theme.inc 95.4 KB
Newer Older
Dries's avatar
 
Dries committed
1
<?php
2

3
/**
Dries's avatar
 
Dries committed
4
 * @file
5
 * The theme system, which controls the output of Drupal.
Dries's avatar
 
Dries committed
6 7 8 9
 *
 * The theme system allows for nearly all output of the Drupal system to be
 * customized by user themes.
 */
Dries's avatar
 
Dries committed
10

11
use Drupal\Component\Utility\String;
12
use Drupal\Component\Utility\UrlHelper;
13
use Drupal\Component\Utility\Xss;
14
use Drupal\Core\Config\Config;
15
use Drupal\Core\Config\StorageException;
16
use Drupal\Core\Language\Language;
17
use Drupal\Core\Extension\Extension;
18
use Drupal\Core\Extension\ExtensionNameLengthException;
19
use Drupal\Core\Template\Attribute;
20
use Drupal\Core\Template\RenderWrapper;
21
use Drupal\Core\Theme\ThemeSettings;
22
use Drupal\Component\Utility\NestedArray;
23
use Drupal\Core\Render\Element;
24

25
/**
26
 * @defgroup content_flags Content markers
27 28 29 30
 * @{
 * Markers used by theme_mark() and node_mark() to designate content.
 * @see theme_mark(), node_mark()
 */
31 32 33 34

/**
 * Mark content as read.
 */
35
const MARK_READ = 0;
36 37 38 39

/**
 * Mark content as being new.
 */
40
const MARK_NEW = 1;
41 42 43 44

/**
 * Mark content as being updated.
 */
45
const MARK_UPDATED = 2;
46

47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62
/**
 * A responsive table class; hide table cell on narrow devices.
 *
 * Indicates that a column has medium priority and thus can be hidden on narrow
 * width devices and shown on medium+ width devices (i.e. tablets and desktops).
 */
const RESPONSIVE_PRIORITY_MEDIUM = 'priority-medium';

/**
 * A responsive table class; only show table cell on wide devices.
 *
 * Indicates that a column has low priority and thus can be hidden on narrow
 * and medium viewports and shown on wide devices (i.e. desktops).
 */
const RESPONSIVE_PRIORITY_LOW = 'priority-low';

63
/**
64
 * @} End of "defgroup content_flags".
65 66
 */

67 68 69
/**
 * Determines if a theme is available to use.
 *
70
 * @param string|\Drupal\Core\Extension\Extension $theme
71 72
 *   Either the name of a theme or a full theme object.
 *
73
 * @return bool
74 75
 *   Boolean TRUE if the theme is enabled or is the site administration theme;
 *   FALSE otherwise.
76
 *
77 78 79 80
 * @deprecated in Drupal 8.x-dev, will be removed before Drupal 8.0.
 *   Use \Drupal::service('access_check.theme')->checkAccess().
 *
 * @see \Drupal\Core\Theme\ThemeAccessCheck::checkAccess().
81 82
 */
function drupal_theme_access($theme) {
83
  if ($theme instanceof Extension) {
84
    $theme = $theme->getName();
85
  }
86
  return \Drupal::service('access_check.theme')->checkAccess($theme);
87 88
}

Dries's avatar
 
Dries committed
89
/**
90
 * Initializes the theme system by loading the theme.
Dries's avatar
 
Dries committed
91
 */
92
function drupal_theme_initialize() {
93
  global $theme, $theme_key;
94 95 96 97 98

  // If $theme is already set, assume the others are set, too, and do nothing
  if (isset($theme)) {
    return;
  }
Dries's avatar
 
Dries committed
99

100
  $themes = list_themes();
Dries's avatar
 
Dries committed
101

102 103 104 105 106
  // @todo Let the theme.negotiator listen to the kernel request event.
  // Determine the active theme for the theme negotiator service. This includes
  // the default theme as well as really specific ones like the ajax base theme.
  $request = \Drupal::request();
  $theme = \Drupal::service('theme.negotiator')->determineActiveTheme($request) ?: 'stark';
Dries's avatar
 
Dries committed
107 108 109 110

  // Store the identifier for retrieving theme settings with.
  $theme_key = $theme;

111 112 113 114
  // Find all our ancestor themes and put them in an array.
  $base_theme = array();
  $ancestor = $theme;
  while ($ancestor && isset($themes[$ancestor]->base_theme)) {
115
    $ancestor = $themes[$ancestor]->base_theme;
116
    $base_theme[] = $themes[$ancestor];
117
  }
118
  _drupal_theme_initialize($themes[$theme], array_reverse($base_theme));
119 120 121
}

/**
122 123 124
 * Initializes the theme system given already loaded information.
 *
 * This function is useful to initialize a theme when no database is present.
125
 *
126 127 128
 * @param \Drupal\Core\Extension\Extension $theme
 *   The theme extension object.
 * @param \Drupal\Core\Extension\Extension[] $base_theme
129 130 131 132 133 134
 *    An optional array of objects that represent the 'base theme' if the
 *    theme is meant to be derivative of another theme. It requires
 *    the same information as the $theme object. It should be in
 *    'oldest first' order, meaning the top level of the chain will
 *    be first.
 */
135
function _drupal_theme_initialize($theme, $base_theme = array()) {
136 137 138 139
  global $theme_info, $base_theme_info, $theme_engine, $theme_path;
  $theme_info = $theme;
  $base_theme_info = $base_theme;

140
  $theme_path = $theme->getPath();
141

142 143 144 145
  // Prepare stylesheets from this theme as well as all ancestor themes.
  // We work it this way so that we can have child themes override parent
  // theme stylesheets easily.
  $final_stylesheets = array();
146 147 148 149
  // CSS file basenames to override, pointing to the final, overridden filepath.
  $theme->stylesheets_override = array();
  // CSS file basenames to remove.
  $theme->stylesheets_remove = array();
150 151 152 153 154 155 156 157 158 159

  // Grab stylesheets from base theme
  foreach ($base_theme as $base) {
    if (!empty($base->stylesheets)) {
      foreach ($base->stylesheets as $media => $stylesheets) {
        foreach ($stylesheets as $name => $stylesheet) {
          $final_stylesheets[$media][$name] = $stylesheet;
        }
      }
    }
160
    $base_theme_path = $base->getPath();
161 162 163 164 165 166 167 168 169 170 171
    if (!empty($base->info['stylesheets-remove'])) {
      foreach ($base->info['stylesheets-remove'] as $basename) {
        $theme->stylesheets_remove[$basename] = $base_theme_path . '/' . $basename;
      }
    }
    if (!empty($base->info['stylesheets-override'])) {
      foreach ($base->info['stylesheets-override'] as $name) {
        $basename = drupal_basename($name);
        $theme->stylesheets_override[$basename] = $base_theme_path . '/' . $name;
      }
    }
172 173
  }

174 175 176
  // Add stylesheets used by this theme.
  if (!empty($theme->stylesheets)) {
    foreach ($theme->stylesheets as $media => $stylesheets) {
177 178 179 180 181
      foreach ($stylesheets as $name => $stylesheet) {
        $final_stylesheets[$media][$name] = $stylesheet;
      }
    }
  }
182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200
  if (!empty($theme->info['stylesheets-remove'])) {
    foreach ($theme->info['stylesheets-remove'] as $basename) {
      $theme->stylesheets_remove[$basename] = $theme_path . '/' . $basename;

      if (isset($theme->stylesheets_override[$basename])) {
        unset($theme->stylesheets_override[$basename]);
      }
    }
  }
  if (!empty($theme->info['stylesheets-override'])) {
    foreach ($theme->info['stylesheets-override'] as $name) {
      $basename = drupal_basename($name);
      $theme->stylesheets_override[$basename] = $theme_path . '/' . $name;

      if (isset($theme->stylesheets_remove[$basename])) {
        unset($theme->stylesheets_remove[$basename]);
      }
    }
  }
201

202 203
  // And now add the stylesheets properly.
  $css = array();
204 205
  foreach ($final_stylesheets as $media => $stylesheets) {
    foreach ($stylesheets as $stylesheet) {
206 207 208 209 210
      $css['#attached']['css'][$stylesheet] = array(
        'group' => CSS_AGGREGATE_THEME,
        'every_page' => TRUE,
        'media' => $media
      );
211 212
    }
  }
213
  drupal_render($css);
214

215 216
  // Do basically the same as the above for libraries
  $final_libraries = array();
217

218
  // Grab libraries from base theme
219
  foreach ($base_theme as $base) {
220 221 222
    if (!empty($base->libraries)) {
      foreach ($base->libraries as $library) {
        $final_libraries[] = $library;
223
      }
Dries's avatar
 
Dries committed
224 225
    }
  }
226

227 228 229 230
  // Add libraries used by this theme.
  if (!empty($theme->libraries)) {
    foreach ($theme->libraries as $library) {
      $final_libraries[] = $library;
231 232 233
    }
  }

234 235 236 237
  // Add libraries used by this theme.
  $libraries = array();
  foreach ($final_libraries as $library) {
    $libraries['#attached']['library'][] = $library;
238
  }
239
  drupal_render($libraries);
240

241 242 243 244 245
  $theme_engine = NULL;

  // Initialize the theme.
  if (isset($theme->engine)) {
    // Include the engine.
246
    include_once DRUPAL_ROOT . '/' . $theme->owner;
247 248

    $theme_engine = $theme->engine;
249
    if (function_exists($theme_engine . '_init')) {
250
      foreach ($base_theme as $base) {
251
        call_user_func($theme_engine . '_init', $base);
252
      }
253
      call_user_func($theme_engine . '_init', $theme);
254 255 256 257 258 259 260
    }
  }
  else {
    // include non-engine theme files
    foreach ($base_theme as $base) {
      // Include the theme file or the engine.
      if (!empty($base->owner)) {
261
        include_once DRUPAL_ROOT . '/' . $base->owner;
262 263 264 265
      }
    }
    // and our theme gets one too.
    if (!empty($theme->owner)) {
266
      include_once DRUPAL_ROOT . '/' . $theme->owner;
Dries's avatar
 
Dries committed
267 268
    }
  }
269 270

  // Always include Twig as the default theme engine.
271
  include_once DRUPAL_ROOT . '/core/themes/engines/twig/twig.engine';
Dries's avatar
 
Dries committed
272 273
}

274
/**
275
 * Gets the theme registry.
276
 *
277
 * @param bool $complete
278
 *   Optional boolean to indicate whether to return the complete theme registry
279 280 281 282 283 284 285
 *   array or an instance of the Drupal\Core\Utility\ThemeRegistry class.
 *   If TRUE, the complete theme registry array will be returned. This is useful
 *   if you want to foreach over the whole registry, use array_* functions or
 *   inspect it in a debugger. If FALSE, an instance of the
 *   Drupal\Core\Utility\ThemeRegistry class will be returned, this provides an
 *   ArrayObject which allows it to be accessed with array syntax and isset(),
 *   and should be more lightweight than the full registry. Defaults to TRUE.
286
 *
287
 * @return
288 289
 *   The complete theme registry array, or an instance of the
 *   Drupal\Core\Utility\ThemeRegistry class.
290
 */
291
function theme_get_registry($complete = TRUE) {
292
  $theme_registry = \Drupal::service('theme.registry');
293
  if ($complete) {
294
    return $theme_registry->get();
295 296
  }
  else {
297
    return $theme_registry->getRuntime();
298 299 300 301
  }
}

/**
302 303 304 305
 * Forces the system to rebuild the theme registry.
 *
 * This function should be called when modules are added to the system, or when
 * a dynamic system needs to add more theme hooks.
306
 */
307
function drupal_theme_rebuild() {
308
  \Drupal::service('theme.registry')->reset();
309 310
}

Dries's avatar
 
Dries committed
311
/**
312
 * Returns a list of all currently available themes.
Dries's avatar
 
Dries committed
313
 *
314 315
 * Retrieved from the database, if available and the site is not in maintenance
 * mode; otherwise compiled freshly from the filesystem.
316
 *
Dries's avatar
 
Dries committed
317
 * @param $refresh
318
 *   Whether to reload the list of themes from the database. Defaults to FALSE.
319
 *
320 321
 * @return array
 *   An associative array of the currently available themes.
322
 *
323 324 325 326
 * @deprecated in Drupal 8.x-dev, will be removed before Drupal 8.0.
 *   Use \Drupal::service('theme_handler')->listInfo().
 *
 * @see \Drupal\Core\Extension\ThemeHandler::listInfo().
327
 */
328
function list_themes($refresh = FALSE) {
329 330
  /** @var \Drupal\Core\Extension\ThemeHandler $theme_handler */
  $theme_handler = \Drupal::service('theme_handler');
Dries's avatar
 
Dries committed
331 332

  if ($refresh) {
333
    $theme_handler->reset();
334
    system_list_reset();
Dries's avatar
 
Dries committed
335 336
  }

337
  return $theme_handler->listInfo();
Dries's avatar
 
Dries committed
338 339
}

Dries's avatar
 
Dries committed
340
/**
341
 * Generates themed output (internal use only).
342
 *
343 344 345 346 347 348 349 350
 * _theme() is an internal function. Do not call this function directly as it
 * will prevent the following items from working correctly:
 * - Render caching.
 * - JavaScript and CSS asset attachment.
 * - Pre / post render hooks.
 * - Defaults provided by hook_element_info(), including attached assets.
 * Instead, build a render array with a #theme key, and either return the
 * array (where possible) or call drupal_render() to convert it to HTML.
351
 *
352 353 354 355 356 357
 * All requests for themed output must go through this function, which is
 * invoked as part of the @link theme_render drupal_render() process @endlink.
 * The appropriate theme function is indicated by the #theme property
 * of a renderable array. _theme() examines the request and routes it to the
 * appropriate @link themeable theme function or template @endlink, by checking
 * the theme registry.
358
 *
359
 * @param $hook
360 361
 *   The name of the theme hook to call. If the name contains a
 *   double-underscore ('__') and there isn't an implementation for the full
362
 *   name, the part before the '__' is checked. This allows a fallback to a
363
 *   more generic implementation. For example, if _theme('links__node', ...) is
364 365
 *   called, but there is no implementation of that theme hook, then the
 *   'links' implementation is used. This process is iterative, so if
366
 *   _theme('links__contextual__node', ...) is called, _theme() checks for the
367 368 369 370 371 372
 *   following implementations, and uses the first one that exists:
 *   - links__contextual__node
 *   - links__contextual
 *   - links
 *   This allows themes to create specific theme implementations for named
 *   objects and contexts of otherwise generic theme hooks. The $hook parameter
373
 *   may also be an array, in which case the first theme hook that has an
374
 *   implementation is used. This allows for the code that calls _theme() to
375
 *   explicitly specify the fallback order in a situation where using the '__'
376
 *   convention is not desired or is insufficient.
377 378
 * @param $variables
 *   An associative array of variables to merge with defaults from the theme
379 380 381 382
 *   registry, pass to preprocess functions for modification, and finally, pass
 *   to the function or template implementing the theme hook. Alternatively,
 *   this can be a renderable array, in which case, its properties are mapped to
 *   variables expected by the theme hook implementations.
383
 *
384 385 386
 * @return string|false
 *   An HTML string representing the themed output or FALSE if the passed $hook
 *   is not implemented.
387
 *
388
 * @see drupal_render()
389
 * @see themeable
390 391
 * @see hook_theme()
 * @see template_preprocess()
Dries's avatar
 
Dries committed
392
 */
393
function _theme($hook, $variables = array()) {
394
  static $default_attributes;
395 396 397

  $module_handler = \Drupal::moduleHandler();

398 399
  // If called before all modules are loaded, we do not necessarily have a full
  // theme registry to work with, and therefore cannot process the theme
400
  // request properly. See also \Drupal\Core\Theme\Registry::get().
401
  if (!$module_handler->isLoaded() && !defined('MAINTENANCE_MODE')) {
402
    throw new Exception(t('_theme() may not be called until all modules are loaded.'));
403 404
  }

405 406
  /** @var \Drupal\Core\Utility\ThemeRegistry $theme_registry */
  $theme_registry = \Drupal::service('theme.registry')->getRuntime();
407

408 409
  // If an array of hook candidates were passed, use the first one that has an
  // implementation.
410 411
  if (is_array($hook)) {
    foreach ($hook as $candidate) {
412
      if ($theme_registry->has($candidate)) {
413 414 415 416 417
        break;
      }
    }
    $hook = $candidate;
  }
418 419 420
  // Save the original theme hook, so it can be supplied to theme variable
  // preprocess callbacks.
  $original_hook = $hook;
421

422 423
  // If there's no implementation, check for more generic fallbacks. If there's
  // still no implementation, log an error and return an empty string.
424
  if (!$theme_registry->has($hook)) {
425 426 427 428
    // Iteratively strip everything after the last '__' delimiter, until an
    // implementation is found.
    while ($pos = strrpos($hook, '__')) {
      $hook = substr($hook, 0, $pos);
429
      if ($theme_registry->has($hook)) {
430 431 432
        break;
      }
    }
433
    if (!$theme_registry->has($hook)) {
434 435 436
      // Only log a message when not trying theme suggestions ($hook being an
      // array).
      if (!isset($candidate)) {
437
        watchdog('theme', 'Theme hook %hook not found.', array('%hook' => $hook), WATCHDOG_WARNING);
438
      }
439
      // There is no theme implementation for the hook passed. Return FALSE so
440
      // the function calling _theme() can differentiate between a hook that
441 442
      // exists and renders an empty string and a hook that is not implemented.
      return FALSE;
443
    }
444 445
  }

446
  $info = $theme_registry->get($hook);
447 448 449
  global $theme_path;
  $temp = $theme_path;
  // point path_to_theme() to the currently used theme path:
450
  $theme_path = $info['theme path'];
Dries's avatar
 
Dries committed
451

452 453

  // If a renderable array is passed as $variables, then set $variables to
454
  // the arguments expected by the theme function.
455 456 457
  if (isset($variables['#theme']) || isset($variables['#theme_wrappers'])) {
    $element = $variables;
    $variables = array();
458 459
    if (isset($info['variables'])) {
      foreach (array_keys($info['variables']) as $name) {
460
        if (isset($element["#$name"]) || array_key_exists("#$name", $element)) {
461 462
          $variables[$name] = $element["#$name"];
        }
463 464
      }
    }
465 466
    else {
      $variables[$info['render element']] = $element;
467 468
      // Give a hint to render engines to prevent infinite recursion.
      $variables[$info['render element']]['#render_children'] = TRUE;
469
    }
470
  }
471

472
  // Merge in argument defaults.
473 474 475 476 477
  if (!empty($info['variables'])) {
    $variables += $info['variables'];
  }
  elseif (!empty($info['render element'])) {
    $variables += array($info['render element'] => array());
478
  }
479 480 481 482
  // Supply original caller info.
  $variables += array(
    'theme_hook_original' => $original_hook,
  );
483

484 485 486 487 488 489 490 491 492 493 494 495
  // Set base hook for later use. For example if '#theme' => 'node__article'
  // is called, we run hook_theme_suggestions_node_alter() rather than
  // hook_theme_suggestions_node__article_alter(), and also pass in the base
  // hook as the last parameter to the suggestions alter hooks.
  if (isset($info['base hook'])) {
    $base_theme_hook = $info['base hook'];
  }
  else {
    $base_theme_hook = $hook;
  }

  // Invoke hook_theme_suggestions_HOOK().
496
  $suggestions = $module_handler->invokeAll('theme_suggestions_' . $base_theme_hook, array($variables));
497
  // If _theme() was invoked with a direct theme suggestion like
498 499 500 501 502
  // '#theme' => 'node__article', add it to the suggestions array before
  // invoking suggestion alter hooks.
  if (isset($info['base hook'])) {
    $suggestions[] = $hook;
  }
503 504 505 506 507 508 509

  // Invoke hook_theme_suggestions_alter() and
  // hook_theme_suggestions_HOOK_alter().
  $hooks = array(
    'theme_suggestions',
    'theme_suggestions_' . $base_theme_hook,
  );
510
  $module_handler->alter($hooks, $suggestions, $variables, $base_theme_hook);
511 512

  // Check if each suggestion exists in the theme registry, and if so,
513 514
  // use it instead of the hook that _theme() was called with. For example, a
  // function may call _theme('node', ...), but a module can add
515 516 517
  // 'node__article' as a suggestion via hook_theme_suggestions_HOOK_alter(),
  // enabling a theme to have an alternate template file for article nodes.
  foreach (array_reverse($suggestions) as $suggestion) {
518 519
    if ($theme_registry->has($suggestion)) {
      $info = $theme_registry->get($suggestion);
520 521 522 523
      break;
    }
  }

524 525 526 527 528 529 530 531
  // Include a file if the theme function or variable preprocessor is held
  // elsewhere.
  if (!empty($info['includes'])) {
    foreach ($info['includes'] as $include_file) {
      include_once DRUPAL_ROOT . '/' . $include_file;
    }
  }

532
  // Invoke the variable preprocessors, if any.
533 534
  if (isset($info['base hook'])) {
    $base_hook = $info['base hook'];
535
    $base_hook_info = $theme_registry->get($base_hook);
536
    // Include files required by the base hook, since its variable preprocessors
537 538 539 540 541 542
    // might reside there.
    if (!empty($base_hook_info['includes'])) {
      foreach ($base_hook_info['includes'] as $include_file) {
        include_once DRUPAL_ROOT . '/' . $include_file;
      }
    }
543
    // Replace the preprocess functions with those from the base hook.
544
    if (isset($base_hook_info['preprocess functions'])) {
545 546 547 548
      // Set a variable for the 'theme_hook_suggestion'. This is used to
      // maintain backwards compatibility with template engines.
      $theme_hook_suggestion = $hook;
      $info['preprocess functions'] = $base_hook_info['preprocess functions'];
549 550
    }
  }
551 552 553 554
  if (isset($info['preprocess functions'])) {
    foreach ($info['preprocess functions'] as $preprocessor_function) {
      if (function_exists($preprocessor_function)) {
        $preprocessor_function($variables, $hook, $info);
555
      }
556 557
    }
  }
558

559
  // Generate the output using either a function or a template.
560
  $output = '';
561
  if (isset($info['function'])) {
562
    if (function_exists($info['function'])) {
563
      $output = $info['function']($variables);
Dries's avatar
 
Dries committed
564
    }
Dries's avatar
 
Dries committed
565
  }
566
  else {
567 568
    $render_function = 'twig_render_template';
    $extension = '.html.twig';
569

570
    // The theme engine may use a different extension and a different renderer.
571 572
    global $theme_engine;
    if (isset($theme_engine)) {
573
      if ($info['type'] != 'module') {
574 575
        if (function_exists($theme_engine . '_render_template')) {
          $render_function = $theme_engine . '_render_template';
576
        }
577
        $extension_function = $theme_engine . '_extension';
578 579 580 581 582 583
        if (function_exists($extension_function)) {
          $extension = $extension_function();
        }
      }
    }

584 585 586 587 588
    // In some cases, a template implementation may not have had
    // template_preprocess() run (for example, if the default implementation is
    // a function, but a template overrides that default implementation). In
    // these cases, a template should still be able to expect to have access to
    // the variables provided by template_preprocess(), so we add them here if
589 590 591 592 593
    // they don't already exist. We don't want the overhead of running
    // template_preprocess() twice, so we use the 'directory' variable to
    // determine if it has already run, which while not completely intuitive,
    // is reasonably safe, and allows us to save on the overhead of adding some
    // new variable to track that.
594 595
    if (!isset($variables['directory'])) {
      $default_template_variables = array();
596
      template_preprocess($default_template_variables, $hook, $info);
597 598
      $variables += $default_template_variables;
    }
599 600 601 602 603 604 605 606 607 608 609 610 611 612
    if (!isset($default_attributes)) {
      $default_attributes = new Attribute();
    }
    foreach (array('attributes', 'title_attributes', 'content_attributes') as $key) {
      if (isset($variables[$key]) && !($variables[$key] instanceof Attribute)) {
        if ($variables[$key]) {
          $variables[$key] = new Attribute($variables[$key]);
        }
        else {
          // Create empty attributes.
          $variables[$key] = clone $default_attributes;
        }
      }
    }
613

614 615 616 617
    // Render the output using the template file.
    $template_file = $info['template'] . $extension;
    if (isset($info['path'])) {
      $template_file = $info['path'] . '/' . $template_file;
618
    }
619 620 621 622 623 624 625 626 627 628
    // Add the theme suggestions to the variables array just before rendering
    // the template for backwards compatibility with template engines.
    $variables['theme_hook_suggestions'] = $suggestions;
    // For backwards compatibility, pass 'theme_hook_suggestion' on to the
    // template engine. This is only set when calling a direct suggestion like
    // '#theme' => 'menu_tree__shortcut_default' when the template exists in the
    // current theme.
    if (isset($theme_hook_suggestion)) {
      $variables['theme_hook_suggestion'] = $theme_hook_suggestion;
    }
629
    $output = $render_function($template_file, $variables);
Dries's avatar
 
Dries committed
630
  }
631

632 633
  // restore path_to_theme()
  $theme_path = $temp;
634
  return (string) $output;
635 636
}

Dries's avatar
 
Dries committed
637
/**
638 639 640 641 642 643 644 645
 * Returns the path to the current themed element.
 *
 * It can point to the active theme or the module handling a themed
 * implementation. For example, when invoked within the scope of a theming call
 * it will depend on where the theming function is handled. If implemented from
 * a module, it will point to the module. If implemented from the active theme,
 * it will point to the active theme. When called outside the scope of a
 * theming call, it will always point to the active theme.
Dries's avatar
 
Dries committed
646
 */
Dries's avatar
 
Dries committed
647
function path_to_theme() {
648
  global $theme_path;
Dries's avatar
 
Dries committed
649

650
  if (!isset($theme_path)) {
651
    drupal_theme_initialize();
652 653
  }

654
  return $theme_path;
655 656
}

657
/**
658
 * Allows themes and/or theme engines to discover overridden theme functions.
659 660 661 662 663 664
 *
 * @param $cache
 *   The existing cache of theme hooks to test against.
 * @param $prefixes
 *   An array of prefixes to test, in reverse order of importance.
 *
665
 * @return $implementations
666 667 668
 *   The functions found, suitable for returning from hook_theme;
 */
function drupal_find_theme_functions($cache, $prefixes) {
669
  $implementations = array();
670 671 672 673
  $functions = get_defined_functions();

  foreach ($cache as $hook => $info) {
    foreach ($prefixes as $prefix) {
674 675 676 677 678 679
      // Find theme functions that implement possible "suggestion" variants of
      // registered theme hooks and add those as new registered theme hooks.
      // The 'pattern' key defines a common prefix that all suggestions must
      // start with. The default is the name of the hook followed by '__'. An
      // 'base hook' key is added to each entry made for a found suggestion,
      // so that common functionality can be implemented for all suggestions of
680
      // the same base hook. To keep things simple, deep hierarchy of
681 682 683 684
      // suggestions is not supported: each suggestion's 'base hook' key
      // refers to a base hook, not to another suggestion, and all suggestions
      // are found using the base hook's pattern, not a pattern from an
      // intermediary suggestion.
685
      $pattern = isset($info['pattern']) ? $info['pattern'] : ($hook . '__');
686
      if (!isset($info['base hook']) && !empty($pattern)) {
687
        $matches = preg_grep('/^' . $prefix . '_' . $pattern . '/', $functions['user']);
688 689
        if ($matches) {
          foreach ($matches as $match) {
690
            $new_hook = substr($match, strlen($prefix) + 1);
691
            $arg_name = isset($info['variables']) ? 'variables' : 'render element';
692
            $implementations[$new_hook] = array(
693
              'function' => $match,
694
              $arg_name => $info[$arg_name],
695
              'base hook' => $hook,
696 697 698 699
            );
          }
        }
      }
700 701 702
      // Find theme functions that implement registered theme hooks and include
      // that in what is returned so that the registry knows that the theme has
      // this implementation.
703
      if (function_exists($prefix . '_' . $hook)) {
704
        $implementations[$hook] = array(
705
          'function' => $prefix . '_' . $hook,
706 707 708 709 710
        );
      }
    }
  }

711
  return $implementations;
712 713 714
}

/**
715
 * Allows themes and/or theme engines to easily discover overridden templates.
716 717 718 719 720 721 722 723 724
 *
 * @param $cache
 *   The existing cache of theme hooks to test against.
 * @param $extension
 *   The extension that these templates will have.
 * @param $path
 *   The path to search.
 */
function drupal_find_theme_templates($cache, $extension, $path) {
725
  $implementations = array();
726

727 728 729 730
  // Collect paths to all sub-themes grouped by base themes. These will be
  // used for filtering. This allows base themes to have sub-themes in its
  // folder hierarchy without affecting the base themes template discovery.
  $theme_paths = array();
731
  foreach (list_themes() as $theme_info) {
732
    if (!empty($theme_info->base_theme)) {
733
      $theme_paths[$theme_info->base_theme][$theme_info->getName()] = $theme_info->getPath();
734 735 736 737 738 739 740
    }
  }
  foreach ($theme_paths as $basetheme => $subthemes) {
    foreach ($subthemes as $subtheme => $subtheme_path) {
      if (isset($theme_paths[$subtheme])) {
        $theme_paths[$basetheme] = array_merge($theme_paths[$basetheme], $theme_paths[$subtheme]);
      }
741 742
    }
  }
743 744
  global $theme;
  $subtheme_paths = isset($theme_paths[$theme]) ? $theme_paths[$theme] : array();
745

746
  // Escape the periods in the extension.
747
  $regex = '/' . str_replace('.', '\.', $extension) . '$/';
748
  // Get a listing of all template files in the path to search.
749
  $files = file_scan_directory($path, $regex, array('key' => 'filename'));
750 751 752 753

  // Find templates that implement registered theme hooks and include that in
  // what is returned so that the registry knows that the theme has this
  // implementation.
754
  foreach ($files as $template => $file) {
755
    // Ignore sub-theme templates for the current theme.
756
    if (strpos($file->uri, str_replace($subtheme_paths, '', $file->uri)) !== 0) {
757 758
      continue;
    }
759 760
    // Remove the extension from the filename.
    $template = str_replace($extension, '', $template);
761 762 763 764
    // Transform - in filenames to _ to match function naming scheme
    // for the purposes of searching.
    $hook = strtr($template, '-', '_');
    if (isset($cache[$hook])) {
765
      $implementations[$hook] = array(
766
        'template' => $template,
767
        'path' => dirname($file->uri),
768 769
      );
    }
770 771 772 773

    // Match templates based on the 'template' filename.
    foreach ($cache as $hook => $info) {
      if (isset($info['template'])) {
774
        $template_candidates = array($info['template'], str_replace($info['theme path'] . '/templates/', '', $info['template']));
775 776 777 778 779 780 781 782
        if (in_array($template, $template_candidates)) {
          $implementations[$hook] = array(
            'template' => $template,
            'path' => dirname($file->uri),
          );
        }
      }
    }
783 784
  }

785
  // Find templates that implement possible "suggestion" variants of registered
786
  // theme hooks and add those as new registered theme hooks. See
787 788
  // drupal_find_theme_functions() for more information about suggestions and
  // the use of 'pattern' and 'base hook'.
789 790
  $patterns = array_keys($files);
  foreach ($cache as $hook => $info) {
791
    $pattern = isset($info['pattern']) ? $info['pattern'] : ($hook . '__');
792
    if (!isset($info['base hook']) && !empty($pattern)) {
793 794
      // Transform _ in pattern to - to match file naming scheme
      // for the purposes of searching.
795
      $pattern = strtr($pattern, '_', '-');
796

797
      $matches = preg_grep('/^' . $pattern . '/', $patterns);
798 799
      if ($matches) {
        foreach ($matches as $match) {
800
          $file = $match;
801 802
          // Remove the extension from the filename.
          $file = str_replace($extension, '', $file);
803 804
          // Put the underscores back in for the hook name and register this
          // pattern.
805
          $arg_name = isset($info['variables']) ? 'variables' : 'render element';
806
          $implementations[strtr($file, '-', '_')] = array(
807
            'template' => $file,
808
            'path' => dirname($files[$match]->uri),
809
            $arg_name => $info[$arg_name],
810
            'base hook' => $hook,
811 812 813 814 815
          );
        }
      }
    }
  }
816
  return $implementations;
817 818
}

Dries's avatar
 
Dries committed
819
/**
820
 * Retrieves a setting for the current theme or for a given theme.
Dries's avatar
 
Dries committed
821
 *
822 823
 * The final setting is obtained from the last value found in the following
 * sources:
824 825 826
 * - the default theme-specific settings defined in any base theme's .info.yml
 *   file
 * - the default theme-specific settings defined in the theme's .info.yml file
827 828 829 830
 * - the saved values from the global theme settings form
 * - the saved values from the theme's settings form
 * To only retrieve the default global theme setting, an empty string should be
 * given for $theme.
Dries's avatar
 
Dries committed
831 832
 *
 * @param $setting_name
833
 *   The name of the setting to be retrieved.
834
 * @param $theme
835 836
 *   The name of a given theme; defaults to the current theme.
 *
Dries's avatar
 
Dries committed
837 838 839
 * @return
 *   The value of the requested setting, NULL if the setting does not exist.
 */