Support LESS stylesheets in ResourceLoader
authorOri Livneh <ori@wikimedia.org>
Sun, 11 Aug 2013 16:40:20 +0000 (00:40 +0800)
committerOri Livneh <ori@wikimedia.org>
Mon, 23 Sep 2013 19:55:19 +0000 (12:55 -0700)
This patch adds support for the LESS stylesheet language to ResourceLoader.
LESS is a stylesheet language that compiles into CSS. The patch includes
lessphp, a LESS compiler implemented in PHP. The rationale for choosing LESS is
explained in a MediaWiki RFC which accompanies this patch, available at
<https://www.mediawiki.org/wiki/Requests_for_comment/LESS>.

LESS support is provided for ResourceLoader file modules. It is triggered by
the presence of the '.less' extension in stylesheet filenames. LESS files are
compiled by lessc, and the resultant CSS is subjected to the standard set of
transformations (CSSJanus & CSSMin). The immediate result of LESS compilation
is encoded as an array, which includes the list of LESS files that were
compiled and their mtimes. This array is cached. Cache invalidation is
performed by comparing the cached mtimes with the mtimes of the files on disk.
If the compiler itself throws an exception, ResourceLoader constructs a
compilation result which consists of the error message encoded as a CSS
comment. Failed compilation results are cached too, but with an expiration time
of five minutes. The expiration time is required because the full list of
referenced files is not known.

Three configuration variables configure the global environment for LESS
modules: $wgResourceLoaderLESSVars, $wgResourceLoaderLESSFunctions, and
$wgResourceLoaderLESSImportPaths. $wgResourceLoaderLESSVars maps variable names
to CSS values, specified as strings. Variables declared in this array are
available in all LESS files. $wgResourceLoaderLESSFunctions is similar, except
it maps custom function names to PHP callables. These functions can be called
from within LESS to transform values. Read more about custom functions at
<http://leafo.net/lessphp/docs/#custom_functions>. Finally,
$wgResourceLoaderLESSImportPaths specifies file system paths in addition to the
current module's path where the LESS compiler should look up files referenced
in @import statements.

The issue of handling of /* @embed */ and /* @noflip */ annotations is left
unresolved. Earlier versions of this patch included an @embed analog
implemented as a LESS custom function, but there was enough ambiguity about
whether the strategy it took was optimal to merit discussing it in a separate,
follow-up patch.

Bug: 40964
Change-Id: Id052a04dd2f76a1f4aef39fbd454bd67f5fd282f

12 files changed:
RELEASE-NOTES-1.22
includes/AutoLoader.php
includes/DefaultSettings.php
includes/libs/lessc.inc.php [new file with mode: 0644]
includes/resourceloader/ResourceLoaderFileModule.php
includes/resourceloader/ResourceLoaderModule.php
resources/mediawiki.less/mediawiki.mixins.less [new file with mode: 0644]
tests/phpunit/data/less/common/test.common.mixins.less [new file with mode: 0644]
tests/phpunit/data/less/module/dependency.less [new file with mode: 0644]
tests/phpunit/data/less/module/styles.css [new file with mode: 0644]
tests/phpunit/data/less/module/styles.less [new file with mode: 0644]
tests/phpunit/includes/ResourceLoaderTest.php

index 3112e26..44b1d36 100644 (file)
@@ -219,6 +219,19 @@ production.
 * Add a variable (wgRedactedFunctionArguments) to redact the values sent as certain function
   parameters from exception stack traces.
 * Added {{REVISIONSIZE}} variable to get the current size of a revision.
+* Add support for the LESS stylesheet language to ResourceLoader. LESS is a
+  stylesheet language that compiles into CSS. ResourceLoader file modules may
+  include LESS style files; ResourceLoader will compile these files into CSS
+  before sending them to the client.
+** The $wgResourceLoaderLESSVars configuration variable is an associative array
+   mapping variable names to string CSS values. These variables are considered
+   declared for all LESS files. Additional variables may be registered by
+   adding keys to the array.
+** $wgResourceLoaderLESSFunctions is an associative array of custom LESS
+   function names to PHP callables. See <http://leafo.net/lessphp/docs/#custom_functions>
+   for more details regarding custom functions.
+** $wgResourceLoaderLESSImportPaths is an array of file system paths. Files
+   referenced in LESS '@import' statements are looked up here first.
 
 === Bug fixes in 1.22 ===
 * Disable Special:PasswordReset when $wgEnableEmail is false. Previously one
index 604add3..daba73f 100644 (file)
@@ -704,6 +704,13 @@ $wgAutoloadLocalClasses = array(
        'JSToken' => 'includes/libs/jsminplus.php',
        'JSTokenizer' => 'includes/libs/jsminplus.php',
 
+       # includes/libs/lessphp
+       'lessc' => 'includes/libs/lessc.inc.php',
+       'lessc_parser' => 'includes/libs/lessc.inc.php',
+       'lessc_formatter_classic' => 'includes/libs/lessc.inc.php',
+       'lessc_formatter_compressed' => 'includes/libs/lessc.inc.php',
+       'lessc_formatter_lessjs' => 'includes/libs/lessc.inc.php',
+
        # includes/logging
        'DatabaseLogEntry' => 'includes/logging/LogEntry.php',
        'DeleteLogFormatter' => 'includes/logging/DeleteLogFormatter.php',
index 51c6c3d..c85623c 100644 (file)
@@ -3282,6 +3282,56 @@ $wgResourceLoaderValidateStaticJS = false;
  */
 $wgResourceLoaderExperimentalAsyncLoading = false;
 
+/**
+ * Global LESS variables. An associative array binding variable names to CSS
+ * string values.
+ *
+ * Because the hashed contents of this array are used to construct the cache key
+ * that ResourceLoader uses to look up LESS compilation results, updating this
+ * array can be used to deliberately invalidate the set of cached results.
+ *
+ * @par Example:
+ * @code
+ *   $wgResourceLoaderLESSVars = array(
+ *     'baseFontSize'  => '1em',
+ *     'smallFontSize' => '0.75em',
+ *     'WikimediaBlue' => '#006699',
+ *   );
+ * @endcode
+ * @since 1.22
+ */
+$wgResourceLoaderLESSVars = array();
+
+/**
+ * Custom LESS functions. An associative array mapping function name to PHP
+ * callable.
+ *
+ * Changes to LESS functions do not trigger cache invalidation. If you update
+ * the behavior of a LESS function and need to invalidate stale compilation
+ * results, you can touch one of values in $wgResourceLoaderLESSVars, as
+ * documented above.
+ *
+ * @since 1.22
+ */
+$wgResourceLoaderLESSFunctions = array();
+
+/**
+ * Default import paths for LESS modules. LESS files referenced in @import
+ * statements will be looked up here first, and relative to the importing file
+ * second. To avoid collisions, it's important for the LESS files in these
+ * directories to have a common, predictable file name prefix.
+ *
+ * Extensions need not (and should not) register paths in
+ * $wgResourceLoaderLESSImportPaths. The import path includes the path of the
+ * currently compiling LESS file, which allows each extension to freely import
+ * files from its own tree.
+ *
+ * @since 1.22
+ */
+$wgResourceLoaderLESSImportPaths = array(
+       "$IP/resources/mediawiki.less/",
+);
+
 /** @} */ # End of resource loader settings }
 
 /*************************************************************************//**
diff --git a/includes/libs/lessc.inc.php b/includes/libs/lessc.inc.php
new file mode 100644 (file)
index 0000000..a767edc
--- /dev/null
@@ -0,0 +1,3703 @@
+<?php
+
+/**
+ * lessphp v0.4.0
+ * http://leafo.net/lessphp
+ *
+ * LESS css compiler, adapted from http://lesscss.org
+ *
+ * For ease of distribution, lessphp 0.4.0 is under a dual license.
+ * You are free to pick which one suits your needs.
+ *
+ * MIT LICENSE
+ *
+ * Copyright (c) 2010-2012 Leaf Corcoran, http://leafo.net/lessphp
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * GPL VERSION 3
+ *
+ * Please refer to http://www.gnu.org/licenses/gpl-3.0.html for the full
+ * text of the GPL version 3
+ */
+
+
+/**
+ * The less compiler and parser.
+ *
+ * Converting LESS to CSS is a three stage process. The incoming file is parsed
+ * by `lessc_parser` into a syntax tree, then it is compiled into another tree
+ * representing the CSS structure by `lessc`. The CSS tree is fed into a
+ * formatter, like `lessc_formatter` which then outputs CSS as a string.
+ *
+ * During the first compile, all values are *reduced*, which means that their
+ * types are brought to the lowest form before being dump as strings. This
+ * handles math equations, variable dereferences, and the like.
+ *
+ * The `parse` function of `lessc` is the entry point.
+ *
+ * In summary:
+ *
+ * The `lessc` class creates an instance of the parser, feeds it LESS code,
+ * then transforms the resulting tree to a CSS tree. This class also holds the
+ * evaluation context, such as all available mixins and variables at any given
+ * time.
+ *
+ * The `lessc_parser` class is only concerned with parsing its input.
+ *
+ * The `lessc_formatter` takes a CSS tree, and dumps it to a formatted string,
+ * handling things like indentation.
+ */
+class lessc {
+       static public $VERSION = "v0.4.0";
+       static protected $TRUE = array("keyword", "true");
+       static protected $FALSE = array("keyword", "false");
+
+       protected $libFunctions = array();
+       protected $registeredVars = array();
+       protected $preserveComments = false;
+
+       public $vPrefix = '@'; // prefix of abstract properties
+       public $mPrefix = '$'; // prefix of abstract blocks
+       public $parentSelector = '&';
+
+       public $importDisabled = false;
+       public $importDir = '';
+
+       protected $numberPrecision = null;
+
+       protected $allParsedFiles = array();
+
+       // set to the parser that generated the current line when compiling
+       // so we know how to create error messages
+       protected $sourceParser = null;
+       protected $sourceLoc = null;
+
+       static public $defaultValue = array("keyword", "");
+
+       static protected $nextImportId = 0; // uniquely identify imports
+
+       // attempts to find the path of an import url, returns null for css files
+       protected function findImport($url) {
+               foreach ((array)$this->importDir as $dir) {
+                       $full = $dir.(substr($dir, -1) != '/' ? '/' : '').$url;
+                       if ($this->fileExists($file = $full.'.less') || $this->fileExists($file = $full)) {
+                               return $file;
+                       }
+               }
+
+               return null;
+       }
+
+       protected function fileExists($name) {
+               return is_file($name);
+       }
+
+       static public function compressList($items, $delim) {
+               if (!isset($items[1]) && isset($items[0])) return $items[0];
+               else return array('list', $delim, $items);
+       }
+
+       static public function preg_quote($what) {
+               return preg_quote($what, '/');
+       }
+
+       protected function tryImport($importPath, $parentBlock, $out) {
+               if ($importPath[0] == "function" && $importPath[1] == "url") {
+                       $importPath = $this->flattenList($importPath[2]);
+               }
+
+               $str = $this->coerceString($importPath);
+               if ($str === null) return false;
+
+               $url = $this->compileValue($this->lib_e($str));
+
+               // don't import if it ends in css
+               if (substr_compare($url, '.css', -4, 4) === 0) return false;
+
+               $realPath = $this->findImport($url);
+
+               if ($realPath === null) return false;
+
+               if ($this->importDisabled) {
+                       return array(false, "/* import disabled */");
+               }
+
+               if (isset($this->allParsedFiles[realpath($realPath)])) {
+                       return array(false, null);
+               }
+
+               $this->addParsedFile($realPath);
+               $parser = $this->makeParser($realPath);
+               $root = $parser->parse(file_get_contents($realPath));
+
+               // set the parents of all the block props
+               foreach ($root->props as $prop) {
+                       if ($prop[0] == "block") {
+                               $prop[1]->parent = $parentBlock;
+                       }
+               }
+
+               // copy mixins into scope, set their parents
+               // bring blocks from import into current block
+               // TODO: need to mark the source parser these came from this file
+               foreach ($root->children as $childName => $child) {
+                       if (isset($parentBlock->children[$childName])) {
+                               $parentBlock->children[$childName] = array_merge(
+                                       $parentBlock->children[$childName],
+                                       $child);
+                       } else {
+                               $parentBlock->children[$childName] = $child;
+                       }
+               }
+
+               $pi = pathinfo($realPath);
+               $dir = $pi["dirname"];
+
+               list($top, $bottom) = $this->sortProps($root->props, true);
+               $this->compileImportedProps($top, $parentBlock, $out, $parser, $dir);
+
+               return array(true, $bottom, $parser, $dir);
+       }
+
+       protected function compileImportedProps($props, $block, $out, $sourceParser, $importDir) {
+               $oldSourceParser = $this->sourceParser;
+
+               $oldImport = $this->importDir;
+
+               // TODO: this is because the importDir api is stupid
+               $this->importDir = (array)$this->importDir;
+               array_unshift($this->importDir, $importDir);
+
+               foreach ($props as $prop) {
+                       $this->compileProp($prop, $block, $out);
+               }
+
+               $this->importDir = $oldImport;
+               $this->sourceParser = $oldSourceParser;
+       }
+
+       /**
+        * Recursively compiles a block.
+        *
+        * A block is analogous to a CSS block in most cases. A single LESS document
+        * is encapsulated in a block when parsed, but it does not have parent tags
+        * so all of it's children appear on the root level when compiled.
+        *
+        * Blocks are made up of props and children.
+        *
+        * Props are property instructions, array tuples which describe an action
+        * to be taken, eg. write a property, set a variable, mixin a block.
+        *
+        * The children of a block are just all the blocks that are defined within.
+        * This is used to look up mixins when performing a mixin.
+        *
+        * Compiling the block involves pushing a fresh environment on the stack,
+        * and iterating through the props, compiling each one.
+        *
+        * See lessc::compileProp()
+        *
+        */
+       protected function compileBlock($block) {
+               switch ($block->type) {
+               case "root":
+                       $this->compileRoot($block);
+                       break;
+               case null:
+                       $this->compileCSSBlock($block);
+                       break;
+               case "media":
+                       $this->compileMedia($block);
+                       break;
+               case "directive":
+                       $name = "@" . $block->name;
+                       if (!empty($block->value)) {
+                               $name .= " " . $this->compileValue($this->reduce($block->value));
+                       }
+
+                       $this->compileNestedBlock($block, array($name));
+                       break;
+               default:
+                       $this->throwError("unknown block type: $block->type\n");
+               }
+       }
+
+       protected function compileCSSBlock($block) {
+               $env = $this->pushEnv();
+
+               $selectors = $this->compileSelectors($block->tags);
+               $env->selectors = $this->multiplySelectors($selectors);
+               $out = $this->makeOutputBlock(null, $env->selectors);
+
+               $this->scope->children[] = $out;
+               $this->compileProps($block, $out);
+
+               $block->scope = $env; // mixins carry scope with them!
+               $this->popEnv();
+       }
+
+       protected function compileMedia($media) {
+               $env = $this->pushEnv($media);
+               $parentScope = $this->mediaParent($this->scope);
+
+               $query = $this->compileMediaQuery($this->multiplyMedia($env));
+
+               $this->scope = $this->makeOutputBlock($media->type, array($query));
+               $parentScope->children[] = $this->scope;
+
+               $this->compileProps($media, $this->scope);
+
+               if (count($this->scope->lines) > 0) {
+                       $orphanSelelectors = $this->findClosestSelectors();
+                       if (!is_null($orphanSelelectors)) {
+                               $orphan = $this->makeOutputBlock(null, $orphanSelelectors);
+                               $orphan->lines = $this->scope->lines;
+                               array_unshift($this->scope->children, $orphan);
+                               $this->scope->lines = array();
+                       }
+               }
+
+               $this->scope = $this->scope->parent;
+               $this->popEnv();
+       }
+
+       protected function mediaParent($scope) {
+               while (!empty($scope->parent)) {
+                       if (!empty($scope->type) && $scope->type != "media") {
+                               break;
+                       }
+                       $scope = $scope->parent;
+               }
+
+               return $scope;
+       }
+
+       protected function compileNestedBlock($block, $selectors) {
+               $this->pushEnv($block);
+               $this->scope = $this->makeOutputBlock($block->type, $selectors);
+               $this->scope->parent->children[] = $this->scope;
+
+               $this->compileProps($block, $this->scope);
+
+               $this->scope = $this->scope->parent;
+               $this->popEnv();
+       }
+
+       protected function compileRoot($root) {
+               $this->pushEnv();
+               $this->scope = $this->makeOutputBlock($root->type);
+               $this->compileProps($root, $this->scope);
+               $this->popEnv();
+       }
+
+       protected function compileProps($block, $out) {
+               foreach ($this->sortProps($block->props) as $prop) {
+                       $this->compileProp($prop, $block, $out);
+               }
+
+               $out->lines = array_values(array_unique($out->lines));
+       }
+
+       protected function sortProps($props, $split = false) {
+               $vars = array();
+               $imports = array();
+               $other = array();
+
+               foreach ($props as $prop) {
+                       switch ($prop[0]) {
+                       case "assign":
+                               if (isset($prop[1][0]) && $prop[1][0] == $this->vPrefix) {
+                                       $vars[] = $prop;
+                               } else {
+                                       $other[] = $prop;
+                               }
+                               break;
+                       case "import":
+                               $id = self::$nextImportId++;
+                               $prop[] = $id;
+                               $imports[] = $prop;
+                               $other[] = array("import_mixin", $id);
+                               break;
+                       default:
+                               $other[] = $prop;
+                       }
+               }
+
+               if ($split) {
+                       return array(array_merge($vars, $imports), $other);
+               } else {
+                       return array_merge($vars, $imports, $other);
+               }
+       }
+
+       protected function compileMediaQuery($queries) {
+               $compiledQueries = array();
+               foreach ($queries as $query) {
+                       $parts = array();
+                       foreach ($query as $q) {
+                               switch ($q[0]) {
+                               case "mediaType":
+                                       $parts[] = implode(" ", array_slice($q, 1));
+                                       break;
+                               case "mediaExp":
+                                       if (isset($q[2])) {
+                                               $parts[] = "($q[1]: " .
+                                                       $this->compileValue($this->reduce($q[2])) . ")";
+                                       } else {
+                                               $parts[] = "($q[1])";
+                                       }
+                                       break;
+                               case "variable":
+                                       $parts[] = $this->compileValue($this->reduce($q));
+                               break;
+                               }
+                       }
+
+                       if (count($parts) > 0) {
+                               $compiledQueries[] =  implode(" and ", $parts);
+                       }
+               }
+
+               $out = "@media";
+               if (!empty($parts)) {
+                       $out .= " " .
+                               implode($this->formatter->selectorSeparator, $compiledQueries);
+               }
+               return $out;
+       }
+
+       protected function multiplyMedia($env, $childQueries = null) {
+               if (is_null($env) ||
+                       !empty($env->block->type) && $env->block->type != "media")
+               {
+                       return $childQueries;
+               }
+
+               // plain old block, skip
+               if (empty($env->block->type)) {
+                       return $this->multiplyMedia($env->parent, $childQueries);
+               }
+
+               $out = array();
+               $queries = $env->block->queries;
+               if (is_null($childQueries)) {
+                       $out = $queries;
+               } else {
+                       foreach ($queries as $parent) {
+                               foreach ($childQueries as $child) {
+                                       $out[] = array_merge($parent, $child);
+                               }
+                       }
+               }
+
+               return $this->multiplyMedia($env->parent, $out);
+       }
+
+       protected function expandParentSelectors(&$tag, $replace) {
+               $parts = explode("$&$", $tag);
+               $count = 0;
+               foreach ($parts as &$part) {
+                       $part = str_replace($this->parentSelector, $replace, $part, $c);
+                       $count += $c;
+               }
+               $tag = implode($this->parentSelector, $parts);
+               return $count;
+       }
+
+       protected function findClosestSelectors() {
+               $env = $this->env;
+               $selectors = null;
+               while ($env !== null) {
+                       if (isset($env->selectors)) {
+                               $selectors = $env->selectors;
+                               break;
+                       }
+                       $env = $env->parent;
+               }
+
+               return $selectors;
+       }
+
+
+       // multiply $selectors against the nearest selectors in env
+       protected function multiplySelectors($selectors) {
+               // find parent selectors
+
+               $parentSelectors = $this->findClosestSelectors();
+               if (is_null($parentSelectors)) {
+                       // kill parent reference in top level selector
+                       foreach ($selectors as &$s) {
+                               $this->expandParentSelectors($s, "");
+                       }
+
+                       return $selectors;
+               }
+
+               $out = array();
+               foreach ($parentSelectors as $parent) {
+                       foreach ($selectors as $child) {
+                               $count = $this->expandParentSelectors($child, $parent);
+
+                               // don't prepend the parent tag if & was used
+                               if ($count > 0) {
+                                       $out[] = trim($child);
+                               } else {
+                                       $out[] = trim($parent . ' ' . $child);
+                               }
+                       }
+               }
+
+               return $out;
+       }
+
+       // reduces selector expressions
+       protected function compileSelectors($selectors) {
+               $out = array();
+
+               foreach ($selectors as $s) {
+                       if (is_array($s)) {
+                               list(, $value) = $s;
+                               $out[] = trim($this->compileValue($this->reduce($value)));
+                       } else {
+                               $out[] = $s;
+                       }
+               }
+
+               return $out;
+       }
+
+       protected function eq($left, $right) {
+               return $left == $right;
+       }
+
+       protected function patternMatch($block, $orderedArgs, $keywordArgs) {
+               // match the guards if it has them
+               // any one of the groups must have all its guards pass for a match
+               if (!empty($block->guards)) {
+                       $groupPassed = false;
+                       foreach ($block->guards as $guardGroup) {
+                               foreach ($guardGroup as $guard) {
+                                       $this->pushEnv();
+                                       $this->zipSetArgs($block->args, $orderedArgs, $keywordArgs);
+
+                                       $negate = false;
+                                       if ($guard[0] == "negate") {
+                                               $guard = $guard[1];
+                                               $negate = true;
+                                       }
+
+                                       $passed = $this->reduce($guard) == self::$TRUE;
+                                       if ($negate) $passed = !$passed;
+
+                                       $this->popEnv();
+
+                                       if ($passed) {
+                                               $groupPassed = true;
+                                       } else {
+                                               $groupPassed = false;
+                                               break;
+                                       }
+                               }
+
+                               if ($groupPassed) break;
+                       }
+
+                       if (!$groupPassed) {
+                               return false;
+                       }
+               }
+
+               if (empty($block->args)) {
+                       return $block->isVararg || empty($orderedArgs) && empty($keywordArgs);
+               }
+
+               $remainingArgs = $block->args;
+               if ($keywordArgs) {
+                       $remainingArgs = array();
+                       foreach ($block->args as $arg) {
+                               if ($arg[0] == "arg" && isset($keywordArgs[$arg[1]])) {
+                                       continue;
+                               }
+
+                               $remainingArgs[] = $arg;
+                       }
+               }
+
+               $i = -1; // no args
+               // try to match by arity or by argument literal
+               foreach ($remainingArgs as $i => $arg) {
+                       switch ($arg[0]) {
+                       case "lit":
+                               if (empty($orderedArgs[$i]) || !$this->eq($arg[1], $orderedArgs[$i])) {
+                                       return false;
+                               }
+                               break;
+                       case "arg":
+                               // no arg and no default value
+                               if (!isset($orderedArgs[$i]) && !isset($arg[2])) {
+                                       return false;
+                               }
+                               break;
+                       case "rest":
+                               $i--; // rest can be empty
+                               break 2;
+                       }
+               }
+
+               if ($block->isVararg) {
+                       return true; // not having enough is handled above
+               } else {
+                       $numMatched = $i + 1;
+                       // greater than becuase default values always match
+                       return $numMatched >= count($orderedArgs);
+               }
+       }
+
+       protected function patternMatchAll($blocks, $orderedArgs, $keywordArgs, $skip=array()) {
+               $matches = null;
+               foreach ($blocks as $block) {
+                       // skip seen blocks that don't have arguments
+                       if (isset($skip[$block->id]) && !isset($block->args)) {
+                               continue;
+                       }
+
+                       if ($this->patternMatch($block, $orderedArgs, $keywordArgs)) {
+                               $matches[] = $block;
+                       }
+               }
+
+               return $matches;
+       }
+
+       // attempt to find blocks matched by path and args
+       protected function findBlocks($searchIn, $path, $orderedArgs, $keywordArgs, $seen=array()) {
+               if ($searchIn == null) return null;
+               if (isset($seen[$searchIn->id])) return null;
+               $seen[$searchIn->id] = true;
+
+               $name = $path[0];
+
+               if (isset($searchIn->children[$name])) {
+                       $blocks = $searchIn->children[$name];
+                       if (count($path) == 1) {
+                               $matches = $this->patternMatchAll($blocks, $orderedArgs, $keywordArgs, $seen);
+                               if (!empty($matches)) {
+                                       // This will return all blocks that match in the closest
+                                       // scope that has any matching block, like lessjs
+                                       return $matches;
+                               }
+                       } else {
+                               $matches = array();
+                               foreach ($blocks as $subBlock) {
+                                       $subMatches = $this->findBlocks($subBlock,
+                                               array_slice($path, 1), $orderedArgs, $keywordArgs, $seen);
+
+                                       if (!is_null($subMatches)) {
+                                               foreach ($subMatches as $sm) {
+                                                       $matches[] = $sm;
+                                               }
+                                       }
+                               }
+
+                               return count($matches) > 0 ? $matches : null;
+                       }
+               }
+               if ($searchIn->parent === $searchIn) return null;
+               return $this->findBlocks($searchIn->parent, $path, $orderedArgs, $keywordArgs, $seen);
+       }
+
+       // sets all argument names in $args to either the default value
+       // or the one passed in through $values
+       protected function zipSetArgs($args, $orderedValues, $keywordValues) {
+               $assignedValues = array();
+
+               $i = 0;
+               foreach ($args as  $a) {
+                       if ($a[0] == "arg") {
+                               if (isset($keywordValues[$a[1]])) {
+                                       // has keyword arg
+                                       $value = $keywordValues[$a[1]];
+                               } elseif (isset($orderedValues[$i])) {
+                                       // has ordered arg
+                                       $value = $orderedValues[$i];
+                                       $i++;
+                               } elseif (isset($a[2])) {
+                                       // has default value
+                                       $value = $a[2];
+                               } else {
+                                       $this->throwError("Failed to assign arg " . $a[1]);
+                                       $value = null; // :(
+                               }
+
+                               $value = $this->reduce($value);
+                               $this->set($a[1], $value);
+                               $assignedValues[] = $value;
+                       } else {
+                               // a lit
+                               $i++;
+                       }
+               }
+
+               // check for a rest
+               $last = end($args);
+               if ($last[0] == "rest") {
+                       $rest = array_slice($orderedValues, count($args) - 1);
+                       $this->set($last[1], $this->reduce(array("list", " ", $rest)));
+               }
+
+               // wow is this the only true use of PHP's + operator for arrays?
+               $this->env->arguments = $assignedValues + $orderedValues;
+       }
+
+       // compile a prop and update $lines or $blocks appropriately
+       protected function compileProp($prop, $block, $out) {
+               // set error position context
+               $this->sourceLoc = isset($prop[-1]) ? $prop[-1] : -1;
+
+               switch ($prop[0]) {
+               case 'assign':
+                       list(, $name, $value) = $prop;
+                       if ($name[0] == $this->vPrefix) {
+                               $this->set($name, $value);
+                       } else {
+                               $out->lines[] = $this->formatter->property($name,
+                                               $this->compileValue($this->reduce($value)));
+                       }
+                       break;
+               case 'block':
+                       list(, $child) = $prop;
+                       $this->compileBlock($child);
+                       break;
+               case 'mixin':
+                       list(, $path, $args, $suffix) = $prop;
+
+                       $orderedArgs = array();
+                       $keywordArgs = array();
+                       foreach ((array)$args as $arg) {
+                               $argval = null;
+                               switch ($arg[0]) {
+                               case "arg":
+                                       if (!isset($arg[2])) {
+                                               $orderedArgs[] = $this->reduce(array("variable", $arg[1]));
+                                       } else {
+                                               $keywordArgs[$arg[1]] = $this->reduce($arg[2]);
+                                       }
+                                       break;
+
+                               case "lit":
+                                       $orderedArgs[] = $this->reduce($arg[1]);
+                                       break;
+                               default:
+                                       $this->throwError("Unknown arg type: " . $arg[0]);
+                               }
+                       }
+
+                       $mixins = $this->findBlocks($block, $path, $orderedArgs, $keywordArgs);
+
+                       if ($mixins === null) {
+                               // fwrite(STDERR,"failed to find block: ".implode(" > ", $path)."\n");
+                               break; // throw error here??
+                       }
+
+                       foreach ($mixins as $mixin) {
+                               if ($mixin === $block && !$orderedArgs) {
+                                       continue;
+                               }
+
+                               $haveScope = false;
+                               if (isset($mixin->parent->scope)) {
+                                       $haveScope = true;
+                                       $mixinParentEnv = $this->pushEnv();
+                                       $mixinParentEnv->storeParent = $mixin->parent->scope;
+                               }
+
+                               $haveArgs = false;
+                               if (isset($mixin->args)) {
+                                       $haveArgs = true;
+                                       $this->pushEnv();
+                                       $this->zipSetArgs($mixin->args, $orderedArgs, $keywordArgs);
+                               }
+
+                               $oldParent = $mixin->parent;
+                               if ($mixin != $block) $mixin->parent = $block;
+
+                               foreach ($this->sortProps($mixin->props) as $subProp) {
+                                       if ($suffix !== null &&
+                                               $subProp[0] == "assign" &&
+                                               is_string($subProp[1]) &&
+                                               $subProp[1]{0} != $this->vPrefix)
+                                       {
+                                               $subProp[2] = array(
+                                                       'list', ' ',
+                                                       array($subProp[2], array('keyword', $suffix))
+                                               );
+                                       }
+
+                                       $this->compileProp($subProp, $mixin, $out);
+                               }
+
+                               $mixin->parent = $oldParent;
+
+                               if ($haveArgs) $this->popEnv();
+                               if ($haveScope) $this->popEnv();
+                       }
+
+                       break;
+               case 'raw':
+                       $out->lines[] = $prop[1];
+                       break;
+               case "directive":
+                       list(, $name, $value) = $prop;
+                       $out->lines[] = "@$name " . $this->compileValue($this->reduce($value)).';';
+                       break;
+               case "comment":
+                       $out->lines[] = $prop[1];
+                       break;
+               case "import";
+                       list(, $importPath, $importId) = $prop;
+                       $importPath = $this->reduce($importPath);
+
+                       if (!isset($this->env->imports)) {
+                               $this->env->imports = array();
+                       }
+
+                       $result = $this->tryImport($importPath, $block, $out);
+
+                       $this->env->imports[$importId] = $result === false ?
+                               array(false, "@import " . $this->compileValue($importPath).";") :
+                               $result;
+
+                       break;
+               case "import_mixin":
+                       list(,$importId) = $prop;
+                       $import = $this->env->imports[$importId];
+                       if ($import[0] === false) {
+                               if (isset($import[1])) {
+                                       $out->lines[] = $import[1];
+                               }
+                       } else {
+                               list(, $bottom, $parser, $importDir) = $import;
+                               $this->compileImportedProps($bottom, $block, $out, $parser, $importDir);
+                       }
+
+                       break;
+               default:
+                       $this->throwError("unknown op: {$prop[0]}\n");
+               }
+       }
+
+
+       /**
+        * Compiles a primitive value into a CSS property value.
+        *
+        * Values in lessphp are typed by being wrapped in arrays, their format is
+        * typically:
+        *
+        *     array(type, contents [, additional_contents]*)
+        *
+        * The input is expected to be reduced. This function will not work on
+        * things like expressions and variables.
+        */
+       protected function compileValue($value) {
+               switch ($value[0]) {
+               case 'list':
+                       // [1] - delimiter
+                       // [2] - array of values
+                       return implode($value[1], array_map(array($this, 'compileValue'), $value[2]));
+               case 'raw_color':
+                       if (!empty($this->formatter->compressColors)) {
+                               return $this->compileValue($this->coerceColor($value));
+                       }
+                       return $value[1];
+               case 'keyword':
+                       // [1] - the keyword
+                       return $value[1];
+               case 'number':
+                       list(, $num, $unit) = $value;
+                       // [1] - the number
+                       // [2] - the unit
+                       if ($this->numberPrecision !== null) {
+                               $num = round($num, $this->numberPrecision);
+                       }
+                       return $num . $unit;
+               case 'string':
+                       // [1] - contents of string (includes quotes)
+                       list(, $delim, $content) = $value;
+                       foreach ($content as &$part) {
+                               if (is_array($part)) {
+                                       $part = $this->compileValue($part);
+                               }
+                       }
+                       return $delim . implode($content) . $delim;
+               case 'color':
+                       // [1] - red component (either number or a %)
+                       // [2] - green component
+                       // [3] - blue component
+                       // [4] - optional alpha component
+                       list(, $r, $g, $b) = $value;
+                       $r = round($r);
+                       $g = round($g);
+                       $b = round($b);
+
+                       if (count($value) == 5 && $value[4] != 1) { // rgba
+                               return 'rgba('.$r.','.$g.','.$b.','.$value[4].')';
+                       }
+
+                       $h = sprintf("#%02x%02x%02x", $r, $g, $b);
+
+                       if (!empty($this->formatter->compressColors)) {
+                               // Converting hex color to short notation (e.g. #003399 to #039)
+                               if ($h[1] === $h[2] && $h[3] === $h[4] && $h[5] === $h[6]) {
+                                       $h = '#' . $h[1] . $h[3] . $h[5];
+                               }
+                       }
+
+                       return $h;
+
+               case 'function':
+                       list(, $name, $args) = $value;
+                       return $name.'('.$this->compileValue($args).')';
+               default: // assumed to be unit
+                       $this->throwError("unknown value type: $value[0]");
+               }
+       }
+
+       protected function lib_pow($args) {
+               list($base, $exp) = $this->assertArgs($args, 2, "pow");
+               return pow($this->assertNumber($base), $this->assertNumber($exp));
+       }
+
+       protected function lib_pi() {
+               return pi();
+       }
+
+       protected function lib_mod($args) {
+               list($a, $b) = $this->assertArgs($args, 2, "mod");
+               return $this->assertNumber($a) % $this->assertNumber($b);
+       }
+
+       protected function lib_tan($num) {
+               return tan($this->assertNumber($num));
+       }
+
+       protected function lib_sin($num) {
+               return sin($this->assertNumber($num));
+       }
+
+       protected function lib_cos($num) {
+               return cos($this->assertNumber($num));
+       }
+
+       protected function lib_atan($num) {
+               $num = atan($this->assertNumber($num));
+               return array("number", $num, "rad");
+       }
+
+       protected function lib_asin($num) {
+               $num = asin($this->assertNumber($num));
+               return array("number", $num, "rad");
+       }
+
+       protected function lib_acos($num) {
+               $num = acos($this->assertNumber($num));
+               return array("number", $num, "rad");
+       }
+
+       protected function lib_sqrt($num) {
+               return sqrt($this->assertNumber($num));
+       }
+
+       protected function lib_extract($value) {
+               list($list, $idx) = $this->assertArgs($value, 2, "extract");
+               $idx = $this->assertNumber($idx);
+               // 1 indexed
+               if ($list[0] == "list" && isset($list[2][$idx - 1])) {
+                       return $list[2][$idx - 1];
+               }
+       }
+
+       protected function lib_isnumber($value) {
+               return $this->toBool($value[0] == "number");
+       }
+
+       protected function lib_isstring($value) {
+               return $this->toBool($value[0] == "string");
+       }
+
+       protected function lib_iscolor($value) {
+               return $this->toBool($this->coerceColor($value));
+       }
+
+       protected function lib_iskeyword($value) {
+               return $this->toBool($value[0] == "keyword");
+       }
+
+       protected function lib_ispixel($value) {
+               return $this->toBool($value[0] == "number" && $value[2] == "px");
+       }
+
+       protected function lib_ispercentage($value) {
+               return $this->toBool($value[0] == "number" && $value[2] == "%");
+       }
+
+       protected function lib_isem($value) {
+               return $this->toBool($value[0] == "number" && $value[2] == "em");
+       }
+
+       protected function lib_isrem($value) {
+               return $this->toBool($value[0] == "number" && $value[2] == "rem");
+       }
+
+       protected function lib_rgbahex($color) {
+               $color = $this->coerceColor($color);
+               if (is_null($color))
+                       $this->throwError("color expected for rgbahex");
+
+               return sprintf("#%02x%02x%02x%02x",
+                       isset($color[4]) ? $color[4]*255 : 255,
+                       $color[1],$color[2], $color[3]);
+       }
+
+       protected function lib_argb($color){
+               return $this->lib_rgbahex($color);
+       }
+
+       // utility func to unquote a string
+       protected function lib_e($arg) {
+               switch ($arg[0]) {
+                       case "list":
+                               $items = $arg[2];
+                               if (isset($items[0])) {
+                                       return $this->lib_e($items[0]);
+                               }
+                               return self::$defaultValue;
+                       case "string":
+                               $arg[1] = "";
+                               return $arg;
+                       case "keyword":
+                               return $arg;
+                       default:
+                               return array("keyword", $this->compileValue($arg));
+               }
+       }
+
+       protected function lib__sprintf($args) {
+               if ($args[0] != "list") return $args;
+               $values = $args[2];
+               $string = array_shift($values);
+               $template = $this->compileValue($this->lib_e($string));
+
+               $i = 0;
+               if (preg_match_all('/%[dsa]/', $template, $m)) {
+                       foreach ($m[0] as $match) {
+                               $val = isset($values[$i]) ?
+                                       $this->reduce($values[$i]) : array('keyword', '');
+
+                               // lessjs compat, renders fully expanded color, not raw color
+                               if ($color = $this->coerceColor($val)) {
+                                       $val = $color;
+                               }
+
+                               $i++;
+                               $rep = $this->compileValue($this->lib_e($val));
+                               $template = preg_replace('/'.self::preg_quote($match).'/',
+                                       $rep, $template, 1);
+                       }
+               }
+
+               $d = $string[0] == "string" ? $string[1] : '"';
+               return array("string", $d, array($template));
+       }
+
+       protected function lib_floor($arg) {
+               $value = $this->assertNumber($arg);
+               return array("number", floor($value), $arg[2]);
+       }
+
+       protected function lib_ceil($arg) {
+               $value = $this->assertNumber($arg);
+               return array("number", ceil($value), $arg[2]);
+       }
+
+       protected function lib_round($arg) {
+               $value = $this->assertNumber($arg);
+               return array("number", round($value), $arg[2]);
+       }
+
+       protected function lib_unit($arg) {
+               if ($arg[0] == "list") {
+                       list($number, $newUnit) = $arg[2];
+                       return array("number", $this->assertNumber($number),
+                               $this->compileValue($this->lib_e($newUnit)));
+               } else {
+                       return array("number", $this->assertNumber($arg), "");
+               }
+       }
+
+       /**
+        * Helper function to get arguments for color manipulation functions.
+        * takes a list that contains a color like thing and a percentage
+        */
+       protected function colorArgs($args) {
+               if ($args[0] != 'list' || count($args[2]) < 2) {
+                       return array(array('color', 0, 0, 0), 0);
+               }
+               list($color, $delta) = $args[2];
+               $color = $this->assertColor($color);
+               $delta = floatval($delta[1]);
+
+               return array($color, $delta);
+       }
+
+       protected function lib_darken($args) {
+               list($color, $delta) = $this->colorArgs($args);
+
+               $hsl = $this->toHSL($color);
+               $hsl[3] = $this->clamp($hsl[3] - $delta, 100);
+               return $this->toRGB($hsl);
+       }
+
+       protected function lib_lighten($args) {
+               list($color, $delta) = $this->colorArgs($args);
+
+               $hsl = $this->toHSL($color);
+               $hsl[3] = $this->clamp($hsl[3] + $delta, 100);
+               return $this->toRGB($hsl);
+       }
+
+       protected function lib_saturate($args) {
+               list($color, $delta) = $this->colorArgs($args);
+
+               $hsl = $this->toHSL($color);
+               $hsl[2] = $this->clamp($hsl[2] + $delta, 100);
+               return $this->toRGB($hsl);
+       }
+
+       protected function lib_desaturate($args) {
+               list($color, $delta) = $this->colorArgs($args);
+
+               $hsl = $this->toHSL($color);
+               $hsl[2] = $this->clamp($hsl[2] - $delta, 100);
+               return $this->toRGB($hsl);
+       }
+
+       protected function lib_spin($args) {
+               list($color, $delta) = $this->colorArgs($args);
+
+               $hsl = $this->toHSL($color);
+
+               $hsl[1] = $hsl[1] + $delta % 360;
+               if ($hsl[1] < 0) $hsl[1] += 360;
+
+               return $this->toRGB($hsl);
+       }
+
+       protected function lib_fadeout($args) {
+               list($color, $delta) = $this->colorArgs($args);
+               $color[4] = $this->clamp((isset($color[4]) ? $color[4] : 1) - $delta/100);
+               return $color;
+       }
+
+       protected function lib_fadein($args) {
+               list($color, $delta) = $this->colorArgs($args);
+               $color[4] = $this->clamp((isset($color[4]) ? $color[4] : 1) + $delta/100);
+               return $color;
+       }
+
+       protected function lib_hue($color) {
+               $hsl = $this->toHSL($this->assertColor($color));
+               return round($hsl[1]);
+       }
+
+       protected function lib_saturation($color) {
+               $hsl = $this->toHSL($this->assertColor($color));
+               return round($hsl[2]);
+       }
+
+       protected function lib_lightness($color) {
+               $hsl = $this->toHSL($this->assertColor($color));
+               return round($hsl[3]);
+       }
+
+       // get the alpha of a color
+       // defaults to 1 for non-colors or colors without an alpha
+       protected function lib_alpha($value) {
+               if (!is_null($color = $this->coerceColor($value))) {
+                       return isset($color[4]) ? $color[4] : 1;
+               }
+       }
+
+       // set the alpha of the color
+       protected function lib_fade($args) {
+               list($color, $alpha) = $this->colorArgs($args);
+               $color[4] = $this->clamp($alpha / 100.0);
+               return $color;
+       }
+
+       protected function lib_percentage($arg) {
+               $num = $this->assertNumber($arg);
+               return array("number", $num*100, "%");
+       }
+
+       // mixes two colors by weight
+       // mix(@color1, @color2, [@weight: 50%]);
+       // http://sass-lang.com/docs/yardoc/Sass/Script/Functions.html#mix-instance_method
+       protected function lib_mix($args) {
+               if ($args[0] != "list" || count($args[2]) < 2)
+                       $this->throwError("mix expects (color1, color2, weight)");
+
+               list($first, $second) = $args[2];
+               $first = $this->assertColor($first);
+               $second = $this->assertColor($second);
+
+               $first_a = $this->lib_alpha($first);
+               $second_a = $this->lib_alpha($second);
+
+               if (isset($args[2][2])) {
+                       $weight = $args[2][2][1] / 100.0;
+               } else {
+                       $weight = 0.5;
+               }
+
+               $w = $weight * 2 - 1;
+               $a = $first_a - $second_a;
+
+               $w1 = (($w * $a == -1 ? $w : ($w + $a)/(1 + $w * $a)) + 1) / 2.0;
+               $w2 = 1.0 - $w1;
+
+               $new = array('color',
+                       $w1 * $first[1] + $w2 * $second[1],
+                       $w1 * $first[2] + $w2 * $second[2],
+                       $w1 * $first[3] + $w2 * $second[3],
+               );
+
+               if ($first_a != 1.0 || $second_a != 1.0) {
+                       $new[] = $first_a * $weight + $second_a * ($weight - 1);
+               }
+
+               return $this->fixColor($new);
+       }
+
+       protected function lib_contrast($args) {
+               if ($args[0] != 'list' || count($args[2]) < 3) {
+                       return array(array('color', 0, 0, 0), 0);
+               }
+
+               list($inputColor, $darkColor, $lightColor) = $args[2];
+
+               $inputColor = $this->assertColor($inputColor);
+               $darkColor = $this->assertColor($darkColor);
+               $lightColor = $this->assertColor($lightColor);
+               $hsl = $this->toHSL($inputColor);
+
+               if ($hsl[3] > 50) {
+                       return $darkColor;
+               }
+
+               return $lightColor;
+       }
+
+       protected function assertColor($value, $error = "expected color value") {
+               $color = $this->coerceColor($value);
+               if (is_null($color)) $this->throwError($error);
+               return $color;
+       }
+
+       protected function assertNumber($value, $error = "expecting number") {
+               if ($value[0] == "number") return $value[1];
+               $this->throwError($error);
+       }
+
+       protected function assertArgs($value, $expectedArgs, $name="") {
+               if ($expectedArgs == 1) {
+                       return $value;
+               } else {
+                       if ($value[0] !== "list" || $value[1] != ",") $this->throwError("expecting list");
+                       $values = $value[2];
+                       $numValues = count($values);
+                       if ($expectedArgs != $numValues) {
+                               if ($name) {
+                                       $name = $name . ": ";
+                               }
+
+                               $this->throwError("${name}expecting $expectedArgs arguments, got $numValues");
+                       }
+
+                       return $values;
+               }
+       }
+
+       protected function toHSL($color) {
+               if ($color[0] == 'hsl') return $color;
+
+               $r = $color[1] / 255;
+               $g = $color[2] / 255;
+               $b = $color[3] / 255;
+
+               $min = min($r, $g, $b);
+               $max = max($r, $g, $b);
+
+               $L = ($min + $max) / 2;
+               if ($min == $max) {
+                       $S = $H = 0;
+               } else {
+                       if ($L < 0.5)
+                               $S = ($max - $min)/($max + $min);
+                       else
+                               $S = ($max - $min)/(2.0 - $max - $min);
+
+                       if ($r == $max) $H = ($g - $b)/($max - $min);
+                       elseif ($g == $max) $H = 2.0 + ($b - $r)/($max - $min);
+                       elseif ($b == $max) $H = 4.0 + ($r - $g)/($max - $min);
+
+               }
+
+               $out = array('hsl',
+                       ($H < 0 ? $H + 6 : $H)*60,
+                       $S*100,
+                       $L*100,
+               );
+
+               if (count($color) > 4) $out[] = $color[4]; // copy alpha
+               return $out;
+       }
+
+       protected function toRGB_helper($comp, $temp1, $temp2) {
+               if ($comp < 0) $comp += 1.0;
+               elseif ($comp > 1) $comp -= 1.0;
+
+               if (6 * $comp < 1) return $temp1 + ($temp2 - $temp1) * 6 * $comp;
+               if (2 * $comp < 1) return $temp2;
+               if (3 * $comp < 2) return $temp1 + ($temp2 - $temp1)*((2/3) - $comp) * 6;
+
+               return $temp1;
+       }
+
+       /**
+        * Converts a hsl array into a color value in rgb.
+        * Expects H to be in range of 0 to 360, S and L in 0 to 100
+        */
+       protected function toRGB($color) {
+               if ($color[0] == 'color') return $color;
+
+               $H = $color[1] / 360;
+               $S = $color[2] / 100;
+               $L = $color[3] / 100;
+
+               if ($S == 0) {
+                       $r = $g = $b = $L;
+               } else {
+                       $temp2 = $L < 0.5 ?
+                               $L*(1.0 + $S) :
+                               $L + $S - $L * $S;
+
+                       $temp1 = 2.0 * $L - $temp2;
+
+                       $r = $this->toRGB_helper($H + 1/3, $temp1, $temp2);
+                       $g = $this->toRGB_helper($H, $temp1, $temp2);
+                       $b = $this->toRGB_helper($H - 1/3, $temp1, $temp2);
+               }
+
+               // $out = array('color', round($r*255), round($g*255), round($b*255));
+               $out = array('color', $r*255, $g*255, $b*255);
+               if (count($color) > 4) $out[] = $color[4]; // copy alpha
+               return $out;
+       }
+
+       protected function clamp($v, $max = 1, $min = 0) {
+               return min($max, max($min, $v));
+       }
+
+       /**
+        * Convert the rgb, rgba, hsl color literals of function type
+        * as returned by the parser into values of color type.
+        */
+       protected function funcToColor($func) {
+               $fname = $func[1];
+               if ($func[2][0] != 'list') return false; // need a list of arguments
+               $rawComponents = $func[2][2];
+
+               if ($fname == 'hsl' || $fname == 'hsla') {
+                       $hsl = array('hsl');
+                       $i = 0;
+                       foreach ($rawComponents as $c) {
+                               $val = $this->reduce($c);
+                               $val = isset($val[1]) ? floatval($val[1]) : 0;
+
+                               if ($i == 0) $clamp = 360;
+                               elseif ($i < 3) $clamp = 100;
+                               else $clamp = 1;
+
+                               $hsl[] = $this->clamp($val, $clamp);
+                               $i++;
+                       }
+
+                       while (count($hsl) < 4) $hsl[] = 0;
+                       return $this->toRGB($hsl);
+
+               } elseif ($fname == 'rgb' || $fname == 'rgba') {
+                       $components = array();
+                       $i = 1;
+                       foreach ($rawComponents as $c) {
+                               $c = $this->reduce($c);
+                               if ($i < 4) {
+                                       if ($c[0] == "number" && $c[2] == "%") {
+                                               $components[] = 255 * ($c[1] / 100);
+                                       } else {
+                                               $components[] = floatval($c[1]);
+                                       }
+                               } elseif ($i == 4) {
+                                       if ($c[0] == "number" && $c[2] == "%") {
+                                               $components[] = 1.0 * ($c[1] / 100);
+                                       } else {
+                                               $components[] = floatval($c[1]);
+                                       }
+                               } else break;
+
+                               $i++;
+                       }
+                       while (count($components) < 3) $components[] = 0;
+                       array_unshift($components, 'color');
+                       return $this->fixColor($components);
+               }
+
+               return false;
+       }
+
+       protected function reduce($value, $forExpression = false) {
+               switch ($value[0]) {
+               case "interpolate":
+                       $reduced = $this->reduce($value[1]);
+                       $var = $this->compileValue($reduced);
+                       $res = $this->reduce(array("variable", $this->vPrefix . $var));
+
+                       if ($res[0] == "raw_color") {
+                               $res = $this->coerceColor($res);
+                       }
+
+                       if (empty($value[2])) $res = $this->lib_e($res);
+
+                       return $res;
+               case "variable":
+                       $key = $value[1];
+                       if (is_array($key)) {
+                               $key = $this->reduce($key);
+                               $key = $this->vPrefix . $this->compileValue($this->lib_e($key));
+                       }
+
+                       $seen =& $this->env->seenNames;
+
+                       if (!empty($seen[$key])) {
+                               $this->throwError("infinite loop detected: $key");
+                       }
+
+                       $seen[$key] = true;
+                       $out = $this->reduce($this->get($key, self::$defaultValue));
+                       $seen[$key] = false;
+                       return $out;
+               case "list":
+                       foreach ($value[2] as &$item) {
+                               $item = $this->reduce($item, $forExpression);
+                       }
+                       return $value;
+               case "expression":
+                       return $this->evaluate($value);
+               case "string":
+                       foreach ($value[2] as &$part) {
+                               if (is_array($part)) {
+                                       $strip = $part[0] == "variable";
+                                       $part = $this->reduce($part);
+                                       if ($strip) $part = $this->lib_e($part);
+                               }
+                       }
+                       return $value;
+               case "escape":
+                       list(,$inner) = $value;
+                       return $this->lib_e($this->reduce($inner));
+               case "function":
+                       $color = $this->funcToColor($value);
+                       if ($color) return $color;
+
+                       list(, $name, $args) = $value;
+                       if ($name == "%") $name = "_sprintf";
+                       $f = isset($this->libFunctions[$name]) ?
+                               $this->libFunctions[$name] : array($this, 'lib_'.$name);
+
+                       if (is_callable($f)) {
+                               if ($args[0] == 'list')
+                                       $args = self::compressList($args[2], $args[1]);
+
+                               $ret = call_user_func($f, $this->reduce($args, true), $this);
+
+                               if (is_null($ret)) {
+                                       return array("string", "", array(
+                                               $name, "(", $args, ")"
+                                       ));
+                               }
+
+                               // convert to a typed value if the result is a php primitive
+                               if (is_numeric($ret)) $ret = array('number', $ret, "");
+                               elseif (!is_array($ret)) $ret = array('keyword', $ret);
+
+                               return $ret;
+                       }
+
+                       // plain function, reduce args
+                       $value[2] = $this->reduce($value[2]);
+                       return $value;
+               case "unary":
+                       list(, $op, $exp) = $value;
+                       $exp = $this->reduce($exp);
+
+                       if ($exp[0] == "number") {
+                               switch ($op) {
+                               case "+":
+                                       return $exp;
+                               case "-":
+                                       $exp[1] *= -1;
+                                       return $exp;
+                               }
+                       }
+                       return array("string", "", array($op, $exp));
+               }
+
+               if ($forExpression) {
+                       switch ($value[0]) {
+                       case "keyword":
+                               if ($color = $this->coerceColor($value)) {
+                                       return $color;
+                               }
+                               break;
+                       case "raw_color":
+                               return $this->coerceColor($value);
+                       }
+               }
+
+               return $value;
+       }
+
+
+       // coerce a value for use in color operation
+       protected function coerceColor($value) {
+               switch($value[0]) {
+                       case 'color': return $value;
+                       case 'raw_color':
+                               $c = array("color", 0, 0, 0);
+                               $colorStr = substr($value[1], 1);
+                               $num = hexdec($colorStr);
+                               $width = strlen($colorStr) == 3 ? 16 : 256;
+
+                               for ($i = 3; $i > 0; $i--) { // 3 2 1
+                                       $t = $num % $width;
+                                       $num /= $width;
+
+                                       $c[$i] = $t * (256/$width) + $t * floor(16/$width);
+                               }
+
+                               return $c;
+                       case 'keyword':
+                               $name = $value[1];
+                               if (isset(self::$cssColors[$name])) {
+                                       $rgba = explode(',', self::$cssColors[$name]);
+
+                                       if(isset($rgba[3]))
+                                               return array('color', $rgba[0], $rgba[1], $rgba[2], $rgba[3]);
+
+                                       return array('color', $rgba[0], $rgba[1], $rgba[2]);
+                               }
+                               return null;
+               }
+       }
+
+       // make something string like into a string
+       protected function coerceString($value) {
+               switch ($value[0]) {
+               case "string":
+                       return $value;
+               case "keyword":
+                       return array("string", "", array($value[1]));
+               }
+               return null;
+       }
+
+       // turn list of length 1 into value type
+       protected function flattenList($value) {
+               if ($value[0] == "list" && count($value[2]) == 1) {
+                       return $this->flattenList($value[2][0]);
+               }
+               return $value;
+       }
+
+       protected function toBool($a) {
+               if ($a) return self::$TRUE;
+               else return self::$FALSE;
+       }
+
+       // evaluate an expression
+       protected function evaluate($exp) {
+               list(, $op, $left, $right, $whiteBefore, $whiteAfter) = $exp;
+
+               $left = $this->reduce($left, true);
+               $right = $this->reduce($right, true);
+
+               if ($leftColor = $this->coerceColor($left)) {
+                       $left = $leftColor;
+               }
+
+               if ($rightColor = $this->coerceColor($right)) {
+                       $right = $rightColor;
+               }
+
+               $ltype = $left[0];
+               $rtype = $right[0];
+
+               // operators that work on all types
+               if ($op == "and") {
+                       return $this->toBool($left == self::$TRUE && $right == self::$TRUE);
+               }
+
+               if ($op == "=") {
+                       return $this->toBool($this->eq($left, $right) );
+               }
+
+               if ($op == "+" && !is_null($str = $this->stringConcatenate($left, $right))) {
+                       return $str;
+               }
+
+               // type based operators
+               $fname = "op_${ltype}_${rtype}";
+               if (is_callable(array($this, $fname))) {
+                       $out = $this->$fname($op, $left, $right);
+                       if (!is_null($out)) return $out;
+               }
+
+               // make the expression look it did before being parsed
+               $paddedOp = $op;
+               if ($whiteBefore) $paddedOp = " " . $paddedOp;
+               if ($whiteAfter) $paddedOp .= " ";
+
+               return array("string", "", array($left, $paddedOp, $right));
+       }
+
+       protected function stringConcatenate($left, $right) {
+               if ($strLeft = $this->coerceString($left)) {
+                       if ($right[0] == "string") {
+                               $right[1] = "";
+                       }
+                       $strLeft[2][] = $right;
+                       return $strLeft;
+               }
+
+               if ($strRight = $this->coerceString($right)) {
+                       array_unshift($strRight[2], $left);
+                       return $strRight;
+               }
+       }
+
+
+       // make sure a color's components don't go out of bounds
+       protected function fixColor($c) {
+               foreach (range(1, 3) as $i) {
+                       if ($c[$i] < 0) $c[$i] = 0;
+                       if ($c[$i] > 255) $c[$i] = 255;
+               }
+
+               return $c;
+       }
+
+       protected function op_number_color($op, $lft, $rgt) {
+               if ($op == '+' || $op == '*') {
+                       return $this->op_color_number($op, $rgt, $lft);
+               }
+       }
+
+       protected function op_color_number($op, $lft, $rgt) {
+               if ($rgt[0] == '%') $rgt[1] /= 100;
+
+               return $this->op_color_color($op, $lft,
+                       array_fill(1, count($lft) - 1, $rgt[1]));
+       }
+
+       protected function op_color_color($op, $left, $right) {
+               $out = array('color');
+               $max = count($left) > count($right) ? count($left) : count($right);
+               foreach (range(1, $max - 1) as $i) {
+                       $lval = isset($left[$i]) ? $left[$i] : 0;
+                       $rval = isset($right[$i]) ? $right[$i] : 0;
+                       switch ($op) {
+                       case '+':
+                               $out[] = $lval + $rval;
+                               break;
+                       case '-':
+                               $out[] = $lval - $rval;
+                               break;
+                       case '*':
+                               $out[] = $lval * $rval;
+                               break;
+                       case '%':
+                               $out[] = $lval % $rval;
+                               break;
+                       case '/':
+                               if ($rval == 0) $this->throwError("evaluate error: can't divide by zero");
+                               $out[] = $lval / $rval;
+                               break;
+                       default:
+                               $this->throwError('evaluate error: color op number failed on op '.$op);
+                       }
+               }
+               return $this->fixColor($out);
+       }
+
+       function lib_red($color){
+               $color = $this->coerceColor($color);
+               if (is_null($color)) {
+                       $this->throwError('color expected for red()');
+               }
+
+               return $color[1];
+       }
+
+       function lib_green($color){
+               $color = $this->coerceColor($color);
+               if (is_null($color)) {
+                       $this->throwError('color expected for green()');
+               }
+
+               return $color[2];
+       }
+
+       function lib_blue($color){
+               $color = $this->coerceColor($color);
+               if (is_null($color)) {
+                       $this->throwError('color expected for blue()');
+               }
+
+               return $color[3];
+       }
+
+
+       // operator on two numbers
+       protected function op_number_number($op, $left, $right) {
+               $unit = empty($left[2]) ? $right[2] : $left[2];
+
+               $value = 0;
+               switch ($op) {
+               case '+':
+                       $value = $left[1] + $right[1];
+                       break;
+               case '*':
+                       $value = $left[1] * $right[1];
+                       break;
+               case '-':
+                       $value = $left[1] - $right[1];
+                       break;
+               case '%':
+                       $value = $left[1] % $right[1];
+                       break;
+               case '/':
+                       if ($right[1] == 0) $this->throwError('parse error: divide by zero');
+                       $value = $left[1] / $right[1];
+                       break;
+               case '<':
+                       return $this->toBool($left[1] < $right[1]);
+               case '>':
+                       return $this->toBool($left[1] > $right[1]);
+               case '>=':
+                       return $this->toBool($left[1] >= $right[1]);
+               case '=<':
+                       return $this->toBool($left[1] <= $right[1]);
+               default:
+                       $this->throwError('parse error: unknown number operator: '.$op);
+               }
+
+               return array("number", $value, $unit);
+       }
+
+
+       /* environment functions */
+
+       protected function makeOutputBlock($type, $selectors = null) {
+               $b = new stdclass;
+               $b->lines = array();
+               $b->children = array();
+               $b->selectors = $selectors;
+               $b->type = $type;
+               $b->parent = $this->scope;
+               return $b;
+       }
+
+       // the state of execution
+       protected function pushEnv($block = null) {
+               $e = new stdclass;
+               $e->parent = $this->env;
+               $e->store = array();
+               $e->block = $block;
+
+               $this->env = $e;
+               return $e;
+       }
+
+       // pop something off the stack
+       protected function popEnv() {
+               $old = $this->env;
+               $this->env = $this->env->parent;
+               return $old;
+       }
+
+       // set something in the current env
+       protected function set($name, $value) {
+               $this->env->store[$name] = $value;
+       }
+
+
+       // get the highest occurrence entry for a name
+       protected function get($name, $default=null) {
+               $current = $this->env;
+
+               $isArguments = $name == $this->vPrefix . 'arguments';
+               while ($current) {
+                       if ($isArguments && isset($current->arguments)) {
+                               return array('list', ' ', $current->arguments);
+                       }
+
+                       if (isset($current->store[$name]))
+                               return $current->store[$name];
+                       else {
+                               $current = isset($current->storeParent) ?
+                                       $current->storeParent : $current->parent;
+                       }
+               }
+
+               return $default;
+       }
+
+       // inject array of unparsed strings into environment as variables
+       protected function injectVariables($args) {
+               $this->pushEnv();
+               $parser = new lessc_parser($this, __METHOD__);
+               foreach ($args as $name => $strValue) {
+                       if ($name{0} != '@') $name = '@'.$name;
+                       $parser->count = 0;
+                       $parser->buffer = (string)$strValue;
+                       if (!$parser->propertyValue($value)) {
+                               throw new Exception("failed to parse passed in variable $name: $strValue");
+                       }
+
+                       $this->set($name, $value);
+               }
+       }
+
+       /**
+        * Initialize any static state, can initialize parser for a file
+        * $opts isn't used yet
+        */
+       public function __construct($fname = null) {
+               if ($fname !== null) {
+                       // used for deprecated parse method
+                       $this->_parseFile = $fname;
+               }
+       }
+
+       public function compile($string, $name = null) {
+               $locale = setlocale(LC_NUMERIC, 0);
+               setlocale(LC_NUMERIC, "C");
+
+               $this->parser = $this->makeParser($name);
+               $root = $this->parser->parse($string);
+
+               $this->env = null;
+               $this->scope = null;
+
+               $this->formatter = $this->newFormatter();
+
+               if (!empty($this->registeredVars)) {
+                       $this->injectVariables($this->registeredVars);
+               }
+
+               $this->sourceParser = $this->parser; // used for error messages
+               $this->compileBlock($root);
+
+               ob_start();
+               $this->formatter->block($this->scope);
+               $out = ob_get_clean();
+               setlocale(LC_NUMERIC, $locale);
+               return $out;
+       }
+
+       public function compileFile($fname, $outFname = null) {
+               if (!is_readable($fname)) {
+                       throw new Exception('load error: failed to find '.$fname);
+               }
+
+               $pi = pathinfo($fname);
+
+               $oldImport = $this->importDir;
+
+               $this->importDir = (array)$this->importDir;
+               $this->importDir[] = $pi['dirname'].'/';
+
+               $this->addParsedFile($fname);
+
+               $out = $this->compile(file_get_contents($fname), $fname);
+
+               $this->importDir = $oldImport;
+
+               if ($outFname !== null) {
+                       return file_put_contents($outFname, $out);
+               }
+
+               return $out;
+       }
+
+       // compile only if changed input has changed or output doesn't exist
+       public function checkedCompile($in, $out) {
+               if (!is_file($out) || filemtime($in) > filemtime($out)) {
+                       $this->compileFile($in, $out);
+                       return true;
+               }
+               return false;
+       }
+
+       /**
+        * Execute lessphp on a .less file or a lessphp cache structure
+        *
+        * The lessphp cache structure contains information about a specific
+        * less file having been parsed. It can be used as a hint for future
+        * calls to determine whether or not a rebuild is required.
+        *
+        * The cache structure contains two important keys that may be used
+        * externally:
+        *
+        * compiled: The final compiled CSS
+        * updated: The time (in seconds) the CSS was last compiled
+        *
+        * The cache structure is a plain-ol' PHP associative array and can
+        * be serialized and unserialized without a hitch.
+        *
+        * @param mixed $in Input
+        * @param bool $force Force rebuild?
+        * @return array lessphp cache structure
+        */
+       public function cachedCompile($in, $force = false) {
+               // assume no root
+               $root = null;
+
+               if (is_string($in)) {
+                       $root = $in;
+               } elseif (is_array($in) and isset($in['root'])) {
+                       if ($force or ! isset($in['files'])) {
+                               // If we are forcing a recompile or if for some reason the
+                               // structure does not contain any file information we should
+                               // specify the root to trigger a rebuild.
+                               $root = $in['root'];
+                       } elseif (isset($in['files']) and is_array($in['files'])) {
+                               foreach ($in['files'] as $fname => $ftime ) {
+                                       if (!file_exists($fname) or filemtime($fname) > $ftime) {
+                                               // One of the files we knew about previously has changed
+                                               // so we should look at our incoming root again.
+                                               $root = $in['root'];
+                                               break;
+                                       }
+                               }
+                       }
+               } else {
+                       // TODO: Throw an exception? We got neither a string nor something
+                       // that looks like a compatible lessphp cache structure.
+                       return null;
+               }
+
+               if ($root !== null) {
+                       // If we have a root value which means we should rebuild.
+                       $out = array();
+                       $out['root'] = $root;
+                       $out['compiled'] = $this->compileFile($root);
+                       $out['files'] = $this->allParsedFiles();
+                       $out['updated'] = time();
+                       return $out;
+               } else {
+                       // No changes, pass back the structure
+                       // we were given initially.
+                       return $in;
+               }
+
+       }
+
+       // parse and compile buffer
+       // This is deprecated
+       public function parse($str = null, $initialVariables = null) {
+               if (is_array($str)) {
+                       $initialVariables = $str;
+                       $str = null;
+               }
+
+               $oldVars = $this->registeredVars;
+               if ($initialVariables !== null) {
+                       $this->setVariables($initialVariables);
+               }
+
+               if ($str == null) {
+                       if (empty($this->_parseFile)) {
+                               throw new exception("nothing to parse");
+                       }
+
+                       $out = $this->compileFile($this->_parseFile);
+               } else {
+                       $out = $this->compile($str);
+               }
+
+               $this->registeredVars = $oldVars;
+               return $out;
+       }
+
+       protected function makeParser($name) {
+               $parser = new lessc_parser($this, $name);
+               $parser->writeComments = $this->preserveComments;
+
+               return $parser;
+       }
+
+       public function setFormatter($name) {
+               $this->formatterName = $name;
+       }
+
+       protected function newFormatter() {
+               $className = "lessc_formatter_lessjs";
+               if (!empty($this->formatterName)) {
+                       if (!is_string($this->formatterName))
+                               return $this->formatterName;
+                       $className = "lessc_formatter_$this->formatterName";
+               }
+
+               return new $className;
+       }
+
+       public function setPreserveComments($preserve) {
+               $this->preserveComments = $preserve;
+       }
+
+       public function registerFunction($name, $func) {
+               $this->libFunctions[$name] = $func;
+       }
+
+       public function unregisterFunction($name) {
+               unset($this->libFunctions[$name]);
+       }
+
+       public function setVariables($variables) {
+               $this->registeredVars = array_merge($this->registeredVars, $variables);
+       }
+
+       public function unsetVariable($name) {
+               unset($this->registeredVars[$name]);
+       }
+
+       public function setImportDir($dirs) {
+               $this->importDir = (array)$dirs;
+       }
+
+       public function addImportDir($dir) {
+               $this->importDir = (array)$this->importDir;
+               $this->importDir[] = $dir;
+       }
+
+       public function allParsedFiles() {
+               return $this->allParsedFiles;
+       }
+
+       protected function addParsedFile($file) {
+               $this->allParsedFiles[realpath($file)] = filemtime($file);
+       }
+
+       /**
+        * Uses the current value of $this->count to show line and line number
+        */
+       protected function throwError($msg = null) {
+               if ($this->sourceLoc >= 0) {
+                       $this->sourceParser->throwError($msg, $this->sourceLoc);
+               }
+               throw new exception($msg);
+       }
+
+       // compile file $in to file $out if $in is newer than $out
+       // returns true when it compiles, false otherwise
+       public static function ccompile($in, $out, $less = null) {
+               if ($less === null) {
+                       $less = new self;
+               }
+               return $less->checkedCompile($in, $out);
+       }
+
+       public static function cexecute($in, $force = false, $less = null) {
+               if ($less === null) {
+                       $less = new self;
+               }
+               return $less->cachedCompile($in, $force);
+       }
+
+       static protected $cssColors = array(
+               'aliceblue' => '240,248,255',
+               'antiquewhite' => '250,235,215',
+               'aqua' => '0,255,255',
+               'aquamarine' => '127,255,212',
+               'azure' => '240,255,255',
+               'beige' => '245,245,220',
+               'bisque' => '255,228,196',
+               'black' => '0,0,0',
+               'blanchedalmond' => '255,235,205',
+               'blue' => '0,0,255',
+               'blueviolet' => '138,43,226',
+               'brown' => '165,42,42',
+               'burlywood' => '222,184,135',
+               'cadetblue' => '95,158,160',
+               'chartreuse' => '127,255,0',
+               'chocolate' => '210,105,30',
+               'coral' => '255,127,80',
+               'cornflowerblue' => '100,149,237',
+               'cornsilk' => '255,248,220',
+               'crimson' => '220,20,60',
+               'cyan' => '0,255,255',
+               'darkblue' => '0,0,139',
+               'darkcyan' => '0,139,139',
+               'darkgoldenrod' => '184,134,11',
+               'darkgray' => '169,169,169',
+               'darkgreen' => '0,100,0',
+               'darkgrey' => '169,169,169',
+               'darkkhaki' => '189,183,107',
+               'darkmagenta' => '139,0,139',
+               'darkolivegreen' => '85,107,47',
+               'darkorange' => '255,140,0',
+               'darkorchid' => '153,50,204',
+               'darkred' => '139,0,0',
+               'darksalmon' => '233,150,122',
+               'darkseagreen' => '143,188,143',
+               'darkslateblue' => '72,61,139',
+               'darkslategray' => '47,79,79',
+               'darkslategrey' => '47,79,79',
+               'darkturquoise' => '0,206,209',
+               'darkviolet' => '148,0,211',
+               'deeppink' => '255,20,147',
+               'deepskyblue' => '0,191,255',
+               'dimgray' => '105,105,105',
+               'dimgrey' => '105,105,105',
+               'dodgerblue' => '30,144,255',
+               'firebrick' => '178,34,34',
+               'floralwhite' => '255,250,240',
+               'forestgreen' => '34,139,34',
+               'fuchsia' => '255,0,255',
+               'gainsboro' => '220,220,220',
+               'ghostwhite' => '248,248,255',
+               'gold' => '255,215,0',
+               'goldenrod' => '218,165,32',
+               'gray' => '128,128,128',
+               'green' => '0,128,0',
+               'greenyellow' => '173,255,47',
+               'grey' => '128,128,128',
+               'honeydew' => '240,255,240',
+               'hotpink' => '255,105,180',
+               'indianred' => '205,92,92',
+               'indigo' => '75,0,130',
+               'ivory' => '255,255,240',
+               'khaki' => '240,230,140',
+               'lavender' => '230,230,250',
+               'lavenderblush' => '255,240,245',
+               'lawngreen' => '124,252,0',
+               'lemonchiffon' => '255,250,205',
+               'lightblue' => '173,216,230',
+               'lightcoral' => '240,128,128',
+               'lightcyan' => '224,255,255',
+               'lightgoldenrodyellow' => '250,250,210',
+               'lightgray' => '211,211,211',
+               'lightgreen' => '144,238,144',
+               'lightgrey' => '211,211,211',
+               'lightpink' => '255,182,193',
+               'lightsalmon' => '255,160,122',
+               'lightseagreen' => '32,178,170',
+               'lightskyblue' => '135,206,250',
+               'lightslategray' => '119,136,153',
+               'lightslategrey' => '119,136,153',
+               'lightsteelblue' => '176,196,222',
+               'lightyellow' => '255,255,224',
+               'lime' => '0,255,0',
+               'limegreen' => '50,205,50',
+               'linen' => '250,240,230',
+               'magenta' => '255,0,255',
+               'maroon' => '128,0,0',
+               'mediumaquamarine' => '102,205,170',
+               'mediumblue' => '0,0,205',
+               'mediumorchid' => '186,85,211',
+               'mediumpurple' => '147,112,219',
+               'mediumseagreen' => '60,179,113',
+               'mediumslateblue' => '123,104,238',
+               'mediumspringgreen' => '0,250,154',
+               'mediumturquoise' => '72,209,204',
+               'mediumvioletred' => '199,21,133',
+               'midnightblue' => '25,25,112',
+               'mintcream' => '245,255,250',
+               'mistyrose' => '255,228,225',
+               'moccasin' => '255,228,181',
+               'navajowhite' => '255,222,173',
+               'navy' => '0,0,128',
+               'oldlace' => '253,245,230',
+               'olive' => '128,128,0',
+               'olivedrab' => '107,142,35',
+               'orange' => '255,165,0',
+               'orangered' => '255,69,0',
+               'orchid' => '218,112,214',
+               'palegoldenrod' => '238,232,170',
+               'palegreen' => '152,251,152',
+               'paleturquoise' => '175,238,238',
+               'palevioletred' => '219,112,147',
+               'papayawhip' => '255,239,213',
+               'peachpuff' => '255,218,185',
+               'peru' => '205,133,63',
+               'pink' => '255,192,203',
+               'plum' => '221,160,221',
+               'powderblue' => '176,224,230',
+               'purple' => '128,0,128',
+               'red' => '255,0,0',
+               'rosybrown' => '188,143,143',
+               'royalblue' => '65,105,225',
+               'saddlebrown' => '139,69,19',
+               'salmon' => '250,128,114',
+               'sandybrown' => '244,164,96',
+               'seagreen' => '46,139,87',
+               'seashell' => '255,245,238',
+               'sienna' => '160,82,45',
+               'silver' => '192,192,192',
+               'skyblue' => '135,206,235',
+               'slateblue' => '106,90,205',
+               'slategray' => '112,128,144',
+               'slategrey' => '112,128,144',
+               'snow' => '255,250,250',
+               'springgreen' => '0,255,127',
+               'steelblue' => '70,130,180',
+               'tan' => '210,180,140',
+               'teal' => '0,128,128',
+               'thistle' => '216,191,216',
+               'tomato' => '255,99,71',
+               'transparent' => '0,0,0,0',
+               'turquoise' => '64,224,208',
+               'violet' => '238,130,238',
+               'wheat' => '245,222,179',
+               'white' => '255,255,255',
+               'whitesmoke' => '245,245,245',
+               'yellow' => '255,255,0',
+               'yellowgreen' => '154,205,50'
+       );
+}
+
+// responsible for taking a string of LESS code and converting it into a
+// syntax tree
+class lessc_parser {
+       static protected $nextBlockId = 0; // used to uniquely identify blocks
+
+       static protected $precedence = array(
+               '=<' => 0,
+               '>=' => 0,
+               '=' => 0,
+               '<' => 0,
+               '>' => 0,
+
+               '+' => 1,
+               '-' => 1,
+               '*' => 2,
+               '/' => 2,
+               '%' => 2,
+       );
+
+       static protected $whitePattern;
+       static protected $commentMulti;
+
+       static protected $commentSingle = "//";
+       static protected $commentMultiLeft = "/*";
+       static protected $commentMultiRight = "*/";
+
+       // regex string to match any of the operators
+       static protected $operatorString;
+
+       // these properties will supress division unless it's inside parenthases
+       static protected $supressDivisionProps =
+               array('/border-radius$/i', '/^font$/i');
+
+       protected $blockDirectives = array("font-face", "keyframes", "page", "-moz-document", "viewport", "-moz-viewport", "-o-viewport", "-ms-viewport");
+       protected $lineDirectives = array("charset");
+
+       /**
+        * if we are in parens we can be more liberal with whitespace around
+        * operators because it must evaluate to a single value and thus is less
+        * ambiguous.
+        *
+        * Consider:
+        *     property1: 10 -5; // is two numbers, 10 and -5
+        *     property2: (10 -5); // should evaluate to 5
+        */
+       protected $inParens = false;
+
+       // caches preg escaped literals
+       static protected $literalCache = array();
+
+       public function __construct($lessc, $sourceName = null) {
+               $this->eatWhiteDefault = true;
+               // reference to less needed for vPrefix, mPrefix, and parentSelector
+               $this->lessc = $lessc;
+
+               $this->sourceName = $sourceName; // name used for error messages
+
+               $this->writeComments = false;
+
+               if (!self::$operatorString) {
+                       self::$operatorString =
+                               '('.implode('|', array_map(array('lessc', 'preg_quote'),
+                                       array_keys(self::$precedence))).')';
+
+                       $commentSingle = lessc::preg_quote(self::$commentSingle);
+                       $commentMultiLeft = lessc::preg_quote(self::$commentMultiLeft);
+                       $commentMultiRight = lessc::preg_quote(self::$commentMultiRight);
+
+                       self::$commentMulti = $commentMultiLeft.'.*?'.$commentMultiRight;
+                       self::$whitePattern = '/'.$commentSingle.'[^\n]*\s*|('.self::$commentMulti.')\s*|\s+/Ais';
+               }
+       }
+
+       public function parse($buffer) {
+               $this->count = 0;
+               $this->line = 1;
+
+               $this->env = null; // block stack
+               $this->buffer = $this->writeComments ? $buffer : $this->removeComments($buffer);
+               $this->pushSpecialBlock("root");
+               $this->eatWhiteDefault = true;
+               $this->seenComments = array();
+
+               // trim whitespace on head
+               // if (preg_match('/^\s+/', $this->buffer, $m)) {
+               //      $this->line += substr_count($m[0], "\n");
+               //      $this->buffer = ltrim($this->buffer);
+               // }
+               $this->whitespace();
+
+               // parse the entire file
+               $lastCount = $this->count;
+               while (false !== $this->parseChunk());
+
+               if ($this->count != strlen($this->buffer))
+                       $this->throwError();
+
+               // TODO report where the block was opened
+               if (!is_null($this->env->parent))
+                       throw new exception('parse error: unclosed block');
+
+               return $this->env;
+       }
+
+       /**
+        * Parse a single chunk off the head of the buffer and append it to the
+        * current parse environment.
+        * Returns false when the buffer is empty, or when there is an error.
+        *
+        * This function is called repeatedly until the entire document is
+        * parsed.
+        *
+        * This parser is most similar to a recursive descent parser. Single
+        * functions represent discrete grammatical rules for the language, and
+        * they are able to capture the text that represents those rules.
+        *
+        * Consider the function lessc::keyword(). (all parse functions are
+        * structured the same)
+        *
+        * The function takes a single reference argument. When calling the
+        * function it will attempt to match a keyword on the head of the buffer.
+        * If it is successful, it will place the keyword in the referenced
+        * argument, advance the position in the buffer, and return true. If it
+        * fails then it won't advance the buffer and it will return false.
+        *
+        * All of these parse functions are powered by lessc::match(), which behaves
+        * the same way, but takes a literal regular expression. Sometimes it is
+        * more convenient to use match instead of creating a new function.
+        *
+        * Because of the format of the functions, to parse an entire string of
+        * grammatical rules, you can chain them together using &&.
+        *
+        * But, if some of the rules in the chain succeed before one fails, then
+        * the buffer position will be left at an invalid state. In order to
+        * avoid this, lessc::seek() is used to remember and set buffer positions.
+        *
+        * Before parsing a chain, use $s = $this->seek() to remember the current
+        * position into $s. Then if a chain fails, use $this->seek($s) to
+        * go back where we started.
+        */
+       protected function parseChunk() {
+               if (empty($this->buffer)) return false;
+               $s = $this->seek();
+
+               // setting a property
+               if ($this->keyword($key) && $this->assign() &&
+                       $this->propertyValue($value, $key) && $this->end())
+               {
+                       $this->append(array('assign', $key, $value), $s);
+                       return true;
+               } else {
+                       $this->seek($s);
+               }
+
+
+               // look for special css blocks
+               if ($this->literal('@', false)) {
+                       $this->count--;
+
+                       // media
+                       if ($this->literal('@media')) {
+                               if (($this->mediaQueryList($mediaQueries) || true)
+                                       && $this->literal('{'))
+                               {
+                                       $media = $this->pushSpecialBlock("media");
+                                       $media->queries = is_null($mediaQueries) ? array() : $mediaQueries;
+                                       return true;
+                               } else {
+                                       $this->seek($s);
+                                       return false;
+                               }
+                       }
+
+                       if ($this->literal("@", false) && $this->keyword($dirName)) {
+                               if ($this->isDirective($dirName, $this->blockDirectives)) {
+                                       if (($this->openString("{", $dirValue, null, array(";")) || true) &&
+                                               $this->literal("{"))
+                                       {
+                                               $dir = $this->pushSpecialBlock("directive");
+                                               $dir->name = $dirName;
+                                               if (isset($dirValue)) $dir->value = $dirValue;
+                                               return true;
+                                       }
+                               } elseif ($this->isDirective($dirName, $this->lineDirectives)) {
+                                       if ($this->propertyValue($dirValue) && $this->end()) {
+                                               $this->append(array("directive", $dirName, $dirValue));
+                                               return true;
+                                       }
+                               }
+                       }
+
+                       $this->seek($s);
+               }
+
+               // setting a variable
+               if ($this->variable($var) && $this->assign() &&
+                       $this->propertyValue($value) && $this->end())
+               {
+                       $this->append(array('assign', $var, $value), $s);
+                       return true;
+               } else {
+                       $this->seek($s);
+               }
+
+               if ($this->import($importValue)) {
+                       $this->append($importValue, $s);
+                       return true;
+               }
+
+               // opening parametric mixin
+               if ($this->tag($tag, true) && $this->argumentDef($args, $isVararg) &&
+                       ($this->guards($guards) || true) &&
+                       $this->literal('{'))
+               {
+                       $block = $this->pushBlock($this->fixTags(array($tag)));
+                       $block->args = $args;
+                       $block->isVararg = $isVararg;
+                       if (!empty($guards)) $block->guards = $guards;
+                       return true;
+               } else {
+                       $this->seek($s);
+               }
+
+               // opening a simple block
+               if ($this->tags($tags) && $this->literal('{')) {
+                       $tags = $this->fixTags($tags);
+                       $this->pushBlock($tags);
+                       return true;
+               } else {
+                       $this->seek($s);
+               }
+
+               // closing a block
+               if ($this->literal('}', false)) {
+                       try {
+                               $block = $this->pop();
+                       } catch (exception $e) {
+                               $this->seek($s);
+                               $this->throwError($e->getMessage());
+                       }
+
+                       $hidden = false;
+                       if (is_null($block->type)) {
+                               $hidden = true;
+                               if (!isset($block->args)) {
+                                       foreach ($block->tags as $tag) {
+                                               if (!is_string($tag) || $tag{0} != $this->lessc->mPrefix) {
+                                                       $hidden = false;
+                                                       break;
+                                               }
+                                       }
+                               }
+
+                               foreach ($block->tags as $tag) {
+                                       if (is_string($tag)) {
+                                               $this->env->children[$tag][] = $block;
+                                       }
+                               }
+                       }
+
+                       if (!$hidden) {
+                               $this->append(array('block', $block), $s);
+                       }
+
+                       // this is done here so comments aren't bundled into he block that
+                       // was just closed
+                       $this->whitespace();
+                       return true;
+               }
+
+               // mixin
+               if ($this->mixinTags($tags) &&
+                       ($this->argumentDef($argv, $isVararg) || true) &&
+                       ($this->keyword($suffix) || true) && $this->end())
+               {
+                       $tags = $this->fixTags($tags);
+                       $this->append(array('mixin', $tags, $argv, $suffix), $s);
+                       return true;
+               } else {
+                       $this->seek($s);
+               }
+
+               // spare ;
+               if ($this->literal(';')) return true;
+
+               return false; // got nothing, throw error
+       }
+
+       protected function isDirective($dirname, $directives) {
+               // TODO: cache pattern in parser
+               $pattern = implode("|",
+                       array_map(array("lessc", "preg_quote"), $directives));
+               $pattern = '/^(-[a-z-]+-)?(' . $pattern . ')$/i';
+
+               return preg_match($pattern, $dirname);
+       }
+
+       protected function fixTags($tags) {
+               // move @ tags out of variable namespace
+               foreach ($tags as &$tag) {
+                       if ($tag{0} == $this->lessc->vPrefix)
+                               $tag[0] = $this->lessc->mPrefix;
+               }
+               return $tags;
+       }
+
+       // a list of expressions
+       protected function expressionList(&$exps) {
+               $values = array();
+
+               while ($this->expression($exp)) {
+                       $values[] = $exp;
+               }
+
+               if (count($values) == 0) return false;
+
+               $exps = lessc::compressList($values, ' ');
+               return true;
+       }
+
+       /**
+        * Attempt to consume an expression.
+        * @link http://en.wikipedia.org/wiki/Operator-precedence_parser#Pseudo-code
+        */
+       protected function expression(&$out) {
+               if ($this->value($lhs)) {
+                       $out = $this->expHelper($lhs, 0);
+
+                       // look for / shorthand
+                       if (!empty($this->env->supressedDivision)) {
+                               unset($this->env->supressedDivision);
+                               $s = $this->seek();
+                               if ($this->literal("/") && $this->value($rhs)) {
+                                       $out = array("list", "",
+                                               array($out, array("keyword", "/"), $rhs));
+                               } else {
+                                       $this->seek($s);
+                               }
+                       }
+
+                       return true;
+               }
+               return false;
+       }
+
+       /**
+        * recursively parse infix equation with $lhs at precedence $minP
+        */
+       protected function expHelper($lhs, $minP) {
+               $this->inExp = true;
+               $ss = $this->seek();
+
+               while (true) {
+                       $whiteBefore = isset($this->buffer[$this->count - 1]) &&
+                               ctype_space($this->buffer[$this->count - 1]);
+
+                       // If there is whitespace before the operator, then we require
+                       // whitespace after the operator for it to be an expression
+                       $needWhite = $whiteBefore && !$this->inParens;
+
+                       if ($this->match(self::$operatorString.($needWhite ? '\s' : ''), $m) && self::$precedence[$m[1]] >= $minP) {
+                               if (!$this->inParens && isset($this->env->currentProperty) && $m[1] == "/" && empty($this->env->supressedDivision)) {
+                                       foreach (self::$supressDivisionProps as $pattern) {
+                                               if (preg_match($pattern, $this->env->currentProperty)) {
+                                                       $this->env->supressedDivision = true;
+                                                       break 2;
+                                               }
+                                       }
+                               }
+
+
+                               $whiteAfter = isset($this->buffer[$this->count - 1]) &&
+                                       ctype_space($this->buffer[$this->count - 1]);
+
+                               if (!$this->value($rhs)) break;
+
+                               // peek for next operator to see what to do with rhs
+                               if ($this->peek(self::$operatorString, $next) && self::$precedence[$next[1]] > self::$precedence[$m[1]]) {
+                                       $rhs = $this->expHelper($rhs, self::$precedence[$next[1]]);
+                               }
+
+                               $lhs = array('expression', $m[1], $lhs, $rhs, $whiteBefore, $whiteAfter);
+                               $ss = $this->seek();
+
+                               continue;
+                       }
+
+                       break;
+               }
+
+               $this->seek($ss);
+
+               return $lhs;
+       }
+
+       // consume a list of values for a property
+       public function propertyValue(&$value, $keyName = null) {
+               $values = array();
+
+               if ($keyName !== null) $this->env->currentProperty = $keyName;
+
+               $s = null;
+               while ($this->expressionList($v)) {
+                       $values[] = $v;
+                       $s = $this->seek();
+                       if (!$this->literal(',')) break;
+               }
+
+               if ($s) $this->seek($s);
+
+               if ($keyName !== null) unset($this->env->currentProperty);
+
+               if (count($values) == 0) return false;
+
+               $value = lessc::compressList($values, ', ');
+               return true;
+       }
+
+       protected function parenValue(&$out) {
+               $s = $this->seek();
+
+               // speed shortcut
+               if (isset($this->buffer[$this->count]) && $this->buffer[$this->count] != "(") {
+                       return false;
+               }
+
+               $inParens = $this->inParens;
+               if ($this->literal("(") &&
+                       ($this->inParens = true) && $this->expression($exp) &&
+                       $this->literal(")"))
+               {
+                       $out = $exp;
+                       $this->inParens = $inParens;
+                       return true;
+               } else {
+                       $this->inParens = $inParens;
+                       $this->seek($s);
+               }
+
+               return false;
+       }
+
+       // a single value
+       protected function value(&$value) {
+               $s = $this->seek();
+
+               // speed shortcut
+               if (isset($this->buffer[$this->count]) && $this->buffer[$this->count] == "-") {
+                       // negation
+                       if ($this->literal("-", false) &&
+                               (($this->variable($inner) && $inner = array("variable", $inner)) ||
+                               $this->unit($inner) ||
+                               $this->parenValue($inner)))
+                       {
+                               $value = array("unary", "-", $inner);
+                               return true;
+                       } else {
+                               $this->seek($s);
+                       }
+               }
+
+               if ($this->parenValue($value)) return true;
+               if ($this->unit($value)) return true;
+               if ($this->color($value)) return true;
+               if ($this->func($value)) return true;
+               if ($this->string($value)) return true;
+
+               if ($this->keyword($word)) {
+                       $value = array('keyword', $word);
+                       return true;
+               }
+
+               // try a variable
+               if ($this->variable($var)) {
+                       $value = array('variable', $var);
+                       return true;
+               }
+
+               // unquote string (should this work on any type?
+               if ($this->literal("~") && $this->string($str)) {
+                       $value = array("escape", $str);
+                       return true;
+               } else {
+                       $this->seek($s);
+               }
+
+               // css hack: \0
+               if ($this->literal('\\') && $this->match('([0-9]+)', $m)) {
+                       $value = array('keyword', '\\'.$m[1]);
+                       return true;
+               } else {
+                       $this->seek($s);
+               }
+
+               return false;
+       }
+
+       // an import statement
+       protected function import(&$out) {
+               $s = $this->seek();
+               if (!$this->literal('@import')) return false;
+
+               // @import "something.css" media;
+               // @import url("something.css") media;
+               // @import url(something.css) media;
+
+               if ($this->propertyValue($value)) {
+                       $out = array("import", $value);
+                       return true;
+               }
+       }
+
+       protected function mediaQueryList(&$out) {
+               if ($this->genericList($list, "mediaQuery", ",", false)) {
+                       $out = $list[2];
+                       return true;
+               }
+               return false;
+       }
+
+       protected function mediaQuery(&$out) {
+               $s = $this->seek();
+
+               $expressions = null;
+               $parts = array();
+
+               if (($this->literal("only") && ($only = true) || $this->literal("not") && ($not = true) || true) && $this->keyword($mediaType)) {
+                       $prop = array("mediaType");
+                       if (isset($only)) $prop[] = "only";
+                       if (isset($not)) $prop[] = "not";
+                       $prop[] = $mediaType;
+                       $parts[] = $prop;
+               } else {
+                       $this->seek($s);
+               }
+
+
+               if (!empty($mediaType) && !$this->literal("and")) {
+                       // ~
+               } else {
+                       $this->genericList($expressions, "mediaExpression", "and", false);
+                       if (is_array($expressions)) $parts = array_merge($parts, $expressions[2]);
+               }
+
+               if (count($parts) == 0) {
+                       $this->seek($s);
+                       return false;
+               }
+
+               $out = $parts;
+               return true;
+       }
+
+       protected function mediaExpression(&$out) {
+               $s = $this->seek();
+               $value = null;
+               if ($this->literal("(") &&
+                       $this->keyword($feature) &&
+                       ($this->literal(":") && $this->expression($value) || true) &&
+                       $this->literal(")"))
+               {
+                       $out = array("mediaExp", $feature);
+                       if ($value) $out[] = $value;
+                       return true;
+               } elseif ($this->variable($variable)) {
+                       $out = array('variable', $variable);
+                       return true;
+               }
+
+               $this->seek($s);
+               return false;
+       }
+
+       // an unbounded string stopped by $end
+       protected function openString($end, &$out, $nestingOpen=null, $rejectStrs = null) {
+               $oldWhite = $this->eatWhiteDefault;
+               $this->eatWhiteDefault = false;
+
+               $stop = array("'", '"', "@{", $end);
+               $stop = array_map(array("lessc", "preg_quote"), $stop);
+               // $stop[] = self::$commentMulti;
+
+               if (!is_null($rejectStrs)) {
+                       $stop = array_merge($stop, $rejectStrs);
+               }
+
+               $patt = '(.*?)('.implode("|", $stop).')';
+
+               $nestingLevel = 0;
+
+               $content = array();
+               while ($this->match($patt, $m, false)) {
+                       if (!empty($m[1])) {
+                               $content[] = $m[1];
+                               if ($nestingOpen) {
+                                       $nestingLevel += substr_count($m[1], $nestingOpen);
+                               }
+                       }
+
+                       $tok = $m[2];
+
+                       $this->count-= strlen($tok);
+                       if ($tok == $end) {
+                               if ($nestingLevel == 0) {
+                                       break;
+                               } else {
+                                       $nestingLevel--;
+                               }
+                       }
+
+                       if (($tok == "'" || $tok == '"') && $this->string($str)) {
+                               $content[] = $str;
+                               continue;
+                       }
+
+                       if ($tok == "@{" && $this->interpolation($inter)) {
+                               $content[] = $inter;
+                               continue;
+                       }
+
+                       if (!empty($rejectStrs) && in_array($tok, $rejectStrs)) {
+                               break;
+                       }
+
+                       $content[] = $tok;
+                       $this->count+= strlen($tok);
+               }
+
+               $this->eatWhiteDefault = $oldWhite;
+
+               if (count($content) == 0) return false;
+
+               // trim the end
+               if (is_string(end($content))) {
+                       $content[count($content) - 1] = rtrim(end($content));
+               }
+
+               $out = array("string", "", $content);
+               return true;
+       }
+
+       protected function string(&$out) {
+               $s = $this->seek();
+               if ($this->literal('"', false)) {
+                       $delim = '"';
+               } elseif ($this->literal("'", false)) {
+                       $delim = "'";
+               } else {
+                       return false;
+               }
+
+               $content = array();
+
+               // look for either ending delim , escape, or string interpolation
+               $patt = '([^\n]*?)(@\{|\\\\|' .
+                       lessc::preg_quote($delim).')';
+
+               $oldWhite = $this->eatWhiteDefault;
+               $this->eatWhiteDefault = false;
+
+               while ($this->match($patt, $m, false)) {
+                       $content[] = $m[1];
+                       if ($m[2] == "@{") {
+                               $this->count -= strlen($m[2]);
+                               if ($this->interpolation($inter, false)) {
+                                       $content[] = $inter;
+                               } else {
+                                       $this->count += strlen($m[2]);
+                                       $content[] = "@{"; // ignore it
+                               }
+                       } elseif ($m[2] == '\\') {
+                               $content[] = $m[2];
+                               if ($this->literal($delim, false)) {
+                                       $content[] = $delim;
+                               }
+                       } else {
+                               $this->count -= strlen($delim);
+                               break; // delim
+                       }
+               }
+
+               $this->eatWhiteDefault = $oldWhite;
+
+               if ($this->literal($delim)) {
+                       $out = array("string", $delim, $content);
+                       return true;
+               }
+
+               $this->seek($s);
+               return false;
+       }
+
+       protected function interpolation(&$out) {
+               $oldWhite = $this->eatWhiteDefault;
+               $this->eatWhiteDefault = true;
+
+               $s = $this->seek();
+               if ($this->literal("@{") &&
+                       $this->openString("}", $interp, null, array("'", '"', ";")) &&
+                       $this->literal("}", false))
+               {
+                       $out = array("interpolate", $interp);
+                       $this->eatWhiteDefault = $oldWhite;
+                       if ($this->eatWhiteDefault) $this->whitespace();
+                       return true;
+               }
+
+               $this->eatWhiteDefault = $oldWhite;
+               $this->seek($s);
+               return false;
+       }
+
+       protected function unit(&$unit) {
+               // speed shortcut
+               if (isset($this->buffer[$this->count])) {
+                       $char = $this->buffer[$this->count];
+                       if (!ctype_digit($char) && $char != ".") return false;
+               }
+
+               if ($this->match('([0-9]+(?:\.[0-9]*)?|\.[0-9]+)([%a-zA-Z]+)?', $m)) {
+                       $unit = array("number", $m[1], empty($m[2]) ? "" : $m[2]);
+                       return true;
+               }
+               return false;
+       }
+
+       // a # color
+       protected function color(&$out) {
+               if ($this->match('(#(?:[0-9a-f]{8}|[0-9a-f]{6}|[0-9a-f]{3}))', $m)) {
+                       if (strlen($m[1]) > 7) {
+                               $out = array("string", "", array($m[1]));
+                       } else {
+                               $out = array("raw_color", $m[1]);
+                       }
+                       return true;
+               }
+
+               return false;
+       }
+
+       // consume an argument definition list surrounded by ()
+       // each argument is a variable name with optional value
+       // or at the end a ... or a variable named followed by ...
+       // arguments are separated by , unless a ; is in the list, then ; is the
+       // delimiter.
+       protected function argumentDef(&$args, &$isVararg) {
+               $s = $this->seek();
+               if (!$this->literal('(')) return false;
+
+               $values = array();
+               $delim = ",";
+               $method = "expressionList";
+
+               $isVararg = false;
+               while (true) {
+                       if ($this->literal("...")) {
+                               $isVararg = true;
+                               break;
+                       }
+
+                       if ($this->$method($value)) {
+                               if ($value[0] == "variable") {
+                                       $arg = array("arg", $value[1]);
+                                       $ss = $this->seek();
+
+                                       if ($this->assign() && $this->$method($rhs)) {
+                                               $arg[] = $rhs;
+                                       } else {
+                                               $this->seek($ss);
+                                               if ($this->literal("...")) {
+                                                       $arg[0] = "rest";
+                                                       $isVararg = true;
+                                               }
+                                       }
+
+                                       $values[] = $arg;
+                                       if ($isVararg) break;
+                                       continue;
+                               } else {
+                                       $values[] = array("lit", $value);
+                               }
+                       }
+
+
+                       if (!$this->literal($delim)) {
+                               if ($delim == "," && $this->literal(";")) {
+                                       // found new delim, convert existing args
+                                       $delim = ";";
+                                       $method = "propertyValue";
+
+                                       // transform arg list
+                                       if (isset($values[1])) { // 2 items
+                                               $newList = array();
+                                               foreach ($values as $i => $arg) {
+                                                       switch($arg[0]) {
+                                                       case "arg":
+                                                               if ($i) {
+                                                                       $this->throwError("Cannot mix ; and , as delimiter types");
+                                                               }
+                                                               $newList[] = $arg[2];
+                                                               break;
+                                                       case "lit":
+                                                               $newList[] = $arg[1];
+                                                               break;
+                                                       case "rest":
+                                                               $this->throwError("Unexpected rest before semicolon");
+                                                       }
+                                               }
+
+                                               $newList = array("list", ", ", $newList);
+
+                                               switch ($values[0][0]) {
+                                               case "arg":
+                                                       $newArg = array("arg", $values[0][1], $newList);
+                                                       break;
+                                               case "lit":
+                                                       $newArg = array("lit", $newList);
+                                                       break;
+                                               }
+
+                                       } elseif ($values) { // 1 item
+                                               $newArg = $values[0];
+                                       }
+
+                                       if ($newArg) {
+                                               $values = array($newArg);
+                                       }
+                               } else {
+                                       break;
+                               }
+                       }
+               }
+
+               if (!$this->literal(')')) {
+                       $this->seek($s);
+                       return false;
+               }
+
+               $args = $values;
+
+               return true;
+       }
+
+       // consume a list of tags
+       // this accepts a hanging delimiter
+       protected function tags(&$tags, $simple = false, $delim = ',') {
+               $tags = array();
+               while ($this->tag($tt, $simple)) {
+                       $tags[] = $tt;
+                       if (!$this->literal($delim)) break;
+               }
+               if (count($tags) == 0) return false;
+
+               return true;
+       }
+
+       // list of tags of specifying mixin path
+       // optionally separated by > (lazy, accepts extra >)
+       protected function mixinTags(&$tags) {
+               $s = $this->seek();
+               $tags = array();
+               while ($this->tag($tt, true)) {
+                       $tags[] = $tt;
+                       $this->literal(">");
+               }
+
+               if (count($tags) == 0) return false;
+
+               return true;
+       }
+
+       // a bracketed value (contained within in a tag definition)
+       protected function tagBracket(&$parts, &$hasExpression) {
+               // speed shortcut
+               if (isset($this->buffer[$this->count]) && $this->buffer[$this->count] != "[") {
+                       return false;
+               }
+
+               $s = $this->seek();
+
+               $hasInterpolation = false;
+
+               if ($this->literal("[", false)) {
+                       $attrParts = array("[");
+                       // keyword, string, operator
+                       while (true) {
+                               if ($this->literal("]", false)) {
+                                       $this->count--;
+                                       break; // get out early
+                               }
+
+                               if ($this->match('\s+', $m)) {
+                                       $attrParts[] = " ";
+                                       continue;
+                               }
+                               if ($this->string($str)) {
+                                       // escape parent selector, (yuck)
+                                       foreach ($str[2] as &$chunk) {
+                                               $chunk = str_replace($this->lessc->parentSelector, "$&$", $chunk);
+                                       }
+
+                                       $attrParts[] = $str;
+                                       $hasInterpolation = true;
+                                       continue;
+                               }
+
+                               if ($this->keyword($word)) {
+                                       $attrParts[] = $word;
+                                       continue;
+                               }
+
+                               if ($this->interpolation($inter, false)) {
+                                       $attrParts[] = $inter;
+                                       $hasInterpolation = true;
+                                       continue;
+                               }
+
+                               // operator, handles attr namespace too
+                               if ($this->match('[|-~\$\*\^=]+', $m)) {
+                                       $attrParts[] = $m[0];
+                                       continue;
+                               }
+
+                               break;
+                       }
+
+                       if ($this->literal("]", false)) {
+                               $attrParts[] = "]";
+                               foreach ($attrParts as $part) {
+                                       $parts[] = $part;
+                               }
+                               $hasExpression = $hasExpression || $hasInterpolation;
+                               return true;
+                       }
+                       $this->seek($s);
+               }
+
+               $this->seek($s);
+               return false;
+       }
+
+       // a space separated list of selectors
+       protected function tag(&$tag, $simple = false) {
+               if ($simple)
+                       $chars = '^@,:;{}\][>\(\) "\'';
+               else
+                       $chars = '^@,;{}["\'';
+
+               $s = $this->seek();
+
+               $hasExpression = false;
+               $parts = array();
+               while ($this->tagBracket($parts, $hasExpression));
+
+               $oldWhite = $this->eatWhiteDefault;
+               $this->eatWhiteDefault = false;
+
+               while (true) {
+                       if ($this->match('(['.$chars.'0-9]['.$chars.']*)', $m)) {
+                               $parts[] = $m[1];
+                               if ($simple) break;
+
+                               while ($this->tagBracket($parts, $hasExpression));
+                               continue;
+                       }
+
+                       if (isset($this->buffer[$this->count]) && $this->buffer[$this->count] == "@") {
+                               if ($this->interpolation($interp)) {
+                                       $hasExpression = true;
+                                       $interp[2] = true; // don't unescape
+                                       $parts[] = $interp;
+                                       continue;
+                               }
+
+                               if ($this->literal("@")) {
+                                       $parts[] = "@";
+                                       continue;
+                               }
+                       }
+
+                       if ($this->unit($unit)) { // for keyframes
+                               $parts[] = $unit[1];
+                               $parts[] = $unit[2];
+                               continue;
+                       }
+
+                       break;
+               }
+
+               $this->eatWhiteDefault = $oldWhite;
+               if (!$parts) {
+                       $this->seek($s);
+                       return false;
+               }
+
+               if ($hasExpression) {
+                       $tag = array("exp", array("string", "", $parts));
+               } else {
+                       $tag = trim(implode($parts));
+               }
+
+               $this->whitespace();
+               return true;
+       }
+
+       // a css function
+       protected function func(&$func) {
+               $s = $this->seek();
+
+               if ($this->match('(%|[\w\-_][\w\-_:\.]+|[\w_])', $m) && $this->literal('(')) {
+                       $fname = $m[1];
+
+                       $sPreArgs = $this->seek();
+
+                       $args = array();
+                       while (true) {
+                               $ss = $this->seek();
+                               // this ugly nonsense is for ie filter properties
+                               if ($this->keyword($name) && $this->literal('=') && $this->expressionList($value)) {
+                                       $args[] = array("string", "", array($name, "=", $value));
+                               } else {
+                                       $this->seek($ss);
+                                       if ($this->expressionList($value)) {
+                                               $args[] = $value;
+                                       }
+                               }
+
+                               if (!$this->literal(',')) break;
+                       }
+                       $args = array('list', ',', $args);
+
+                       if ($this->literal(')')) {
+                               $func = array('function', $fname, $args);
+                               return true;
+                       } elseif ($fname == 'url') {
+                               // couldn't parse and in url? treat as string
+                               $this->seek($sPreArgs);
+                               if ($this->openString(")", $string) && $this->literal(")")) {
+                                       $func = array('function', $fname, $string);
+                                       return true;
+                               }
+                       }
+               }
+
+               $this->seek($s);
+               return false;
+       }
+
+       // consume a less variable
+       protected function variable(&$name) {
+               $s = $this->seek();
+               if ($this->literal($this->lessc->vPrefix, false) &&
+                       ($this->variable($sub) || $this->keyword($name)))
+               {
+                       if (!empty($sub)) {
+                               $name = array('variable', $sub);
+                       } else {
+                               $name = $this->lessc->vPrefix.$name;
+                       }
+                       return true;
+               }
+
+               $name = null;
+               $this->seek($s);
+               return false;
+       }
+
+       /**
+        * Consume an assignment operator
+        * Can optionally take a name that will be set to the current property name
+        */
+       protected function assign($name = null) {
+               if ($name) $this->currentProperty = $name;
+               return $this->literal(':') || $this->literal('=');
+       }
+
+       // consume a keyword
+       protected function keyword(&$word) {
+               if ($this->match('([\w_\-\*!"][\w\-_"]*)', $m)) {
+                       $word = $m[1];
+                       return true;
+               }
+               return false;
+       }
+
+       // consume an end of statement delimiter
+       protected function end() {
+               if ($this->literal(';')) {
+                       return true;
+               } elseif ($this->count == strlen($this->buffer) || $this->buffer[$this->count] == '}') {
+                       // if there is end of file or a closing block next then we don't need a ;
+                       return true;
+               }
+               return false;
+       }
+
+       protected function guards(&$guards) {
+               $s = $this->seek();
+
+               if (!$this->literal("when")) {
+                       $this->seek($s);
+                       return false;
+               }
+
+               $guards = array();
+
+               while ($this->guardGroup($g)) {
+                       $guards[] = $g;
+                       if (!$this->literal(",")) break;
+               }
+
+               if (count($guards) == 0) {
+                       $guards = null;
+                       $this->seek($s);
+                       return false;
+               }
+
+               return true;
+       }
+
+       // a bunch of guards that are and'd together
+       // TODO rename to guardGroup
+       protected function guardGroup(&$guardGroup) {
+               $s = $this->seek();
+               $guardGroup = array();
+               while ($this->guard($guard)) {
+                       $guardGroup[] = $guard;
+                       if (!$this->literal("and")) break;
+               }
+
+               if (count($guardGroup) == 0) {
+                       $guardGroup = null;
+                       $this->seek($s);
+                       return false;
+               }
+
+               return true;
+       }
+
+       protected function guard(&$guard) {
+               $s = $this->seek();
+               $negate = $this->literal("not");
+
+               if ($this->literal("(") && $this->expression($exp) && $this->literal(")")) {
+                       $guard = $exp;
+                       if ($negate) $guard = array("negate", $guard);
+                       return true;
+               }
+
+               $this->seek($s);
+               return false;
+       }
+
+       /* raw parsing functions */
+
+       protected function literal($what, $eatWhitespace = null) {
+               if ($eatWhitespace === null) $eatWhitespace = $this->eatWhiteDefault;
+
+               // shortcut on single letter
+               if (!isset($what[1]) && isset($this->buffer[$this->count])) {
+                       if ($this->buffer[$this->count] == $what) {
+                               if (!$eatWhitespace) {
+                                       $this->count++;
+                                       return true;
+                               }
+                               // goes below...
+                       } else {
+                               return false;
+                       }
+               }
+
+               if (!isset(self::$literalCache[$what])) {
+                       self::$literalCache[$what] = lessc::preg_quote($what);
+               }
+
+               return $this->match(self::$literalCache[$what], $m, $eatWhitespace);
+       }
+
+       protected function genericList(&$out, $parseItem, $delim="", $flatten=true) {
+               $s = $this->seek();
+               $items = array();
+               while ($this->$parseItem($value)) {
+                       $items[] = $value;
+                       if ($delim) {
+                               if (!$this->literal($delim)) break;
+                       }
+               }
+
+               if (count($items) == 0) {
+                       $this->seek($s);
+                       return false;
+               }
+
+               if ($flatten && count($items) == 1) {
+                       $out = $items[0];
+               } else {
+                       $out = array("list", $delim, $items);
+               }
+
+               return true;
+       }
+
+
+       // advance counter to next occurrence of $what
+       // $until - don't include $what in advance
+       // $allowNewline, if string, will be used as valid char set
+       protected function to($what, &$out, $until = false, $allowNewline = false) {
+               if (is_string($allowNewline)) {
+                       $validChars = $allowNewline;
+               } else {
+                       $validChars = $allowNewline ? "." : "[^\n]";
+               }
+               if (!$this->match('('.$validChars.'*?)'.lessc::preg_quote($what), $m, !$until)) return false;
+               if ($until) $this->count -= strlen($what); // give back $what
+               $out = $m[1];
+               return true;
+       }
+
+       // try to match something on head of buffer
+       protected function match($regex, &$out, $eatWhitespace = null) {
+               if ($eatWhitespace === null) $eatWhitespace = $this->eatWhiteDefault;
+
+               $r = '/'.$regex.($eatWhitespace && !$this->writeComments ? '\s*' : '').'/Ais';
+               if (preg_match($r, $this->buffer, $out, null, $this->count)) {
+                       $this->count += strlen($out[0]);
+                       if ($eatWhitespace && $this->writeComments) $this->whitespace();
+                       return true;
+               }
+               return false;
+       }
+
+       // match some whitespace
+       protected function whitespace() {
+               if ($this->writeComments) {
+                       $gotWhite = false;
+                       while (preg_match(self::$whitePattern, $this->buffer, $m, null, $this->count)) {
+                               if (isset($m[1]) && empty($this->commentsSeen[$this->count])) {
+                                       $this->append(array("comment", $m[1]));
+                                       $this->commentsSeen[$this->count] = true;
+                               }
+                               $this->count += strlen($m[0]);
+                               $gotWhite = true;
+                       }
+                       return $gotWhite;
+               } else {
+                       $this->match("", $m);
+                       return strlen($m[0]) > 0;
+               }
+       }
+
+       // match something without consuming it
+       protected function peek($regex, &$out = null, $from=null) {
+               if (is_null($from)) $from = $this->count;
+               $r = '/'.$regex.'/Ais';
+               $result = preg_match($r, $this->buffer, $out, null, $from);
+
+               return $result;
+       }
+
+       // seek to a spot in the buffer or return where we are on no argument
+       protected function seek($where = null) {
+               if ($where === null) return $this->count;
+               else $this->count = $where;
+               return true;
+       }
+
+       /* misc functions */
+
+       public function throwError($msg = "parse error", $count = null) {
+               $count = is_null($count) ? $this->count : $count;
+
+               $line = $this->line +
+                       substr_count(substr($this->buffer, 0, $count), "\n");
+
+               if (!empty($this->sourceName)) {
+                       $loc = "$this->sourceName on line $line";
+               } else {
+                       $loc = "line: $line";
+               }
+
+               // TODO this depends on $this->count
+               if ($this->peek("(.*?)(\n|$)", $m, $count)) {
+                       throw new exception("$msg: failed at `$m[1]` $loc");
+               } else {
+                       throw new exception("$msg: $loc");
+               }
+       }
+
+       protected function pushBlock($selectors=null, $type=null) {
+               $b = new stdclass;
+               $b->parent = $this->env;
+
+               $b->type = $type;
+               $b->id = self::$nextBlockId++;
+
+               $b->isVararg = false; // TODO: kill me from here
+               $b->tags = $selectors;
+
+               $b->props = array();
+               $b->children = array();
+
+               $this->env = $b;
+               return $b;
+       }
+
+       // push a block that doesn't multiply tags
+       protected function pushSpecialBlock($type) {
+               return $this->pushBlock(null, $type);
+       }
+
+       // append a property to the current block
+       protected function append($prop, $pos = null) {
+               if ($pos !== null) $prop[-1] = $pos;
+               $this->env->props[] = $prop;
+       }
+
+       // pop something off the stack
+       protected function pop() {
+               $old = $this->env;
+               $this->env = $this->env->parent;
+               return $old;
+       }
+
+       // remove comments from $text
+       // todo: make it work for all functions, not just url
+       protected function removeComments($text) {
+               $look = array(
+                       'url(', '//', '/*', '"', "'"
+               );
+
+               $out = '';
+               $min = null;
+               while (true) {
+                       // find the next item
+                       foreach ($look as $token) {
+                               $pos = strpos($text, $token);
+                               if ($pos !== false) {
+                                       if (!isset($min) || $pos < $min[1]) $min = array($token, $pos);
+                               }
+                       }
+
+                       if (is_null($min)) break;
+
+                       $count = $min[1];
+                       $skip = 0;
+                       $newlines = 0;
+                       switch ($min[0]) {
+                       case 'url(':
+                               if (preg_match('/url\(.*?\)/', $text, $m, 0, $count))
+                                       $count += strlen($m[0]) - strlen($min[0]);
+                               break;
+                       case '"':
+                       case "'":
+                               if (preg_match('/'.$min[0].'.*?(?<!\\\\)'.$min[0].'/', $text, $m, 0, $count))
+                                       $count += strlen($m[0]) - 1;
+                               break;
+                       case '//':
+                               $skip = strpos($text, "\n", $count);
+                               if ($skip === false) $skip = strlen($text) - $count;
+                               else $skip -= $count;
+                               break;
+                       case '/*':
+                               if (preg_match('/\/\*.*?\*\//s', $text, $m, 0, $count)) {
+                                       $skip = strlen($m[0]);
+                                       $newlines = substr_count($m[0], "\n");
+                               }
+                               break;
+                       }
+
+                       if ($skip == 0) $count += strlen($min[0]);
+
+                       $out .= substr($text, 0, $count).str_repeat("\n", $newlines);
+                       $text = substr($text, $count + $skip);
+
+                       $min = null;
+               }
+
+               return $out.$text;
+       }
+
+}
+
+class lessc_formatter_classic {
+       public $indentChar = "  ";
+
+       public $break = "\n";
+       public $open = " {";
+       public $close = "}";
+       public $selectorSeparator = ", ";
+       public $assignSeparator = ":";
+
+       public $openSingle = " { ";
+       public $closeSingle = " }";
+
+       public $disableSingle = false;
+       public $breakSelectors = false;
+
+       public $compressColors = false;
+
+       public function __construct() {
+               $this->indentLevel = 0;
+       }
+
+       public function indentStr($n = 0) {
+               return str_repeat($this->indentChar, max($this->indentLevel + $n, 0));
+       }
+
+       public function property($name, $value) {
+               return $name . $this->assignSeparator . $value . ";";
+       }
+
+       protected function isEmpty($block) {
+               if (empty($block->lines)) {
+                       foreach ($block->children as $child) {
+                               if (!$this->isEmpty($child)) return false;
+                       }
+
+                       return true;
+               }
+               return false;
+       }
+
+       public function block($block) {
+               if ($this->isEmpty($block)) return;
+
+               $inner = $pre = $this->indentStr();
+
+               $isSingle = !$this->disableSingle &&
+                       is_null($block->type) && count($block->lines) == 1;
+
+               if (!empty($block->selectors)) {
+                       $this->indentLevel++;
+
+                       if ($this->breakSelectors) {
+                               $selectorSeparator = $this->selectorSeparator . $this->break . $pre;
+                       } else {
+                               $selectorSeparator = $this->selectorSeparator;
+                       }
+
+                       echo $pre .
+                               implode($selectorSeparator, $block->selectors);
+                       if ($isSingle) {
+                               echo $this->openSingle;
+                               $inner = "";
+                       } else {
+                               echo $this->open . $this->break;
+                               $inner = $this->indentStr();
+                       }
+
+               }
+
+               if (!empty($block->lines)) {
+                       $glue = $this->break.$inner;
+                       echo $inner . implode($glue, $block->lines);
+                       if (!$isSingle && !empty($block->children)) {
+                               echo $this->break;
+                       }
+               }
+
+               foreach ($block->children as $child) {
+                       $this->block($child);
+               }
+
+               if (!empty($block->selectors)) {
+                       if (!$isSingle && empty($block->children)) echo $this->break;
+
+                       if ($isSingle) {
+                               echo $this->closeSingle . $this->break;
+                       } else {
+                               echo $pre . $this->close . $this->break;
+                       }
+
+                       $this->indentLevel--;
+               }
+       }
+}
+
+class lessc_formatter_compressed extends lessc_formatter_classic {
+       public $disableSingle = true;
+       public $open = "{";
+       public $selectorSeparator = ",";
+       public $assignSeparator = ":";
+       public $break = "";
+       public $compressColors = true;
+
+       public function indentStr($n = 0) {
+               return "";
+       }
+}
+
+class lessc_formatter_lessjs extends lessc_formatter_classic {
+       public $disableSingle = true;
+       public $breakSelectors = true;
+       public $assignSeparator = ": ";
+       public $selectorSeparator = ",";
+}
+
+
index 10c25f0..ead81cc 100644 (file)
@@ -115,6 +115,12 @@ class ResourceLoaderFileModule extends ResourceLoaderModule {
        protected $raw = false;
        protected $targets = array( 'desktop' );
 
+       /**
+        * Boolean: Whether getStyleURLsForDebug should return raw file paths,
+        * or return load.php urls
+        */
+       protected $hasGeneratedStyles = false;
+
        /**
         * Array: Cache for mtime
         * @par Usage:
@@ -334,6 +340,13 @@ class ResourceLoaderFileModule extends ResourceLoaderModule {
         * @return array
         */
        public function getStyleURLsForDebug( ResourceLoaderContext $context ) {
+               if ( $this->hasGeneratedStyles ) {
+                       // Do the default behaviour of returning a url back to load.php
+                       // but with only=styles.
+                       return parent::getStyleURLsForDebug( $context );
+               }
+               // Our module consists entirely of real css files,
+               // in debug mode we can load those directly.
                $urls = array();
                foreach ( $this->getStyleFiles( $context ) as $mediaType => $list ) {
                        $urls[$mediaType] = array();
@@ -470,6 +483,16 @@ class ResourceLoaderFileModule extends ResourceLoaderModule {
                return "{$this->remoteBasePath}/$path";
        }
 
+       /**
+        * Infer the stylesheet language from a stylesheet file path.
+        *
+        * @param string $path
+        * @return string: the stylesheet language name
+        */
+       protected function getStyleSheetLang( $path ) {
+               return preg_match( '/\.less$/i', $path ) ? 'less' : 'css';
+       }
+
        /**
         * Collates file paths by option (where provided).
         *
@@ -632,7 +655,14 @@ class ResourceLoaderFileModule extends ResourceLoaderModule {
                        wfDebugLog( 'resourceloader', $msg );
                        throw new MWException( $msg );
                }
-               $style = file_get_contents( $localPath );
+
+               if ( $this->getStyleSheetLang( $path ) === 'less' ) {
+                       $style = $this->compileLESSFile( $localPath );
+                       $this->hasGeneratedStyles = true;
+               } else {
+                       $style = file_get_contents( $localPath );
+               }
+
                if ( $flip ) {
                        $style = CSSJanus::transform( $style, true, false );
                }
@@ -671,4 +701,82 @@ class ResourceLoaderFileModule extends ResourceLoaderModule {
                return $this->targets;
        }
 
+       /**
+        * Generate a cache key for a LESS file.
+        * The cache key varies on the file name, the names and values of global
+        * LESS variables, and the value of $wgShowExceptionDetails. Varying on
+        * $wgShowExceptionDetails ensures the CSS comment indicating compilation
+        * failure shows the right level of detail.
+        *
+        * @param string $fileName File name of root LESS file.
+        * @return string: Cache key
+        */
+       protected static function getLESSCacheKey( $fileName ) {
+               global $wgShowExceptionDetails;
+
+               $vars = json_encode( self::getLESSVars() );
+               $hash = md5( $fileName . $vars );
+               return wfMemcKey( 'resourceloader', 'less', (string)$wgShowExceptionDetails, $hash );
+       }
+
+       /**
+        * Compile a LESS file into CSS.
+        *
+        * If invalid, returns replacement CSS source consisting of the compilation
+        * error message encoded as a comment. To save work, we cache a result object
+        * which comprises the compiled CSS and the names & mtimes of the files
+        * that were processed. lessphp compares the cached & current mtimes and
+        * recompiles as necessary.
+        *
+        * @param string $fileName File path of LESS source
+        * @return string: CSS source
+        */
+       protected function compileLESSFile( $fileName ) {
+               global $wgShowExceptionDetails;
+
+               $key = self::getLESSCacheKey( $fileName );
+               $cache = wfGetCache( CACHE_ANYTHING );
+
+               // The input to lessc. Either an associative array representing the
+               // cached results of a previous compilation, or the string file name if
+               // no cache result exists.
+               $source = $cache->get( $key );
+               if ( !is_array( $source ) || !isset( $source['root'] ) ) {
+                       $source = $fileName;
+               }
+
+               $compiler = self::lessCompiler();
+               $expire = 0;
+               try {
+                       $result = $compiler->cachedCompile( $source );
+                       if ( !is_array( $result ) ) {
+                               throw new Exception( 'LESS compiler result has type ' . gettype( $result ) . '; array expected.' );
+                       }
+               } catch ( Exception $e ) {
+                       // The exception might have been caused by an imported file rather
+                       // than the root node. But we don't know which files were imported,
+                       // because compilation failed; we thus cannot rely on file mtime to
+                       // know when to reattempt compilation. Expire in 5 mins. instead.
+                       $expire = 300;
+                       wfDebugLog( 'resourceloader', __METHOD__ . ": $e" );
+                       $result = array();
+                       $result['root'] = $fileName;
+
+                       if ( $wgShowExceptionDetails ) {
+                               $result['compiled'] = ResourceLoader::makeComment( 'LESS error: ' . $e->getMessage() );
+                       } else {
+                               $result['compiled'] = ResourceLoader::makeComment( 'LESS stylesheet compilation failed. ' .
+                                       'Set "$wgShowExceptionDetails = true;" to show detailed debugging information.' );
+                       }
+
+                       $result['files'] = array( $fileName => self::safeFilemtime( $fileName ) );
+                       $result['updated'] = time();
+               }
+               // Tie cache expiry to the names and mtimes of image files that were
+               // embedded in the generated CSS source.
+               $result['files'] += $compiler->embeddedImages;
+               $this->localFileRefs += array_keys( $result['files'] );
+               $cache->set( $key, $result, $expire );
+               return $result['compiled'];
+       }
 }
index 298f1fe..226d91c 100644 (file)
@@ -407,6 +407,9 @@ abstract class ResourceLoaderModule {
        private static $jsParser;
        private static $parseCacheVersion = 1;
 
+       /** @var array Global LESS variables */
+       private static $lessVars;
+
        /**
         * Validate a given script file; if valid returns the original source.
         * If invalid, returns replacement JS source that throws an exception.
@@ -454,6 +457,42 @@ abstract class ResourceLoaderModule {
                return self::$jsParser;
        }
 
+       /**
+        * @return lessc
+        */
+       protected static function lessCompiler() {
+               global $wgResourceLoaderLESSFunctions, $wgResourceLoaderLESSImportPaths;
+
+               $less = new lessc();
+               $less->setPreserveComments( true );
+               $less->setVariables( self::getLESSVars() );
+               $less->setImportDir( $wgResourceLoaderLESSImportPaths );
+               foreach ( $wgResourceLoaderLESSFunctions as $name => $func ) {
+                       $less->registerFunction( $name, $func );
+               }
+               // To ensure embedded images are refreshed when their source files
+               // change, track the names and modification times of image files that
+               // were embedded in the generated CSS source.
+               $less->embeddedImages = array();
+               return $less;
+       }
+
+       /**
+        * Get global LESS variables.
+        *
+        * @return array: Map of variable names to string CSS values.
+        */
+       protected static function getLESSVars() {
+               global $wgResourceLoaderLESSVars;
+
+               if ( self::$lessVars === null ) {
+                       self::$lessVars = $wgResourceLoaderLESSVars;
+                       // Sort by key to ensure consistent hashing for cache lookups.
+                       ksort( self::$lessVars );
+               }
+               return self::$lessVars;
+       }
+
        /**
         * Safe version of filemtime(), which doesn't throw a PHP warning if the file doesn't exist
         * but returns 1 instead.
diff --git a/resources/mediawiki.less/mediawiki.mixins.less b/resources/mediawiki.less/mediawiki.mixins.less
new file mode 100644 (file)
index 0000000..c0a1104
--- /dev/null
@@ -0,0 +1,13 @@
+/**
+ * Common LESS mixin library for MediaWiki
+ *
+ * By default the folder containing this file is included in $wgResourceLoaderLESSImportPaths,
+ * which makes this file importable by all less files via '@import "mediawiki.mixins";'.
+ *
+ * The mixins included below are considered a public interface for MediaWiki extensions.
+ * The signatures of parametrized mixins should be kept as stable as possible.
+ *
+ * See <http://lesscss.org/#-mixins> for more information about how to write mixins.
+ */
+
+// No mixins yet!
diff --git a/tests/phpunit/data/less/common/test.common.mixins.less b/tests/phpunit/data/less/common/test.common.mixins.less
new file mode 100644 (file)
index 0000000..2fbe9b7
--- /dev/null
@@ -0,0 +1,5 @@
+.test-mixin (@value) {
+       color: @value;
+       border: @foo solid @Foo;
+       line-height: test-sum(@bar, 10, 20);
+}
diff --git a/tests/phpunit/data/less/module/dependency.less b/tests/phpunit/data/less/module/dependency.less
new file mode 100644 (file)
index 0000000..c7725a2
--- /dev/null
@@ -0,0 +1,3 @@
+@import "test.common.mixins";
+
+@unitTestColor: green;
diff --git a/tests/phpunit/data/less/module/styles.css b/tests/phpunit/data/less/module/styles.css
new file mode 100644 (file)
index 0000000..b78780a
--- /dev/null
@@ -0,0 +1,6 @@
+/* @noflip */
+.unit-tests {
+  color: green;
+  border: 2px solid #eeeeee;
+  line-height: 35;
+}
diff --git a/tests/phpunit/data/less/module/styles.less b/tests/phpunit/data/less/module/styles.less
new file mode 100644 (file)
index 0000000..ecac839
--- /dev/null
@@ -0,0 +1,6 @@
+@import "dependency";
+
+/* @noflip */
+.unit-tests {
+       .test-mixin(@unitTestColor);
+}
index fa228a6..c30c441 100644 (file)
@@ -4,6 +4,32 @@ class ResourceLoaderTest extends MediaWikiTestCase {
 
        protected static $resourceLoaderRegisterModulesHook;
 
+       protected function setUp() {
+               parent::setUp();
+
+               // $wgResourceLoaderLESSFunctions, $wgResourceLoaderLESSImportPaths; $wgResourceLoaderLESSVars;
+
+               $this->setMwGlobals( array(
+                       'wgResourceLoaderLESSFunctions' => array(
+                               'test-sum' => function ( $frame, $less ) {
+                                       $sum = 0;
+                                       foreach ( $frame[2] as $arg ) {
+                                               $sum += (int)$arg[1];
+                                       }
+                                       return $sum;
+                               },
+                       ),
+                       'wgResourceLoaderLESSImportPaths' => array(
+                               dirname( __DIR__ ) . '/data/less/common',
+                       ),
+                       'wgResourceLoaderLESSVars' => array(
+                               'foo'  => '2px',
+                               'Foo' => '#eeeeee',
+                               'bar' => 5,
+                       ),
+               ) );
+       }
+
        /* Hook Methods */
 
        /**
@@ -22,6 +48,14 @@ class ResourceLoaderTest extends MediaWikiTestCase {
                );
        }
 
+       public static function provideResourceLoaderContext() {
+               $resourceLoader = new ResourceLoader();
+               $request = new FauxRequest();
+               return array(
+                       array( new ResourceLoaderContext( $resourceLoader, $request ) ),
+               );
+       }
+
        /* Test Methods */
 
        /**
@@ -49,6 +83,20 @@ class ResourceLoaderTest extends MediaWikiTestCase {
                $this->assertEquals( $module, $resourceLoader->getModule( $name ) );
        }
 
+       /**
+        * @dataProvider provideResourceLoaderContext
+        * @covers ResourceLoaderFileModule::compileLessFile
+        */
+       public function testLessFileCompilation( $context ) {
+               $basePath = __DIR__ . '/../data/less/module';
+               $module = new ResourceLoaderFileModule( array(
+                       'localBasePath' => $basePath,
+                       'styles' => array( 'styles.less' ),
+               ) );
+               $styles = $module->getStyles( $context );
+               $this->assertStringEqualsFile( $basePath . '/styles.css', $styles['all'] );
+       }
+
        /**
         * @dataProvider providePackedModules
         */