diff --git a/ctools.info b/ctools.info
index 0bced99..93466d2 100644
--- a/ctools.info
+++ b/ctools.info
@@ -15,3 +15,7 @@ files[] = tests/ctools.plugins.test
 files[] = tests/math_expression.test
 files[] = tests/math_expression_stack.test
 files[] = tests/object_cache.test
+files[] = tests/object_cache_unit.test
+files[] = tests/page_tokens.test
+files[] = tests/uuid_with_uuid.test
+files[] = tests/uuid_without_uuid.test
diff --git a/ctools.module b/ctools.module
index 78ac26b..c7bd80a 100644
--- a/ctools.module
+++ b/ctools.module
@@ -314,23 +314,29 @@ function ctools_break_phrase($str) {
  * Set a token/value pair to be replaced later in the request, specifically in
  * ctools_page_token_processing().
  *
- * @param $token
+ * @param string $token
  *   The token to be replaced later, during page rendering.  This should
- *    ideally be a string inside of an HTML comment, so that if there is
- *    no replacement, the token will not render on the page.
- * @param $type
+ *   ideally be a string inside of an HTML comment, so that if there is
+ *   no replacement, the token will not render on the page.
+ *   If $token is NULL, the token set is not changed, but is still
+ *   returned.
+ * @param string $type
  *   The type of the token. Can be either 'variable', which will pull data
- *   directly from the page variables
- * @param $argument
- *   If $type == 'variable' then argument should be the key to fetch from
- *   the $variables. If $type == 'callback' then it should either be the
- *   callback, or an array that will be sent to call_user_func_array().
+ *   directly from the page variables, or 'callback', which causes a function
+ *   to be called to calculate the value. No other values are supported.
+ * @param string|array $argument
+ *   For $type of:
+ *   - 'variable': argument should be the key to fetch from the $variables.
+ *   - 'callback': then it should either be the callback function name as a
+ *     string, or an array that will be sent to call_user_func_array(). Argument
+ *     arrays must not use array keys (i.e. $a[0] is the first and $a[1] the
+ *     second element, etc.)
  *
- * @return
+ * @return array
  *   A array of token/variable names to be replaced.
  */
 function ctools_set_page_token($token = NULL, $type = NULL, $argument = NULL) {
-  static $tokens = array();
+  $tokens = &drupal_static('ctools_set_page_token', array());
 
   if (isset($token)) {
     $tokens[$token] = array($type, $argument);
@@ -339,13 +345,32 @@ function ctools_set_page_token($token = NULL, $type = NULL, $argument = NULL) {
 }
 
 /**
- * Easily set a token from the page variables.
+ * Reset the defined page tokens within this request.
+ *
+ * Introduced for simpletest purposes. Normally not needed.
+ */
+function ctools_reset_page_tokens() {
+  drupal_static_reset('ctools_set_page_token');
+}
+
+/**
+ * Set a replacement token from the containing element's children during #post_render.
  *
  * This function can be used like this:
- * $token = ctools_set_variable_token('tabs');
+ *   $token = ctools_set_variable_token('tabs');
  *
- * $token will then be a simple replacement for the 'tabs' about of the
- * variables available in the page template.
+ * The token "<!-- ctools-page-tabs -->" would then be replaced by the value of
+ * this element's (sibling) render array key 'tabs' during post-render (or be
+ * deleted if there was no such key by that point).
+ *
+ * @param string $token
+ *   The token string for the page callback, e.g. 'title'
+ *
+ * @return string
+ *   The constructed token.
+ *
+ * @see ctools_set_callback_token().
+ * @see ctools_page_token_processing().
  */
 function ctools_set_variable_token($token) {
   $string = '<!-- ctools-page-' . $token . ' -->';
@@ -354,10 +379,45 @@ function ctools_set_variable_token($token) {
 }
 
 /**
- * Easily set a token from the page variables.
+ * Set a replacement token from the value of a function during #post_render.
  *
  * This function can be used like this:
- * $token = ctools_set_variable_token('id', 'mymodule_myfunction');
+ *   $token = ctools_set_callback_token('id', 'mymodule_myfunction');
+ *
+ * Or this (from its use in ctools_page_title_content_type_render):
+ *   $token = ctools_set_callback_token('title', array(
+ *       'ctools_page_title_content_type_token', $conf['markup'], $conf['id'], $conf['class']
+ *     )
+ *   );
+ *
+ * The token (e.g: "<!-- ctools-page-id-1b7f84d1c8851290cc342631ac663053 -->")
+ * would then be replaced during post-render by the return value of:
+ *
+ *   ctools_page_title_content_type_token($value_markup, $value_id, $value_class);
+ *
+ * @param string $token
+ *   The token string for the page callback, e.g. 'title'
+ *
+ * @param string|array $callback
+ *   For callback functions that require no args, the name of the function as a
+ *   string; otherwise an array of two or more elements: the function name
+ *   followed by one or more function arguments.
+ *
+ *   NB: the value of $callback must be a procedural (non-class) function that
+ *   passes the php function_exists() check.
+ *
+ *   The callback function itself will be called with args dependent
+ *   on $callback. If:
+ *    - $callback is a string, the function is called with a reference to the
+ *      render array;
+ *    - $callback is an array, the function is called with $callback merged
+ *      with an array containing a reference to the render array.
+ *
+ * @return string
+ *   The constructed token.
+ *
+ * @see ctools_set_variable_token().
+ * @see ctools_page_token_processing().
  */
 function ctools_set_callback_token($token, $callback) {
   // If the callback uses arguments they are considered in the token.
diff --git a/tests/context.test b/tests/context.test
index 2dd4f4d..92f9cd1 100644
--- a/tests/context.test
+++ b/tests/context.test
@@ -1,6 +1,13 @@
 <?php
 
+/**
+ * Test the keyword substitution functionality.
+ */
 class CtoolsContextKeywordsSubstitutionTestCase extends DrupalWebTestCase {
+
+  /**
+   * {@inheritDoc}
+   */
   public static function getInfo() {
     return array(
       'name' => 'Keywords substitution',
@@ -9,12 +16,19 @@ public static function getInfo() {
     );
   }
 
-  public function setUp() {
-    parent::setUp('ctools');
+  /**
+   * {@inheritDoc}
+   */
+  function setUp(array $modules = array()) {
+    $modules[] = 'ctools';
+    parent::setUp($modules);
 
     ctools_include('context');
   }
 
+  /**
+   * Test the keyword substitution.
+   */
   public function testKeywordsSubstitution() {
     // Create node context for substitution.
     $node = $this->drupalCreateNode();
diff --git a/tests/css.test b/tests/css.test
index 3ffd42a..aaef842 100644
--- a/tests/css.test
+++ b/tests/css.test
@@ -1,13 +1,13 @@
 <?php
-/**
- * @file
- * Tests for different parts of the ctools plugin system.
- */
 
 /**
  * Test menu links depending on user permissions.
  */
 class CtoolsCssTestCase extends DrupalWebTestCase {
+
+  /**
+   * {@inheritDoc}
+   */
   public static function getInfo() {
     return array(
       'name' => 'CSS Tools tests',
@@ -16,50 +16,87 @@ public static function getInfo() {
     );
   }
 
-  function setUp() {
-    // Additionally enable contact module.
-    parent::setUp('ctools');
+  /**
+   * {@inheritDoc}
+   */
+  function setUp(array $modules = array()) {
+    $modules[] = 'ctools';
+    parent::setUp($modules);
+    ctools_include('css');
   }
 
   /**
-   * Test that cached plugins are loaded correctly.
+   * Test that Stored CSS snippets can be retrieved, filtered or otherwise.
    */
-  function testCssStuff() {
+  public function testCssStoreFilterRetrieve() {
     $css = "#some-id .some-class {\n  color: black;\n  illegal-key: foo;\n}";
     $filtered_css = '#some-id .some-class{color:black;}';
 
-    ctools_include('css');
+    $this->assertNull(ctools_css_retrieve('missing-css-test'), 'Missing css snippet is not found');
+
     $filename1 = ctools_css_store('unfiltered-css-test', $css, FALSE);
     $filename2 = ctools_css_store('filtered-css-test', $css, TRUE);
 
+    $file_contents = file_get_contents($filename1);
+    $this->assertEqual($css, $file_contents, 'Unfiltered css file contents are correct');
+
     $this->assertEqual($filename1, ctools_css_retrieve('unfiltered-css-test'), 'Unfiltered css file successfully fetched');
     $file_contents = file_get_contents($filename1);
     $this->assertEqual($css, $file_contents, 'Unfiltered css file contents are correct');
-//    $match = $filename1 == ctools_css_retrieve('unfiltered-css-test') ? 'Match' : 'No match';
-//    $output .= '<pre>Unfiltered: ' . $filename1 . ' ' . $match . '</pre>';
-//    $output .= '<pre>' . file_get_contents($filename1) . '</pre>';
 
     $this->assertEqual($filename2, ctools_css_retrieve('filtered-css-test'), 'Filtered css file succcesfully fetched');
     $file_contents = file_get_contents($filename2);
     $this->assertEqual($filtered_css, $file_contents, 'Filtered css file contents are correct');
-    //    $match = $filename2 == ctools_css_retrieve('filtered-css-test') ? 'Match' : 'No match';
-//    $output .= '<pre>Filtered: ' . $filename2 . ' ' . $match . '</pre>';
-//    $output .= '<pre>' . file_get_contents($filename2) . '</pre>';
-//
-//    drupal_add_css($filename2, array('type' => 'file'));
-//    return array('#markup' => $output);
+  }
 
+  /**
+   * @todo Test  db-row-exist but file-not-exist case in ctools_css_retrieve().
+   */
 
-    // Test that in case that url can be used, the value surives when a colon is in it.
+  /**
+   * Test that Stored CSS snippets can be correctly overwritten.
+   */
+  public function testCssStoreOverwrite() {
+    $css1 = "#some-id .some-class {\n  color: black;\n  illegal-key: foo;\n}";
+
+    $css2 = "#other-id .other-class {\n  color: blue;\n  illegal-key: foo;\n}";
+    $filtered_css2 = '#other-id .other-class{color:blue;}';
+
+    ctools_css_store('unfiltered-css-test', $css1, FALSE);
+    ctools_css_store('filtered-css-test', $css1, TRUE);
+
+    // Now overwrite the first css with the second version.
+
+    $filename3 = ctools_css_store('unfiltered-css-test', $css2, FALSE);
+    $filename4 = ctools_css_store('filtered-css-test', $css2, TRUE);
+
+    $file_contents3 = file_get_contents($filename3);
+    $file_contents4 = file_get_contents($filename4);
+
+    $this->assertEqual($css2, $file_contents3, 'Unfiltered CSS has overwritten earlier contents.');
+    $this->assertEqual($filtered_css2, $file_contents4, 'Filtered CSS has overwritten earlier contents.');
+  }
+
+  /**
+   * Test that in case that url is used, the colons survives filtering.
+   */
+  public function testCssFilterURLHandling() {
     $css = "#some-id {\n  background-image: url(http://example.com/example.gif);\n}";
     $css_data = ctools_css_disassemble($css);
     $empty_array = array();
     $disallowed_values_regex = '/(expression)/';
-    $filtered = ctools_css_assemble(ctools_css_filter_css_data($css_data, $empty_array, $empty_array, '', $disallowed_values_regex));
+
+    $intermediate = ctools_css_filter_css_data($css_data, $empty_array, $empty_array, '', $disallowed_values_regex);
+    $filtered = ctools_css_assemble($intermediate);
+
     $url = (strpos($filtered, 'http://example.com/example.gif') !== FALSE);
     $this->assertTrue($url, 'CSS with multiple colons can survive.');
+  }
 
-    // Test that in case the CSS has two properties defined are merged.
+  /**
+   * Test that when the CSS has two properties defined they are merged.
+   */
+  public function testCssFilterMergeProperties() {
     $css = "#some-id {\n  font-size: 12px;\n}\n#some-id {\n  color: blue;\n}";
     $filtered = ctools_css_filter($css);
     $font_size = (strpos($filtered, 'font-size:12px;') !== FALSE);
@@ -78,4 +115,5 @@ function testCssStuff() {
     $color = (strpos($filtered, 'color:red') !== FALSE);
     $this->assertTrue($font_size && $color, 'Multiple properties are retained.');
   }
+
 }
diff --git a/tests/css_cache.test b/tests/css_cache.test
index 0b3528d..26ae68e 100644
--- a/tests/css_cache.test
+++ b/tests/css_cache.test
@@ -1,13 +1,9 @@
 <?php
-/**
- * @file
- * Tests the custom CSS cache handler.
- */
 
 /**
  * Tests the custom CSS cache handler.
  */
-class CtoolsObjectCache extends DrupalWebTestCase {
+class CtoolsCSSObjectCache extends DrupalWebTestCase {
 
   /**
    * {@inheritdoc}
@@ -21,10 +17,11 @@ public static function getInfo() {
   }
 
   /**
-   * {@inheritdoc}
+   * {@inheritDoc}
    */
-  public function setUp() {
-    parent::setUp('ctools');
+  function setUp(array $modules = array()) {
+    $modules[] = 'ctools';
+    parent::setUp($modules);
   }
 
   /**
diff --git a/tests/ctools.plugins.test b/tests/ctools.plugins.test
index 7e866b1..e0f317f 100644
--- a/tests/ctools.plugins.test
+++ b/tests/ctools.plugins.test
@@ -1,13 +1,13 @@
 <?php
-/**
- * @file
- * Tests for different parts of the ctools plugin system.
- */
 
 /**
  * Test menu links depending on user permissions.
  */
 class CtoolsPluginsGetInfoTestCase extends DrupalWebTestCase {
+
+  /**
+   * {@inheritDoc}
+   */
   public static function getInfo() {
     return array(
       'name' => 'Get plugin info',
@@ -16,11 +16,23 @@ public static function getInfo() {
     );
   }
 
-  function setUp() {
-    // Additionally enable contact module.
-    parent::setUp('ctools', 'ctools_plugin_test');
+  /**
+   * {@inheritDoc}
+   */
+  function setUp(array $modules = array()) {
+    $modules[] = 'ctools';
+    $modules[] = 'ctools_plugin_test';
+    parent::setUp($modules);
   }
 
+  /**
+   *
+   *
+   * @param string $module
+   * @param string $type
+   * @param mixed $id
+   * @param string $function
+   */
   protected function assertPluginFunction($module, $type, $id, $function = 'function') {
     $func = ctools_plugin_load_function($module, $type, $id, $function);
     $this->assertTrue(function_exists($func), t('Plugin @plugin of plugin type @module:@type successfully retrieved @retrieved for @function.', array(
@@ -32,6 +44,14 @@ protected function assertPluginFunction($module, $type, $id, $function = 'functi
     )));
   }
 
+  /**
+   *
+   *
+   * @param string $module
+   * @param string $type
+   * @param mixed $id
+   * @param string $function
+   */
   protected function assertPluginMissingFunction($module, $type, $id, $function = 'function') {
     $func = ctools_plugin_load_function($module, $type, $id, $function);
     $this->assertEqual($func, NULL, t('Plugin @plugin of plugin type @module:@type for @function with missing function successfully failed.', array(
@@ -53,6 +73,14 @@ protected function assertPluginClass($module, $type, $id, $class = 'handler') {
     )));
   }
 
+  /**
+   *
+   *
+   * @param string $module
+   * @param string $type
+   * @param mixed $id
+   * @param string $function
+   */
   protected function assertPluginMissingClass($module, $type, $id, $class = 'handler') {
     $class_name = ctools_plugin_load_class($module, $type, $id, $class);
     $this->assertEqual($class_name, NULL, t('Plugin @plugin of plugin type @module:@type for @class with missing class successfully failed.', array(
@@ -81,7 +109,7 @@ function testPluginLoading() {
     $this->assertPluginClass($module, $type, 'plugin_array', 'handler');
     $this->assertPluginClass($module, $type, 'plugin_array2', 'handler');
     $this->assertPluginMissingClass($module, $type, 'plugin_array_dne', 'handler');
-    // TODO Test big hook plugins.
+    // @todo Test big hook plugins.
 
     $type = 'cached';
 
@@ -95,6 +123,7 @@ function testPluginLoading() {
     $this->assertPluginClass($module, $type, 'plugin_array', 'handler');
     $this->assertPluginClass($module, $type, 'plugin_array2', 'handler');
     $this->assertPluginMissingClass($module, $type, 'plugin_array_dne', 'handler');
-    // TODO Test big hook plugins.
+    // @todo Test big hook plugins.
   }
+
 }
diff --git a/tests/ctools_export_test/ctools_export.test b/tests/ctools_export_test/ctools_export.test
index 6a062de..baec2cd 100644
--- a/tests/ctools_export_test/ctools_export.test
+++ b/tests/ctools_export_test/ctools_export.test
@@ -1,15 +1,13 @@
 <?php
 
 /**
- * @file
  * Tests for the CTools export system.
  */
-
-/**
- * Tests export CRUD.
- */
 class CtoolsExportCrudTestCase extends DrupalWebTestCase {
 
+  /**
+   * {@inheritDoc}
+   */
   public static function getInfo() {
     return array(
       'name' => 'CTools export CRUD tests',
@@ -18,9 +16,13 @@ public static function getInfo() {
     );
   }
 
-  protected function setUp() {
-    parent::setUp('ctools_export_test');
-    $this->resetAll();
+  /**
+   * {@inheritDoc}
+   */
+  function setUp(array $modules = array()) {
+    $modules[] = 'ctools';
+    $modules[] = 'ctools_export_test';
+    parent::setUp($modules);
   }
 
   /**
@@ -135,7 +137,8 @@ function testCrudExportRevert() {
     // Check the exportable is now in_code_only.
     $this->assertTrue($default_export->in_code_only, 'The loaded exportable is in the database only.');
 
-    // Make sure the default object loaded matches the same overridden one in the database.
+    // Make sure the default object loaded matches the same overridden one in
+    // the database.
     $this->assertEqual($original_export->machine, $default_export->machine, 'The default exportable has been loaded and matches the overridden exportable.');
   }
 
@@ -158,6 +161,7 @@ function testCrudExportDelete() {
 
     $machine = $database_export->machine;
     ctools_export_crud_delete('ctools_export_test', $database_export);
+
     // Clear the exportable caches as it's been loaded above.
     ctools_export_load_object_reset('ctools_export_test');
     $result = ctools_export_crud_load('ctools_export_test', $machine);
diff --git a/tests/ctools_plugin_test.info b/tests/ctools_plugin_test.info
index ca02e26..4798fe2 100644
--- a/tests/ctools_plugin_test.info
+++ b/tests/ctools_plugin_test.info
@@ -4,10 +4,4 @@ package = Chaos tool suite
 version = CTOOLS_MODULE_VERSION
 core = 7.x
 dependencies[] = ctools
-files[] = ctools.plugins.test
-files[] = object_cache.test
-files[] = css.test
-files[] = context.test
-files[] = math_expression.test
-files[] = math_expression_stack.test
 hidden = TRUE
diff --git a/tests/ctools_plugin_test.module b/tests/ctools_plugin_test.module
index 567f6e7..a1c587d 100644
--- a/tests/ctools_plugin_test.module
+++ b/tests/ctools_plugin_test.module
@@ -1,10 +1,12 @@
 <?php
+
 /**
- * Define some plugin systems to test ctools plugin includes.
+ * @file
+ * Define some plugin systems to test CTools plugin includes.
  */
 
 /**
- * Implementation of hook_ctools_plugin_dierctory()
+ * Implementation of hook_ctools_plugin_directory().
  */
 function ctools_plugin_test_ctools_plugin_directory($module, $plugin) {
   if ($module == 'ctools_plugin_test') {
@@ -12,6 +14,9 @@ function ctools_plugin_test_ctools_plugin_directory($module, $plugin) {
   }
 }
 
+/**
+ * Implements hook_ctools_plugin_type().
+ */
 function ctools_plugin_test_ctools_plugin_type() {
   return array(
     'extra_defaults' => array(
@@ -50,6 +55,11 @@ function ctools_plugin_test_ctools_plugin_type() {
   );
 }
 
+/**
+ * Plugin callback.
+ *
+ * @see ctools_plugin_test_ctools_plugin_type()
+ */
 function ctools_plugin_test_ctools_plugin_test_big_hook_cached() {
   return array(
     'test1' => array(
@@ -59,6 +69,11 @@ function ctools_plugin_test_ctools_plugin_test_big_hook_cached() {
   );
 }
 
+/**
+ * Plugin callback.
+ *
+ * @see ctools_plugin_test_ctools_plugin_type()
+ */
 function ctools_plugin_test_ctools_plugin_test_big_hook_not_cached() {
   return array(
     'test1' => array(
@@ -68,5 +83,16 @@ function ctools_plugin_test_ctools_plugin_test_big_hook_not_cached() {
   );
 }
 
+/**
+ * Callback for the big_hook_cached plugin.
+ *
+ * @see ctools_plugin_test_ctools_plugin_test_big_hook_cached
+ */
 function ctools_plugin_test_hook_cached_test() {}
+
+/**
+ * Callback for the big_hook_not_cached plugin.
+ *
+ * @see ctools_plugin_test_ctools_plugin_test_big_hook_not_cached()
+ */
 function ctools_plugin_test_hook_not_cached_test() {}
diff --git a/tests/math_expression.test b/tests/math_expression.test
index 8810e8c..143b409 100644
--- a/tests/math_expression.test
+++ b/tests/math_expression.test
@@ -1,14 +1,13 @@
 <?php
 
 /**
- * @file
- * Contains \CtoolsMathExpressionTestCase.
- */
-
-/**
  * Tests the MathExpression library of ctools.
  */
 class CtoolsMathExpressionTestCase extends DrupalWebTestCase {
+
+  /**
+   * {@inheritDoc}
+   */
   public static function getInfo() {
     return array(
       'name' => 'CTools math expression tests',
@@ -17,8 +16,13 @@ public static function getInfo() {
     );
   }
 
-  public function setUp() {
-    parent::setUp('ctools', 'ctools_plugin_test');
+  /**
+   * {@inheritDoc}
+   */
+  function setUp(array $modules = array()) {
+    $modules[] = 'ctools';
+    $modules[] = 'ctools_plugin_test';
+    parent::setUp($modules);
   }
 
   /**
@@ -35,6 +39,9 @@ protected function assertFloat($first, $second, $delta = 0.0000001, $message = '
     return $this->assert(abs($first - $second) <= $delta, $message ? $message : t('Value @first is equal to value @second.', array('@first' => var_export($first, TRUE), '@second' => var_export($second, TRUE))), $group);
   }
 
+  /**
+   * Test some arithmetic handling.
+   */
   public function testArithmetic() {
     $math_expression = new ctools_math_expr();
 
@@ -66,10 +73,13 @@ public function testArithmetic() {
     $this->assertEqual(pow($random_number_a, $random_number_b), $math_expression->e("$random_number_a ^ $random_number_b"));
   }
 
+  /**
+   * Test 
+   */
   public function testBuildInFunctions() {
     $math_expression = new ctools_math_expr();
 
-    // @todo: maybe run this code multiple times to test different values.
+    // @todo Maybe run this code multiple times to test different values.
     $random_double = $this->rand01();
     $random_int = rand(5, 10);
     $this->assertFloat(sin($random_double), $math_expression->e("sin($random_double)"));
@@ -94,6 +104,9 @@ public function testBuildInFunctions() {
 //    $this->assertFloat(min($random_double_a, $random_double_b), $math_expression->e("min($random_double_a, $random_double_b)"));
   }
 
+  /**
+   * Test variable handling.
+   */
   public function testVariables() {
     $math_expression = new ctools_math_expr();
 
@@ -108,6 +121,9 @@ public function testVariables() {
     $this->assertEqual($random_number_a / $random_number_b, $math_expression->e("var / $random_number_b"));
   }
 
+  /**
+   * Test custom function handling.
+   */
   public function testCustomFunctions() {
     $math_expression = new ctools_math_expr();
 
@@ -126,4 +142,5 @@ public function testCustomFunctions() {
     // Use a custom function in another function.
     $this->assertEqual(($random_number_a * 2 + $random_number_b) * 2, $math_expression->e("f(g($random_number_a, $random_number_b))"));
   }
+
 }
diff --git a/tests/math_expression_stack.test b/tests/math_expression_stack.test
index bdd4695..8a06d89 100644
--- a/tests/math_expression_stack.test
+++ b/tests/math_expression_stack.test
@@ -1,14 +1,13 @@
 <?php
 
 /**
- * @file
- * Contains \CtoolsMathExpressionStackTestCase
- */
-
-/**
  * Tests the simple MathExpressionStack class.
  */
 class CtoolsMathExpressionStackTestCase extends DrupalWebTestCase {
+
+  /**
+   * {@inheritDoc}
+   */
   public static function getInfo() {
     return array(
       'name' => 'CTools math expression stack tests',
@@ -17,10 +16,18 @@ public static function getInfo() {
     );
   }
 
-  public function setUp() {
-    parent::setUp('ctools', 'ctools_plugin_test');
+  /**
+   * {@inheritDoc}
+   */
+  function setUp(array $modules = array()) {
+    $modules[] = 'ctools';
+    $modules[] = 'ctools_plugin_test';
+    parent::setUp($modules);
   }
 
+  /**
+   * Test the math expression stack system.
+   */
   public function testStack() {
     $stack = new ctools_math_expr_stack();
 
@@ -35,13 +42,15 @@ public function testStack() {
     $this->assertIdentical($value, $stack->pop());
     $this->assertNull($stack->pop());
 
-    // Add multiple elements and see whether they are returned in the right order.
+    // Add multiple elements and see whether they are returned in the right
+    // order.
     $values = array($this->randomName(), $this->randomName(), $this->randomName());
     foreach ($values as $value) {
       $stack->push($value);
     }
 
-    // Test the different elements at different positions with the last() method.
+    // Test the different elements at different positions with the last()
+    // method.
     $count = count($values);
     foreach ($values as $key => $value) {
       $this->assertEqual($value, $stack->last($count - $key));
@@ -58,6 +67,6 @@ public function testStack() {
       $this->assertEqual($stack->pop(), $value);
     }
     $this->assertNull($stack->pop());
-
   }
+
 }
diff --git a/tests/object_cache.test b/tests/object_cache.test
index 2e714d6..a699e1d 100644
--- a/tests/object_cache.test
+++ b/tests/object_cache.test
@@ -1,13 +1,13 @@
 <?php
-/**
- * @file
- * Tests for different parts of the ctools object caching system.
- */
 
 /**
  * Test object cache storage.
  */
 class CtoolsObjectCache extends DrupalWebTestCase {
+
+  /**
+   * {@inheritDoc}
+   */
   public static function getInfo() {
     return array(
       'name' => 'Ctools object cache storage',
@@ -16,12 +16,20 @@ public static function getInfo() {
     );
   }
 
-  public function setUp() {
-    // Additionally enable ctools module.
-    parent::setUp('ctools');
+  /**
+   * {@inheritDoc}
+   */
+  function setUp(array $modules = array()) {
+    $modules[] = 'ctools';
+    parent::setUp($modules);
   }
 
+  /**
+   *
+   */
   public function testObjectStorage() {
+    ctools_include('cache');
+
     $account1 = $this->drupalCreateUser(array());
     $this->drupalLogin($account1);
 
diff --git a/tests/object_cache_unit.test b/tests/object_cache_unit.test
new file mode 100644
index 0000000..1bb4af0
--- /dev/null
+++ b/tests/object_cache_unit.test
@@ -0,0 +1,138 @@
+<?php
+
+/**
+ * Test ctools_cache_find_plugin and the structure of the default cache plugins.
+ */
+class CtoolsUnitObjectCachePlugins extends DrupalUnitTestCase {
+
+  /**
+   * {@inheritDoc}
+   */
+  public static function getInfo() {
+    return array(
+      'name' => 'Ctools Unit object cache storage',
+      'description' => 'Verify that objects are written, readable and lockable.',
+      'group' => 'ctools',
+    );
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  function setUp(array $modules = array()) {
+    $modules[] = 'ctools';
+    parent::setUp($modules);
+  }
+
+  /**
+   * Check that the supplied array looks like a ctools cache plugin.
+   *
+   * @param mixed $p
+   *   The value to check.
+   * @param string $msg
+   *   Prefix of the assertion message.
+   */
+  public function assertValidCachePlugin($p, $msg) {
+    //$this->pass(var_export($p, TRUE));
+    $this->assertTrue(is_array($p), $msg . ': plugin is an array');
+
+    $this->assertEqual($p['plugin type'], 'cache', $msg . ': type is cache');
+
+    $this->assertTrue(array_key_exists('title', $p), $msg . ': title element exists');
+    $this->assertTrue(!empty($p['title']) && is_string($p['title']), $msg . ': title is a string');
+
+    $this->assertTrue(array_key_exists('cache get', $p), $msg . ': has a get function');
+    $this->assertTrue(!empty($p['cache get']) && is_callable($p['cache get']), $msg . ': get is executable');
+
+    $this->assertTrue(array_key_exists('cache set', $p), $msg . ': has a set function');
+    $this->assertTrue(!empty($p['cache set']) && is_callable($p['cache set']), $msg . ': set is executable');
+
+    // @todo Clear is required by the spec (cache.inc:40..48): but export_ui cache doesn't implement it.
+    $this->assertTrue(array_key_exists('cache clear', $p), $msg . ': has a clear function');
+    $this->assertTrue(is_callable($p['cache clear']), $msg . ': clear is executable');
+
+    // @todo Break is optional acc'd to spec but does anything implement it?
+    $this->assertTrue(!array_key_exists('cache break', $p) || is_callable($p['cache break']), $msg . ': break is executable');
+
+    // @todo Finalize is optional so don't fail if not there??
+    $this->assertTrue(!array_key_exists('cache finalize', $p) || is_callable($p['cache finalize']), $msg . ': finalize is executable');
+  }
+
+  /**
+   * Check the return value of the ctools_cache_find_plugin function.
+   *
+   * @param mixed $p the value to check.
+   * @param string $msg prefix of the assertion message.
+   */
+  public function assertPluginNotFound($p, $msg) {
+    //$this->pass(var_export($p, TRUE));
+    $this->assertTrue(is_array($p), $msg . ': is an array');
+    $plugin = array_shift($p);
+    $this->assertNull($plugin, $msg . ': no plugin info');
+    $data = array_shift($p);
+    $this->assertTrue(empty($data) || is_string($data), $msg . ': data string-like');
+    $this->assertTrue(empty($p), $msg . ': just two elements');
+  }
+
+  /**
+   * Check the return value of the ctools_cache_find_plugin function.
+   *
+   * @param mixed $p the value to check.
+   * @param string $msg prefix of the assertion message.
+   */
+  public function assertPluginFound($p, $msg) {
+    //$this->pass(var_export($p, TRUE));
+    $this->assertTrue(is_array($p), $msg . ': is an array');
+    $plugin = array_shift($p);
+    $this->assertTrue(is_array($plugin), $msg . ': has plugin data');
+    $data = array_shift($p);
+    $this->assertTrue(empty($data) || is_string($data), $msg . ': data is string-like');
+    $this->assertTrue(empty($p), $msg . ': just two elements');
+  }
+
+  /**
+   * Test to see that we can find the standard simple plugin.
+   */
+  public function testFindSimpleCachePlugin() {
+    ctools_include('cache');
+
+    // The simple plugin.
+    $plugin = ctools_cache_find_plugin('simple');
+    $this->assertPluginFound($plugin, 'The Simple Cache plugin is present');
+    $this->assertValidCachePlugin($plugin[0], 'The Simple Cache plugin');
+
+    // The simple plugin, with ::.
+    $plugin = ctools_cache_find_plugin('simple::data');
+    $this->assertPluginFound($plugin, 'The Simple Cache plugin is present, with data');
+  }
+
+  /**
+   * Test to see that we can find the standard export_ui plugin.
+   */
+  public function testFindExportUICachePlugin() {
+    ctools_include('cache');
+
+    // The export plugin.
+    $plugin = ctools_cache_find_plugin('export_ui');
+    $this->assertPluginFound($plugin, 'The Export UI Cache plugin is present');
+    $this->assertValidCachePlugin($plugin[0], 'The Export Cache plugin');
+
+    // The export plugin, with ::.
+    $plugin = ctools_cache_find_plugin('export_ui::data');
+    $this->assertTrue(is_array($plugin), 'The Export UI Cache plugin is present, with data');
+  }
+
+  /**
+   * Test to see that we don't find plugins that aren't there.
+   */
+  public function testFindFoobarbazCachePlugin() {
+    ctools_include('cache');
+
+    // An imaginary foobarbaz plugin.
+    $plugin = ctools_cache_find_plugin('foobarbaz');
+    $this->assertPluginNotFound($plugin, 'The Foobarbaz Cache plugin is absent');
+    $plugin = ctools_cache_find_plugin('foobarbaz::data');
+    $this->assertPluginNotFound($plugin, 'The Foobarbaz Cache plugin is absent, with data');
+  }
+
+}
diff --git a/tests/page_tokens.test b/tests/page_tokens.test
new file mode 100644
index 0000000..eca1aaf
--- /dev/null
+++ b/tests/page_tokens.test
@@ -0,0 +1,137 @@
+<?php
+/**
+ * @file
+ * Tests for different parts of the ctools object caching system.
+ */
+
+/**
+ * Test ctools page token processing.
+ *
+ * Needs to be a WebTest because need access to database tables.
+ */
+class CtoolsPageTokens extends DrupalWebTestCase {
+
+  /**
+   * {@inheritDoc}
+   */
+  public static function getInfo() {
+    return array(
+      'name' => 'Ctools Unit page token processing',
+      'description' => 'Verify that page tokens can be set and read.',
+      'group' => 'ctools',
+    );
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  function setUp(array $modules = array()) {
+    $modules[] = 'ctools';
+    parent::setUp($modules);
+
+    // Start each test anew.
+    ctools_reset_page_tokens();
+  }
+
+  /**
+   * Test that we can set page tokens.
+   */
+  public function testSetPageToken() {
+    ctools_set_page_token('id', 'variable', 'test');
+
+    $tokens = ctools_set_page_token();
+    $this->assertTrue(is_array($tokens) && count($tokens) === 1, 'Page tokens no longer empty.');
+    $this->assertEqual($tokens['id'], array('variable', 'test'), 'Page token has correct value.');
+  }
+
+  /**
+   * Test that we can set page tokens.
+   */
+  public function testSetVariableToken() {
+    $string = ctools_set_variable_token('title');
+    $tokens = ctools_set_page_token();
+
+    $this->assertTrue(is_array($tokens) && count($tokens) === 1, 'Page tokens no longer empty');
+    $this->assertEqual($tokens[$string], array('variable', 'title'), 'Page tokens no longer empty');
+  }
+
+  /**
+   * Test that we can set page tokens.
+   */
+  public function testReplaceVariableToken() {
+    $string = ctools_set_variable_token('title');
+    $this->assertEqual($string, '<!-- ctools-page-title -->', 'Expected form of token was found');
+
+    $elements = array(
+      '#type' => 'container',
+      '#attributes' => array('class' => array('test')),
+      'title' => '<h2>Title</h2>',
+      'content' => array(
+        '#type' => 'markup',
+        '#markup' => t('This is my test markup'),
+        '#prefix' => $string,
+      ),
+      'link' => array(
+        '#type' => 'link',
+        '#title' => t('My link'),
+        '#href' => 'node/1',
+      ),
+    );
+    $markup = '<div class="test"><!-- ctools-page-title -->This is my test markup<a href="node/1">My link</a></div>';
+
+    $new_markup = ctools_page_token_processing($markup, $elements);
+
+    $this->assertTrue(is_string($new_markup) && strlen($new_markup) > 1, 'Should return string');
+
+    $this->assertTrue(strstr($new_markup, '<h2>'), 'Variable Token Markup should contain h2 element');
+    $this->assertFalse(strstr($new_markup, 'ctools-page-title'), 'Variable Token Markup should not contain comment element');
+  }
+
+  /**
+   * Test that we can set page tokens.
+   */
+  public function testReplaceCallbackToken() {
+    $string = ctools_set_callback_token('title', 'test_ctools_page_callback_token');
+    $this->assertEqual($string, '<!-- ctools-page-title -->', 'Expected form of token was found');
+
+    $elements = array(
+      '#type' => 'container',
+      '#attributes' => array('class' => array('test')),
+      'content' => array(
+        '#type' => 'markup',
+        '#markup' => t('This is my test markup'),
+        '#prefix' => $string,
+      ),
+      'link' => array(
+        '#type' => 'link',
+        '#title' => t('My link'),
+        '#href' => 'node/1',
+      ),
+    );
+    $markup = '<div class="test"><!-- ctools-page-title -->This is my test markup<a href="node/1">My link</a></div>';
+
+    $new_markup = ctools_page_token_processing($markup, $elements);
+
+    $this->assertTrue(is_string($new_markup) && strlen($new_markup) > 1, 'Should return a non-empty string');
+
+    $this->assertTrue(strstr($new_markup, '<h2>'), 'Callback Token Markup should contain h2 element');
+    $this->assertFalse(strstr($new_markup, 'ctools-page-title'), 'Callback Token Markup should not contain comment element');
+  }
+
+}
+
+/**
+ *
+ * @param $elements
+ *
+ * @return string
+ */
+function test_ctools_page_callback_token($elements) {
+  // Check that 'elements' array looks good.
+  if (isset($elements['content'])) {
+    return '<h2>Title</h2>';
+  }
+  else {
+    return '<!--bad-->';
+  }
+}
diff --git a/tests/uuid_with_uuid.test b/tests/uuid_with_uuid.test
new file mode 100644
index 0000000..23b3db1
--- /dev/null
+++ b/tests/uuid_with_uuid.test
@@ -0,0 +1,49 @@
+<?php
+
+/**
+ * Test ctools_cache_find_plugin and the structure of the default cache plugins.
+ */
+class CtoolsWebUUIDWithUUIDtests extends DrupalWebTestCase {
+
+  /**
+   * {@inheritDoc}
+   */
+  public static function getInfo() {
+    return array(
+      'name' => 'CTools unit tests with the UUID module',
+      'description' => 'Check that the CTools UUID functions behave correctly when UUID .',
+      'group' => 'ctools',
+    );
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  function setUp(array $modules = array()) {
+    $modules[] = 'ctools';
+    parent::setUp($modules);
+  }
+
+  /**
+   * Check we can get a UUID.
+   *
+   * NB: This test will use one (and only one) of the mechanisms available
+   * from pear,
+   */
+  public function testMakeNewUUIDmodule() {
+    // drupal_get_filename will report even if the module is disabled.
+    if (drupal_get_filename('module', 'uuid') && !module_exists('uuid')) {
+      module_enable(array('uuid'));
+    }
+    // if we now have uuid module, use it.
+    if (module_exists('uuid')) {
+      $uuid = ctools_uuid_generate();
+      $this->assertTrue(ctools_uuid_is_valid($uuid), 'UUID generated (uuid): ' . $uuid);
+    }
+    else {
+      // otherwise say we can't...
+      $this->verbose('uuid module not present');
+    }
+  }
+
+}
diff --git a/tests/uuid_without_uuid.test b/tests/uuid_without_uuid.test
new file mode 100644
index 0000000..ba2bad5
--- /dev/null
+++ b/tests/uuid_without_uuid.test
@@ -0,0 +1,92 @@
+<?php
+
+/**
+ * Test the UUID handling without the UUID module being present.
+ */
+class CtoolsWebUUIDWithoutUUIDtests extends DrupalWebTestCase {
+
+  /**
+   * {@inheritDoc}
+   */
+  public static function getInfo() {
+    return array(
+      'name' => 'CTools unit tests for mini-UUID',
+      'description' => 'Check that the CTools UUID functions behave correctly.',
+      'group' => 'ctools',
+    );
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  function setUp(array $modules = array()) {
+    $modules[] = 'ctools';
+    parent::setUp($modules);
+  }
+
+  /**
+   * Check the define UUID_PATTERN exists.
+   */
+  public function testHaveUUIDpattern() {
+    ctools_include('uuid');
+    $this->assertTrue(defined('UUID_PATTERN'), 'UUID constant exists');
+    $this->assertTrue(is_string(UUID_PATTERN) && strlen(UUID_PATTERN) > 12, 'UUID pattern exists');
+  }
+
+  /**
+   * Check we can get a UUID when .
+   *
+   * NB: This test will use one (and only one) of the mechanisms available
+   * from pear,
+   */
+  public function testMakeNewUUIDctoolsphp() {
+    // drupal_get_filename will report even if the module is disabled.
+    if (drupal_get_filename('module', 'uuid') && module_exists('uuid')) {
+      module_disable(array('uuid'));
+    }
+
+    ctools_include('uuid');
+    $uuid = _ctools_uuid_generate_php();
+    $this->assertTrue(ctools_uuid_is_valid($uuid), 'UUID generated (ctoolsphp): ' . $uuid);
+  }
+
+  /**
+   * Check we can get a UUID when .
+   *
+   * NB: This test will use one (and only one) of the mechanisms available
+   * from pear,
+   */
+  public function testMakeNewUUIDnomodule() {
+    // drupal_get_filename will report even if the module is disabled.
+    if (drupal_get_filename('module', 'uuid') && module_exists('uuid')) {
+      module_disable(array('uuid'));
+    }
+
+    $uuid = ctools_uuid_generate();
+    $this->assertTrue(ctools_uuid_is_valid($uuid), 'UUID generated (ctools): ' . $uuid);
+  }
+
+  /**
+   * Check we can verify that a string looks like a UUID.
+   */
+  public function testVerifyUUID() {
+    $checks = array(
+      NULL => FALSE,
+      '' => FALSE,
+      '0' => FALSE,
+      'b5827a5cadd311e69a1f936389a27663' => FALSE,  // version 1, no dashes
+      '15ff2566-add3-11e6-b98f' => FALSE,           // incomplete
+
+      '15ff2566-add3-11e6-b98f-080027dc4f7a' => TRUE, // version 1
+      'b5827a5c-add3-11e6-9a1f-936389a27663' => TRUE, // version 1
+      '02d9e6d5-9467-382e-8f9b-9300a64ac3cd' => TRUE, // version 3 url-based
+      '5e330afb-50c6-45c2-a292-99c3168696d2' => TRUE, // version 4 uuid
+      '8f4ca4fd-154e-5063-b6db-aa91af137037' => TRUE, // version 5
+    );
+
+    foreach($checks as $uuid => $exp) {
+      $this->assertEqual(ctools_uuid_is_valid($uuid), $exp, 'Is Valid: UUIDs match expectations: ' . $uuid);
+    }
+  }
+
+}
