Add AutoFormat.LinkifyEmail Option.

If enabled, automatically provide links to e-mail addresses.
For example,
  Send an e-mail to user@example.com.
is transformed to
  Send an e-mail to <a href="mailto:user@example.com">user@example.com</a>.

Signed-off-by: Bradley M. Froehle <brad.froehle@gmail.com>

NEWS

@@ -22,6 +22,8 @@ NEWS ( CHANGELOG and HISTORY )                                     HTMLPurifier
   directory/file permissions
 ! Fix longstanding bug in Flash support for non-IE browsers, and
   allow more wmode attributes.
+! Add %AutoFormat.LinkifyEmail option for automatically linking
+  to e-mail addresses.
 - Switch to an iterative traversal of the DOM, which prevents us
   from running out of stack space for deeply nested documents.
   Thanks Maxim Krizhanovsky for contributing a patch.

configdoc/usage.xml

@@ -254,6 +254,9 @@
   <file name="HTMLPurifier/URIDefinition.php">
    <line>64</line>
   </file>
+  <file name="HTMLPurifier/URIScheme.php">
+   <line>75</line>
+  </file>
  </directive>
  <directive id="URI.Base">
   <file name="HTMLPurifier/URIDefinition.php">

library/HTMLPurifier.includes.php

@@ -176,6 +176,7 @@ require 'HTMLPurifier/HTMLModule/Tidy/XHTML.php';
 require 'HTMLPurifier/Injector/AutoParagraph.php';
 require 'HTMLPurifier/Injector/DisplayLinkURI.php';
 require 'HTMLPurifier/Injector/Linkify.php';
+require 'HTMLPurifier/Injector/LinkifyEmail.php';
 require 'HTMLPurifier/Injector/PurifierLinkify.php';
 require 'HTMLPurifier/Injector/RemoveEmpty.php';
 require 'HTMLPurifier/Injector/RemoveSpansWithoutAttributes.php';

library/HTMLPurifier.safe-includes.php

@@ -170,6 +170,7 @@ require_once $__dir . '/HTMLPurifier/HTMLModule/Tidy/XHTML.php';
 require_once $__dir . '/HTMLPurifier/Injector/AutoParagraph.php';
 require_once $__dir . '/HTMLPurifier/Injector/DisplayLinkURI.php';
 require_once $__dir . '/HTMLPurifier/Injector/Linkify.php';
+require_once $__dir . '/HTMLPurifier/Injector/LinkifyEmail.php';
 require_once $__dir . '/HTMLPurifier/Injector/PurifierLinkify.php';
 require_once $__dir . '/HTMLPurifier/Injector/RemoveEmpty.php';
 require_once $__dir . '/HTMLPurifier/Injector/RemoveSpansWithoutAttributes.php';

library/HTMLPurifier/ConfigSchema/schema/AutoFormat.LinkifyEmail.txt

@@ -0,0 +1,12 @@
+AutoFormat.LinkifyEmail
+TYPE: bool
+VERSION: 4.3.0
+DEFAULT: false
+--DESCRIPTION--
+
+<p>
+  This directive turns on e-mail linkification, auto-linking e-mail addresses.
+  <code>a</code> tags with the <code>href</code> attribute
+  must be allowed.
+</p>
+--# vim: et sw=4 sts=4

library/HTMLPurifier/Injector/LinkifyEmail.php

@@ -0,0 +1,43 @@
+<?php
+
+/**
+ * Injector that converts e-mails to actual links.
+ */
+class HTMLPurifier_Injector_LinkifyEmail extends HTMLPurifier_Injector
+{
+
+    public $name = 'LinkifyEmail';
+    public $needed = array('a' => array('href'));
+
+    public function handleText(&$token) {
+        if (!$this->allowsElement('a')) return;
+
+        if (strpos($token->data, '@') === false) {
+            // our really quick heuristic failed, abort
+            return;
+        }
+
+        // e-mail regex comes from Drupal 7, see http://api.drupal.org/_filter_url
+        $bits = preg_split('#([A-Za-z0-9._-]+@(?:(?:[A-Za-z0-9._+-]+\.)?[A-Za-z]{2,64}\b))#S', $token->data, -1, PREG_SPLIT_DELIM_CAPTURE);
+
+        $token = array();
+
+        // $i = index
+        // $c = count
+        // $l = is link
+        for ($i = 0, $c = count($bits), $l = false; $i < $c; $i++, $l = !$l) {
+            if (!$l) {
+                if ($bits[$i] === '') continue;
+                $token[] = new HTMLPurifier_Token_Text($bits[$i]);
+            } else {
+                $token[] = new HTMLPurifier_Token_Start('a', array('href' => 'mailto:' . $bits[$i]));
+                $token[] = new HTMLPurifier_Token_Text($bits[$i]);
+                $token[] = new HTMLPurifier_Token_End('a');
+            }
+        }
+
+    }
+
+}
+
+// vim: et sw=4 sts=4

tests/HTMLPurifier/Injector/LinkifyEmailTest.php

@@ -0,0 +1,50 @@
+<?php
+
+class HTMLPurifier_Injector_LinkifyEmailTest extends HTMLPurifier_InjectorHarness
+{
+
+    function setup() {
+        parent::setup();
+        $this->config->set('AutoFormat.LinkifyEmail', true);
+    }
+
+    function testLinkifyEmailInRootNode() {
+        $this->assertResult(
+            'user@example.com',
+            '<a href="mailto:user@example.com">user@example.com</a>'
+        );
+    }
+
+    function testLinkifyEmailLInInlineNode() {
+        $this->assertResult(
+            '<b>user@example.com</b>',
+            '<b><a href="mailto:user@example.com">user@example.com</a></b>'
+        );
+    }
+
+    function testBasicUsageCase() {
+        $this->assertResult(
+            'This e-mail user@example.com is what you need',
+            'This e-mail <a href="mailto:user@example.com">user@example.com</a> is what you need'
+        );
+    }
+
+    function testIgnoreEmailInATag() {
+        $this->assertResult(
+            '<a>user@example.com</a>'
+        );
+    }
+
+    function testNeeded() {
+        $this->config->set('HTML.Allowed', 'b');
+        $this->expectError('Cannot enable LinkifyEmail injector because a is not allowed');
+        $this->assertResult('user@example.com');
+    }
+
+    function testExcludes() {
+        $this->assertResult('<a><span>user@example.com</span></a>');
+    }
+
+}
+
+// vim: et sw=4 sts=4