Added media query support.

* env.dumpLineNumbers was being lost when doing "offline" compilation
   (within node.js)
 * Added documentation for the changed options
 * --line-numbers now takes a parameter
   (either "comments", "mediaquery" or "all")
 * The system can now again output mediaqueries for FireLESS
 * Moved comments tests in debug/comments, will duplicate
   for mediaquery and for "all"

Everything is still utterly broken though, tests still fail.

bin/lessc

@@ -75,7 +75,7 @@ args = args.filter(function (arg) {
         case 'O1': options.optimization = 1; break;
         case 'O2': options.optimization = 2; break;
         case 'line-numbers':
-            options.dumpLineNumbers = true;
+            options.dumpLineNumbers = match[2];
             break;
     }
 });

lib/less/browser.js

@@ -35,8 +35,9 @@ if (less.env === 'development') {
     if (/!watch/.test(location.hash)) {
         less.watch();
     }
-    if (/!dumpLineNumbers/.test(location.hash)) {
-        less.dumpLineNumbers = true;
+    var dumpLineNumbers = /!dumpLineNumbers:(comments|mediaquery|all)/.exec(location.hash);
+    if (dumpLineNumbers) {
+        less.dumpLineNumbers = dumpLineNumbers[1];
     }
     less.watchTimer = setInterval(function () {
         if (less.watchMode) {

lib/less/index.js

@@ -119,7 +119,8 @@ less.Parser.importer = function (file, paths, callback, env) {
             new(less.Parser)({
                 paths: [path.dirname(pathname)].concat(paths),
                 filename: pathname,
-                contents: env.contents
+                contents: env.contents,
+                dumpLineNumbers: env.dumpLineNumbers
             }).parse(data, function (e, root) {
                 callback(e, root);
             });

lib/less/lessc_helper.js

@@ -41,6 +41,12 @@ var lessc_helper = {
         sys.puts("                          the number, the less nodes it will create in the");
         sys.puts("                          tree. This could matter for debugging, or if you");
         sys.puts("                          want to access the individual nodes in the tree.");
+        sys.puts("  --line-numbers=TYPE     Outputs filename and line numbers.");
+        sys.puts("                          TYPE can be either 'comments', which will output");
+        sys.puts("                          the debug info within comments, 'mediaquery'");
+        sys.puts("                          that will output the information within a fake");
+        sys.puts("                          media query which is compatible with the SASS");
+        sys.puts("                          format, and 'all' which will do both.");
         sys.puts("");
         sys.puts("Report bugs to: http://github.com/cloudhead/less.js/issues");
         sys.puts("Home page: <http://lesscss.org/>");

lib/less/tree/ruleset.js

@@ -133,7 +133,9 @@ tree.Ruleset.prototype = {
             rulesets = [], // node.Ruleset instances
             paths = [],    // Current selectors
             selector,      // The fully rendered selector
-            lineNumbersComment,      // A comment with line number for debugging.
+            lineNumbersInfo,      // Line number debugging, either as comment or fake media query.
+            lineNumbersComment, // Line number debug info as comment
+            lineNumbersMediaQuery, // Line number debug info as media query
             rule;
 
         if (! this.root) {
@@ -172,9 +174,24 @@ tree.Ruleset.prototype = {
             css.push(rules.join(env.compress ? '' : '\n'));
         } else {
             if (rules.length > 0) {
-                lineNumbersComment = "";
-                if (env.dumpLineNumbers && !env.compress)
+                lineNumbersInfo = "";
+                lineNumbersComment = '';
+                lineNumbersMediaQuery = '';
+                if (env.dumpLineNumbers && !env.compress) {
                     lineNumbersComment = '/* line ' + this.sourceLineNumber + ', ' + env.filename + ' */\n';
+                    lineNumbersMediaQuery = '@media -sass-debug-info{filename{font-family:"' + env.filename + '";}line{font-family:"' + this.sourceLineNumber + '";}}\n';
+                    switch(env.dumpLineNumbers) {
+                        case 'comments':
+                            lineNumbersInfo = lineNumbersComment;
+                            break;
+                        case 'mediaquery':
+                            lineNumbersInfo = lineNumbersMediaQuery;
+                            break;
+                        case 'all':
+                            lineNumbersInfo = lineNumbersComment+lineNumbersMediaQuery;
+                            break;
+                    }
+                }
                 selector = paths.map(function (p) {
                     return p.map(function (s) {
                         return s.toCSS(env);
@@ -189,7 +206,7 @@ tree.Ruleset.prototype = {
                 }
                 rules = _rules;
 
-                css.push(lineNumbersComment + selector + 
+                css.push(lineNumbersInfo + selector + 
                         (env.compress ? '{' : ' {\n  ') +
                         rules.join(env.compress ? '' : '\n  ') +
                         (env.compress ? '}' : '\n}\n'));

test/less-test.js

@@ -46,7 +46,7 @@ runTestSet(null, "errors/", function(name, err, compiledLess) {
         sys.puts("");
     });});
     
-runTestSet({dumpLineNumbers: true}, "debug/");
+runTestSet({dumpLineNumbers: 'comments'}, "debug/comments/");
     
 function runTestSet(options, foldername, verifyFunction) {
     foldername = foldername || "";