MDL-38298 Take out harcoded dependency + tests.

With that change the filte_emoticon will be easily
resusable by other "emoticon filters".

filter/emoticon/filter.php

@@ -96,7 +96,7 @@ protected function get_global_config($name=null) {
      */
     protected function load_global_config() {
         if (is_null(self::$globalconfig)) {
-            self::$globalconfig = get_config('filter_emoticon');
+            self::$globalconfig = get_config(get_class($this));
         }
     }
 

filter/emoticon/tests/filter_test.php

@@ -0,0 +1,74 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Skype icons filter phpunit tests
+ *
+ * @package    filter_emoticon
+ * @category   test
+ * @copyright  2013 onwards Eloy Lafuente (stronk7) {@link http://stronk7.com}
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+defined('MOODLE_INTERNAL') || die();
+
+global $CFG;
+require_once($CFG->dirroot . '/filter/emoticon/filter.php'); // Include the code to test.
+
+/**
+ * Skype icons filter testcase.
+ */
+class filter_emoticon_testcase extends advanced_testcase {
+
+    /**
+     * Verify configured target formats are observed. Just that.
+     */
+    public function test_filter_emoticon_formats() {
+
+        $this->resetAfterTest(true); // We are modifying the config.
+
+        $filter = new testable_filter_emoticon();
+
+        // Verify texts not matching target formats aren't filtered.
+        $expected = '(grr)';
+        $options = array('originalformat' => FORMAT_MOODLE); // Only FORMAT_HTML is filtered, see {@link testable_filter_emoticon}.
+        $this->assertEquals($expected, $filter->filter('(grr)', $options));
+
+        $options = array('originalformat' => FORMAT_MARKDOWN); // Only FORMAT_HTML is filtered, see {@link testable_filter_emoticon}.
+        $this->assertEquals($expected, $filter->filter('(grr)', $options));
+
+        $options = array('originalformat' => FORMAT_PLAIN); // Only FORMAT_HTML is filtered, see {@link testable_filter_emoticon}.
+        $this->assertEquals($expected, $filter->filter('(grr)', $options));
+
+        // And texts matching target formats are filtered.
+        $expected = '<img class="emoticon" alt="angry" title="angry"'.
+                    ' src="http://www.example.com/moodle/theme/image.php/_s/standard/core/1/s/angry" />';
+        $options = array('originalformat' => FORMAT_HTML); // Only FORMAT_HTML is filtered, see {@link testable_filter_emoticon}.
+        $this->assertEquals($expected, $filter->filter('(grr)', $options));
+    }
+}
+
+/**
+ * Subclass for easier testing.
+ */
+class testable_filter_emoticon extends filter_emoticon {
+    public function __construct() {
+        // Use this context for filtering.
+        $this->context = context_system::instance();
+        // Define FORMAT_HTML as only one filtering in DB.
+        set_config('formats', implode(',', array(FORMAT_HTML)), get_class($this));
+    }
+}