Add a syntax highlight dropdown, if pygments is enabled.

Summary:
- Add a default list of supported languages to default.conf.php
  and make the initial/default value customizable.
- Store a '' in the database to infer the language from the filename/title.

Test Plan:
Tested in my sandbox with pygments enabled and disabled and various
combinations of filename/extension/dropdown selection.

Reviewers:
epriestley

CC:

Differential Revision: 587

conf/default.conf.php

@@ -305,14 +305,6 @@ return array(
   // behalf, silencing the warning.
   'phabricator.timezone'        => null,
 
-
-  // Phabricator can highlight PHP by default, but if you want syntax
-  // highlighting for other languages you should install the python package
-  // 'Pygments', make sure the 'pygmentize' script is available in the
-  // $PATH of the webserver, and then enable this.
-  'pygments.enabled'            => false,
-
-
 // -- Files ----------------------------------------------------------------- //
 
   // Lists which uploaded file types may be viewed in the browser. If a file
@@ -416,4 +408,41 @@ return array(
   // settings are the defaults.)
   'celerity.force-disk-reads' => false,
 
+  // -- Pygments ------------------------------------------------------------ //
+  // Phabricator can highlight PHP by default, but if you want syntax
+  // highlighting for other languages you should install the python package
+  // 'Pygments', make sure the 'pygmentize' script is available in the
+  // $PATH of the webserver, and then enable this.
+  'pygments.enabled'            => false,
+
+  // In places that we display a dropdown to syntax-highlight code,
+  // this is where that list is defined.
+  // Syntax is 'lexer-name' => 'Display Name',
+  'pygments.dropdown-choices' => array(
+    'apacheconf' => 'Apache Configuration',
+    'bash' => 'Bash Scripting',
+    'brainfuck' => 'Brainf*ck',
+    'c' => 'C',
+    'cpp' => 'C++',
+    'css' => 'CSS',
+    'diff' => 'Diff',
+    'django' => 'Django Templating',
+    'erb' => 'Embedded Ruby/ERB',
+    'erlang' => 'Erlang',
+    'html' => 'HTML',
+    'infer' => 'Infer from title (extension)',
+    'java' => 'Java',
+    'js' => 'Javascript',
+    'mysql' => 'MySQL',
+    'perl' => 'Perl',
+    'php' => 'PHP',
+    'text' => 'Plain Text',
+    'python' => 'Python',
+    // TODO: 'remarkup' => 'Remarkup',
+    'ruby' => 'Ruby',
+    'xml' => 'XML',
+  ),
+
+  'pygments.dropdown-default' => 'infer',
+
 );

resources/sql/patches/052.pastelanguage.sql

@@ -0,0 +1,2 @@
+ALTER TABLE phabricator_pastebin.pastebin_paste
+  ADD COLUMN language VARCHAR(64) NOT NULL;

src/applications/differential/data/commitmessage/__init__.php

@@ -11,7 +11,6 @@ phutil_require_module('phabricator', 'applications/differential/storage/comment'
 phutil_require_module('phabricator', 'applications/phid/handle/data');
 phutil_require_module('phabricator', 'infrastructure/env');
 
-phutil_require_module('phutil', 'symbols');
 phutil_require_module('phutil', 'utils');
 
 

src/applications/paste/controller/create/PhabricatorPasteCreateController.php

@@ -31,6 +31,16 @@ class PhabricatorPasteCreateController extends PhabricatorPasteController {
     if ($request->isFormPost()) {
       $errors = array();
       $title = $request->getStr('title');
+
+      $language = $request->getStr('language');
+      if ($language == 'infer') {
+        // If it's infer, store an empty string. Otherwise, store the
+        // language name. We do this so we can refer to 'infer' elsewhere
+        // in the code (such as default value) while retaining backwards
+        // compatibility with old posts with no language stored.
+        $language = '';
+      }
+
       $text = $request->getStr('text');
 
       if (!strlen($text)) {
@@ -41,6 +51,7 @@ class PhabricatorPasteCreateController extends PhabricatorPasteController {
       }
 
       $paste->setTitle($title);
+      $paste->setLanguage($language);
 
       if (!$errors) {
         $paste_file = PhabricatorFile::newFromFileData(
@@ -76,6 +87,26 @@ class PhabricatorPasteCreateController extends PhabricatorPasteController {
     }
 
     $form = new AphrontFormView();
+
+    // If we're coming back from an error and the language was already defined,
+    // use that. Otherwise, ask the config for the default.
+    if ($paste->getLanguage()) {
+      $language_default = $paste->getLanguage();
+    } else {
+      $language_default = PhabricatorEnv::getEnvConfig(
+        'pygments.dropdown-default');
+    }
+
+    $available_languages = PhabricatorEnv::getEnvConfig(
+      'pygments.dropdown-choices');
+    asort($available_languages);
+
+    $language_select = id(new AphrontFormSelectControl())
+      ->setLabel('Language')
+      ->setName('language')
+      ->setValue($language_default)
+      ->setOptions($available_languages);
+
     $form
       ->setUser($user)
       ->setAction($request->getRequestURI()->getPath())
@@ -84,6 +115,7 @@ class PhabricatorPasteCreateController extends PhabricatorPasteController {
           ->setLabel('Title')
           ->setValue($paste->getTitle())
           ->setName('title'))
+      ->appendChild($language_select)
       ->appendChild(
         id(new AphrontFormTextAreaControl())
           ->setLabel('Text')

src/applications/paste/controller/create/__init__.php

@@ -10,7 +10,9 @@ phutil_require_module('phabricator', 'aphront/response/redirect');
 phutil_require_module('phabricator', 'applications/files/storage/file');
 phutil_require_module('phabricator', 'applications/paste/controller/base');
 phutil_require_module('phabricator', 'applications/paste/storage/paste');
+phutil_require_module('phabricator', 'infrastructure/env');
 phutil_require_module('phabricator', 'view/form/base');
+phutil_require_module('phabricator', 'view/form/control/select');
 phutil_require_module('phabricator', 'view/form/control/submit');
 phutil_require_module('phabricator', 'view/form/control/text');
 phutil_require_module('phabricator', 'view/form/control/textarea');

src/applications/paste/controller/view/PhabricatorPasteViewController.php

@@ -96,7 +96,7 @@ class PhabricatorPasteViewController extends PhabricatorPasteController {
 
     $text_list = explode(
       "\n", $highlightEngine->highlightSource(
-        $paste->getTitle(),
+        nonempty($paste->getLanguage(), $paste->getTitle()),
         $file->loadFileData()));
 
     $rows = $this->buildDisplayRows($text_list);

src/applications/paste/storage/paste/PhabricatorPaste.php

@@ -22,6 +22,7 @@ class PhabricatorPaste extends PhabricatorPasteDAO {
   protected $title;
   protected $authorPHID;
   protected $filePHID;
+  protected $language;
 
   public function getConfiguration() {
     return array(