add escape_tags test

tests/unit/includes/TextTest.php

@@ -102,6 +102,26 @@ empty line above';
         ];
     }
 
+    /**
+     * @dataProvider escapeTagsProvider
+     */
+    public function testEscapeTags($string, $expected)
+    {
+        $this->assertEquals($expected, escape_tags($string));
+    }
+    public static function escapeTagsProvider()
+    {
+        return [
+            'empty string' => ['', ''],
+            'simple tag' => ['<value>', '&lt;value&gt;'],
+            'tag pair' => ['<b>text</b>', '&lt;b&gt;text&lt;/b&gt;'],
+            'double angle bracket' => ['<<value', '&lt;&lt;value'],
+            'ampersand' => ['&&foo&&', '&amp;&amp;foo&amp;&amp;'],
+            'HTML entity &gt;' => ['&gt;', '&gt;']
+        ];
+    }
+
+
     /**
      * @dataProvider sanitise_aclProvider
      */