Added multiline selector support to Sass. Thanks to Max Muermann for pointing this out.

git-svn-id: svn://hamptoncatlin.com/haml/trunk@579 7063305b-7217-0410-af8c-cdc13e5119b9

lib/sass.rb

@@ -75,6 +75,15 @@ $LOAD_PATH << dir unless $LOAD_PATH.include?(dir)
 #     <attribute>
 #     ...
 #
+# Like CSS, you can stretch rules over multiple lines.
+# However, unlike CSS, you can only do this if each line but the last
+# ends with a comma.
+# For example:
+#
+#   .users #userTab,
+#   .posts #postsTab
+#     <attributes>
+#
 # === Attributes
 #
 # There are two different ways to write CSS attrbibutes.

lib/sass/tree/node.rb

@@ -22,17 +22,28 @@ module Sass
         children.each do |child|
           if child.is_a? AttrNode
             raise SyntaxError.new('Attributes aren\'t allowed at the root of a document.', child.line)
-          end
-
-          begin
-            result += "#{child.to_s(1)}\n"
-          rescue SyntaxError => e
-            raise e
+          elsif child.is_a?(RuleNode) && child.continued?
+            check_multiline_rule(child)
+            result << child.to_s(1)
+          else
+            begin
+              result << "#{child.to_s(1)}\n"
+            rescue SyntaxError => e
+              raise e
+            end
           end
         end
         result[0...-1]
       end
 
+      protected
+
+      def check_multiline_rule(rule)
+        unless rule.children.empty?
+          raise SyntaxError.new('Rules can\'t end in commas.', rule.line)
+        end
+      end
+
       private
 
       # This method should be overridden by subclasses to return an error message

lib/sass/tree/rule_node.rb

@@ -8,10 +8,18 @@ module Sass::Tree
 
     alias_method :rule, :value
     alias_method :rule=, :value=
+
+    def continued?
+      rule[-1] == ?,
+    end
     
     def to_s(tabs, super_rules = nil)
       attributes = []
       sub_rules = []
+
+      # Save this because the comma's removed by the super_rule additions
+      was_continued = continued?
+
       total_rule = if super_rules
         super_rules.split(/,\s*/).collect! do |s|
           self.rule.split(/,\s*/).collect do |r|
@@ -21,7 +29,7 @@ module Sass::Tree
               "#{s} #{r}"
             end
           end.join(", ")
-        end.join(", ")
+        end.join(", ") + (was_continued ? ',' : '')
       elsif self.rule.include?(PARENT)
         raise Sass::SyntaxError.new("Base-level rules cannot contain the parent-selector-referencing character '#{PARENT}'", line)
       else
@@ -37,7 +45,7 @@ module Sass::Tree
       end
       
       to_return = ''
-      unless attributes.empty?
+      if !attributes.empty?
         if @style == :compact
           to_return << "#{total_rule} { #{attributes.join(' ')} }\n"
         else
@@ -49,10 +57,18 @@ module Sass::Tree
           end_attrs = (@style == :expanded ? "\n" : ' ')
           to_return << "#{old_spaces}#{total_rule} {\n#{spaces}#{attributes}#{end_attrs}}\n"
         end
+      elsif continued?
+        to_return << total_rule + (@style == :compact ? ' ' : "\n")
       end
       
       tabs += 1 unless attributes.empty?
-      sub_rules.each { |sub| to_return << sub.to_s(tabs, total_rule) }
+      sub_rules.each do |sub|
+        if sub.continued?
+          check_multiline_rule(sub)
+        end
+
+        to_return << sub.to_s(tabs, total_rule)
+      end
       to_return
     end
   end

test/sass/engine_test.rb

@@ -39,6 +39,7 @@ class SassEngineTest < Test::Unit::TestCase
     "!a = 1b + 2c" => "Incompatible units: b and c",
     "& a\n  :b c" => "Base-level rules cannot contain the parent-selector-referencing character '&'",
     "a\n  :b\n    c" => "Illegal nesting: Only attributes may be nested beneath attributes.",
+    "a,\n  :b c" => "Rules can\'t end in commas.",
     "!a = b\n  :c d\n" => "Illegal nesting: Nothing may be nested beneath constants.",
     "@import foo.sass" => "File to import not found or unreadable: foo.sass",
     "@import templates/basic\n  foo" => "Illegal nesting: Nothing may be nested beneath import directives.",
@@ -99,6 +100,15 @@ class SassEngineTest < Test::Unit::TestCase
     assert_equal("foo {\n  bar: url(foo.png); }\n",
                  render("foo\n  bar = url(foo.png)\n"));
   end
+
+  def test_multiline_selector
+    assert_equal("#foo #bar,\n#baz #boom {\n  foo: bar; }\n",
+                 render("#foo #bar,\n#baz #boom\n  :foo bar"))
+    assert_equal("#foo #bar,\n#foo #baz {\n  foo: bar; }\n",
+                 render("#foo\n  #bar,\n  #baz\n    :foo bar"))
+    assert_equal("#foo #bar, #baz #boom { foo: bar; }\n",
+                 render("#foo #bar,\n#baz #boom\n  :foo bar", :style => :compact))
+  end
   
   private