests\ConfigSchemaTestBase;
+use Drupal\config\Tests\SchemaCheckTestTrait;
+use Drupal\simpletest\WebTestBase;
 
 /**
  * Tests the User action config schema.
  */
-class UserActionConfigSchemaTest extends ConfigSchemaTestBase {
+class UserActionConfigSchemaTest extends WebTestBase {
+
+  use SchemaCheckTestTrait;
 
   /**
    * Modules to enable.