node.rb in radiantcms-couchrest_model-0.1.4

- old
+ new

@@ -1,47 +1,30 @@
 module Sass
   # A namespace for nodes in the Sass parse tree.
   #
-  # The Sass parse tree has three states: dynamic, static Sass, and static CSS.
-  #
-  # When it's first parsed, a Sass document is in the dynamic state.
-  # It has nodes for mixin definitions and `@for` loops and so forth,
+  # The Sass parse tree has two states.
+  # When it's first parsed, it has nodes for mixin definitions
+  # and for loops and so forth,
   # in addition to nodes for CSS rules and properties.
-  # Nodes that only appear in this state are called **dynamic nodes**.
   #
-  # {Tree::Node#perform} returns a static Sass tree, which is different.
-  # It still has nodes for CSS rules and properties
+  # However, {Tree::Node#perform} returns a different sort of tree.
+  # This tree maps more closely to the resulting CSS document
+  # than it does to the original Sass document.
+  # It still has nodes for CSS rules and properties,
   # but it doesn't have any dynamic-generation-related nodes.
-  # The nodes in this state are in the same structure as the Sass document:
-  # rules and properties are nested beneath one another.
-  # Nodes that can be in this state or in the dynamic state
-  # are called **static nodes**.
   #
-  # {Tree::Node#cssize} then returns a static CSS tree.
-  # This is like a static Sass tree,
-  # but the structure exactly mirrors that of the generated CSS.
-  # Rules and properties can't be nested beneath one another in this state.
-  #
-  # Finally, {Tree::Node#to_s} can be called on a static CSS tree
-  # to get the actual CSS code as a string.
+  # Nodes that only appear in the pre-perform state are called **dynamic nodes**;
+  # those that appear in both states are called **static nodes**.
   module Tree
-    # The abstract superclass of all parse-tree nodes.
+    # This class doubles as the root node of the parse tree
+    # and the superclass of all other parse-tree nodes.
     class Node
-      include Enumerable
-
       # The child nodes of this node.
       #
       # @return [Array<Tree::Node>]
       attr_accessor :children
 
-      # Whether or not this node has child nodes.
-      # This may be true even when \{#children} is empty,
-      # in which case this node has an empty block (e.g. `{}`).
-      #
-      # @return [Boolean]
-      attr_accessor :has_children
-
       # The line of the document on which this node appeared.
       #
       # @return [Fixnum]
       attr_accessor :line
 
@@ -67,48 +50,36 @@
       def options=(options)
         children.each {|c| c.options = options}
         @options = options
       end
 
-      # @private
-      def children=(children)
-        self.has_children ||= !children.empty?
-        @children = children
-      end
-
       # The name of the document on which this node appeared.
       #
       # @return [String]
       def filename
         @filename || (@options && @options[:filename])
       end
 
       # Appends a child to the node.
       #
-      # @param child [Tree::Node, Array<Tree::Node>] The child node or nodes
+      # @param child [Tree::Node] The child node
       # @raise [Sass::SyntaxError] if `child` is invalid
       # @see #invalid_child?
       def <<(child)
-        return if child.nil?
-        if child.is_a?(Array)
-          child.each {|c| self << c}
-        else
-          check_child! child
-          self.has_children = true
-          @children << child
+        if msg = invalid_child?(child)
+          raise Sass::SyntaxError.new(msg, child.line)
         end
+        @children << child
       end
 
-      # Raises an error if the given child node is invalid.
+      # Return the last child node.
       #
-      # @param child [Tree::Node] The child node
-      # @raise [Sass::SyntaxError] if `child` is invalid
-      # @see #invalid_child?
-      def check_child!(child)
-        if msg = invalid_child?(child)
-          raise Sass::SyntaxError.new(msg, :line => child.line)
-        end
+      # We need this because {Tree::Node} duck types as an Array for {Sass::Engine}.
+      #
+      # @return [Tree::Node] The last child node
+      def last
+        children.last
       end
 
       # Compares this node and another object (only other {Tree::Node}s will be equal).
       # This does a structural comparison;
       # if the contents of the nodes and all the child nodes are equivalent,
@@ -122,178 +93,83 @@
       # @see Sass::Tree
       def ==(other)
         self.class == other.class && other.children == children
       end
 
+      # Runs the dynamic Sass code *and* computes the CSS for the tree.
+      #
+      # @see #perform
+      # @see #to_s
+      def render
+        perform(Environment.new).to_s
+      end
+
       # True if \{#to\_s} will return `nil`;
       # that is, if the node shouldn't be rendered.
       # Should only be called in a static tree.
       #
       # @return [Boolean]
       def invisible?; false; end
 
-      # The output style. See {file:SASS_REFERENCE.md#sass_options the Sass options documentation}.
+      # Computes the CSS corresponding to this Sass tree.
       #
-      # @return [Symbol]
-      def style
-        @options[:style]
-      end
-
-      # Computes the CSS corresponding to this static CSS tree.
-      #
-      # \{#to_s} shouldn't be overridden directly; instead, override \{#\_to\_s}.
       # Only static-node subclasses need to implement \{#to\_s}.
       #
       # This may return `nil`, but it will only do so if \{#invisible?} is true.
       #
-      # @param args [Array] Passed on to \{#\_to\_s}
       # @return [String, nil] The resulting CSS
-      # @see Sass::Tree
-      def to_s(*args)
-        _to_s(*args)
-      rescue Sass::SyntaxError => e
-        e.modify_backtrace(:filename => filename, :line => line)
-        raise e
-      end
-
-      # Converts a static CSS tree (e.g. the output of \{#cssize})
-      # into another static CSS tree,
-      # with the given extensions applied to all relevant {RuleNode}s.
-      #
-      # @todo Link this to the reference documentation on `@extend`
-      #   when such a thing exists.
-      #
-      # @param extends [Haml::Util::SubsetMap{Selector::Simple => Selector::Sequence}]
-      #   The extensions to perform on this tree
-      # @return [Tree::Node] The resulting tree of static CSS nodes.
-      # @raise [Sass::SyntaxError] Only if there's a programmer error
-      #   and this is not a static CSS tree
-      def do_extend(extends)
-        node = dup
-        node.children = children.map {|c| c.do_extend(extends)}
-        node
-      rescue Sass::SyntaxError => e
-        e.modify_backtrace(:filename => filename, :line => line)
-        raise e
-      end
-
-      # Converts a static Sass tree (e.g. the output of \{#perform})
-      # into a static CSS tree.
-      #
-      # \{#cssize} shouldn't be overridden directly;
-      # instead, override \{#\_cssize} or \{#cssize!}.
-      #
-      # @param extends [Haml::Util::SubsetMap{Selector::Simple => Selector::Sequence}]
-      #   The extensions defined for this tree
-      # @param parent [Node, nil] The parent node of this node.
-      #   This should only be non-nil if the parent is the same class as this node
-      # @return [Tree::Node] The resulting tree of static nodes
       # @raise [Sass::SyntaxError] if some element of the tree is invalid
       # @see Sass::Tree
-      def cssize(extends, parent = nil)
-        _cssize(extends, (parent if parent.class == self.class))
-      rescue Sass::SyntaxError => e
-        e.modify_backtrace(:filename => filename, :line => line)
-        raise e
+      def to_s
+        result = String.new
+        children.each do |child|
+          if child.is_a? PropNode
+            message = "Properties aren't allowed at the root of a document." +
+              child.pseudo_class_selector_message
+            raise Sass::SyntaxError.new(message, child.line)
+          else
+            next if child.invisible?
+            child_str = child.to_s(1)
+            result << child_str + (style == :compressed ? '' : "\n")
+          end
+        end
+        result.rstrip!
+        return "" if result.empty?
+        return result + "\n"
+      rescue Sass::SyntaxError => e; e.add_metadata(filename, line)
       end
 
-      # Converts a dynamic tree into a static Sass tree.
-      # That is, runs the dynamic Sass code:
+      # Runs the dynamic Sass code:
       # mixins, variables, control directives, and so forth.
       # This doesn't modify this node or any of its children.
       #
       # \{#perform} shouldn't be overridden directly;
-      # instead, override \{#\_perform} or \{#perform!}.
+      # if you want to return a new node (or list of nodes),
+      # override \{#\_perform};
+      # if you want to destructively modify this node,
+      # override \{#perform!}.
       #
       # @param environment [Sass::Environment] The lexical environment containing
       #   variable and mixin values
       # @return [Tree::Node] The resulting tree of static nodes
       # @raise [Sass::SyntaxError] if some element of the tree is invalid
       # @see Sass::Tree
       def perform(environment)
+        environment.options = @options if self.class == Tree::Node
         _perform(environment)
-      rescue Sass::SyntaxError => e
-        e.modify_backtrace(:filename => filename, :line => line)
-        raise e
+      rescue Sass::SyntaxError => e; e.add_metadata(filename, line)
       end
 
-      # Iterates through each node in the tree rooted at this node
-      # in a pre-order walk.
+      # The output style. See {file:SASS_REFERENCE.md#sass_options the Sass options documentation}.
       #
-      # @yield node
-      # @yieldparam node [Node] a node in the tree
-      def each(&block)
-        yield self
-        children.each {|c| c.each(&block)}
+      # @return [Symbol]
+      def style
+        @options[:style]
       end
 
-      # Converts a node to Sass code that will generate it.
-      #
-      # @param tabs [Fixnum] The amount of tabulation to use for the Sass code
-      # @param opts [{Symbol => Object}] An options hash (see {Sass::CSS#initialize})
-      # @return [String] The Sass code corresponding to the node
-      def to_sass(tabs = 0, opts = {})
-        to_src(tabs, opts, :sass)
-      end
-
-      # Converts a node to SCSS code that will generate it.
-      #
-      # @param tabs [Fixnum] The amount of tabulation to use for the SCSS code
-      # @param opts [{Symbol => Object}] An options hash (see {Sass::CSS#initialize})
-      # @return [String] The Sass code corresponding to the node
-      def to_scss(tabs = 0, opts = {})
-        to_src(tabs, opts, :scss)
-      end
-
       protected
 
-      # Computes the CSS corresponding to this particular Sass node.
-      #
-      # This method should never raise {Sass::SyntaxError}s.
-      # Such errors will not be properly annotated with Sass backtrace information.
-      # All error conditions should be checked in earlier transformations,
-      # such as \{#cssize} and \{#perform}.
-      #
-      # @param args [Array] ignored
-      # @return [String, nil] The resulting CSS
-      # @see #to_s
-      # @see Sass::Tree
-      def _to_s
-        raise NotImplementedError.new("All static-node subclasses of Sass::Tree::Node must override #_to_s or #to_s.")
-      end
-
-      # Converts this static Sass node into a static CSS node,
-      # returning the new node.
-      # This doesn't modify this node or any of its children.
-      #
-      # @param extends [Haml::Util::SubsetMap{Selector::Simple => Selector::Sequence}]
-      #   The extensions defined for this tree
-      # @param parent [Node, nil] The parent node of this node.
-      #   This should only be non-nil if the parent is the same class as this node
-      # @return [Tree::Node, Array<Tree::Node>] The resulting static CSS nodes
-      # @raise [Sass::SyntaxError] if some element of the tree is invalid
-      # @see #cssize
-      # @see Sass::Tree
-      def _cssize(extends, parent)
-        node = dup
-        node.cssize!(extends, parent)
-        node
-      end
-
-      # Destructively converts this static Sass node into a static CSS node.
-      # This *does* modify this node,
-      # but will be run non-destructively by \{#\_cssize\}.
-      #
-      # @param extends [Haml::Util::SubsetMap{Selector::Simple => Selector::Sequence}]
-      #   The extensions defined for this tree
-      # @param parent [Node, nil] The parent node of this node.
-      #   This should only be non-nil if the parent is the same class as this node
-      # @see #cssize
-      def cssize!(extends, parent)
-        self.children = children.map {|c| c.cssize(extends, self)}.flatten
-      end
-
       # Runs any dynamic Sass code in this particular node.
       # This doesn't modify this node or any of its children.
       #
       # @param environment [Sass::Environment] The lexical environment containing
       #   variable and mixin values
@@ -324,142 +200,52 @@
       # @return [Array<Tree::Node>] The resulting static nodes
       def perform_children(environment)
         children.map {|c| c.perform(environment)}.flatten
       end
 
-      # Replaces SassScript in a chunk of text
+      # Replaces SassScript in a chunk of text (via `#{}`)
       # with the resulting value.
       #
-      # @param text [Array<String, Sass::Script::Node>] The text to interpolate
+      # @param text [String] The text to interpolate
       # @param environment [Sass::Environment] The lexical environment containing
       #   variable and mixin values
       # @return [String] The interpolated text
-      def run_interp(text, environment)
-        text.map do |r|
-          next r if r.is_a?(String)
-          val = r.perform(environment)
-          # Interpolated strings should never render with quotes
-          next val.value if val.is_a?(Sass::Script::String)
-          val.to_s
-        end.join.strip
+      def interpolate(text, environment)
+        res = ''
+        rest = Haml::Shared.handle_interpolation text do |scan|
+          escapes = scan[2].size
+          res << scan.matched[0...-2 - escapes]
+          if escapes % 2 == 1
+            res << "\\" * (escapes - 1) << '#{'
+          else
+            res << "\\" * [0, escapes - 1].max
+            res << Script::Parser.new(scan, line, scan.pos - scan.matched_size, filename).
+              parse_interpolated.perform(environment).to_s
+          end
+        end
+        res + rest
       end
 
       # @see Haml::Shared.balance
       # @raise [Sass::SyntaxError] if the brackets aren't balanced
       def balance(*args)
         res = Haml::Shared.balance(*args)
         return res if res
-        raise Sass::SyntaxError.new("Unbalanced brackets.", :line => line)
+        raise Sass::SyntaxError.new("Unbalanced brackets.", line)
       end
 
       # Returns an error message if the given child node is invalid,
       # and false otherwise.
       #
-      # By default, all child nodes except those only allowed under specific nodes
-      # ({Tree::MixinDefNode}, {Tree::ImportNode}, {Tree::ExtendNode}) are valid.
+      # By default, all child nodes are valid.
       # This is expected to be overriden by subclasses
       # for which some children are invalid.
       #
       # @param child [Tree::Node] A potential child node
       # @return [Boolean, String] Whether or not the child node is valid,
       #   as well as the error message to display if it is invalid
       def invalid_child?(child)
-        case child
-        when Tree::MixinDefNode
-          "Mixins may only be defined at the root of a document."
-        when Tree::ImportNode
-          "Import directives may only be used at the root of a document."
-        when Tree::ExtendNode
-          "Extend directives may only be used within rules."
-        end
-      end
-
-      # Converts a node to Sass or SCSS code that will generate it.
-      #
-      # This method is called by the default \{#to\_sass} and \{#to\_scss} methods,
-      # so that the same code can be used for both with minor variations.
-      #
-      # @param tabs [Fixnum] The amount of tabulation to use for the SCSS code
-      # @param opts [{Symbol => Object}] An options hash (see {Sass::CSS#initialize})
-      # @param fmt [Symbol] `:sass` or `:scss`
-      # @return [String] The Sass or SCSS code corresponding to the node
-      def to_src(tabs, opts, fmt)
-        raise NotImplementedError.new("All static-node subclasses of Sass::Tree::Node must override #to_#{fmt}.")
-      end
-
-      # Converts the children of this node to a Sass or SCSS string.
-      # This will return the trailing newline for the previous line,
-      # including brackets if this is SCSS.
-      #
-      # @param tabs [Fixnum] The amount of tabulation to use for the Sass code
-      # @param opts [{Symbol => Object}] An options hash (see {Sass::CSS#initialize})
-      # @param fmt [Symbol] `:sass` or `:scss`
-      # @return [String] The Sass or SCSS code corresponding to the children
-      def children_to_src(tabs, opts, fmt)
-        return fmt == :sass ? "\n" : " {}\n" if children.empty?
-
-        (fmt == :sass ? "\n" : " {\n") +
-          children.map {|c| c.send("to_#{fmt}", tabs + 1, opts)}.join.rstrip +
-          (fmt == :sass ? "\n" : " }\n")
-      end
-
-      # Converts a selector to a Sass or SCSS string.
-      #
-      # @param sel [Array<String, Sass::Script::Node>] The selector to convert
-      # @param tabs [Fixnum] The indentation of the selector
-      # @param opts [{Symbol => Object}] An options hash (see {Sass::CSS#initialize})
-      # @param fmt [Symbol] `:sass` or `:scss`
-      # @return [String] The Sass or SCSS code corresponding to the selector
-      def selector_to_src(sel, tabs, opts, fmt)
-        fmt == :sass ? selector_to_sass(sel, opts) : selector_to_scss(sel, tabs, opts)
-      end
-
-      # Converts a selector to a Sass string.
-      #
-      # @param sel [Array<String, Sass::Script::Node>] The selector to convert
-      # @param opts [{Symbol => Object}] An options hash (see {Sass::CSS#initialize})
-      # @return [String] The Sass code corresponding to the selector
-      def selector_to_sass(sel, opts)
-        sel.map do |r|
-          if r.is_a?(String)
-            r.gsub(/(,[ \t]*)?\n\s*/) {$1 ? $1 + "\n" : " "}
-          else
-            "\#{#{r.to_sass(opts)}}"
-          end
-        end.join
-      end
-
-      # Converts a selector to a SCSS string.
-      #
-      # @param sel [Array<String, Sass::Script::Node>] The selector to convert
-      # @param tabs [Fixnum] The indentation of the selector
-      # @param opts [{Symbol => Object}] An options hash (see {Sass::CSS#initialize})
-      # @return [String] The SCSS code corresponding to the selector
-      def selector_to_scss(sel, tabs, opts)
-        sel.map {|r| r.is_a?(String) ? r : "\#{#{r.to_sass(opts)}}"}.
-          join.gsub(/^[ \t]*/, '  ' * tabs)
-      end
-
-      # Convert any underscores in a string into hyphens,
-      # but only if the `:dasherize` option is set.
-      #
-      # @param s [String] The string to convert
-      # @param opts [{Symbol => Object}] The options hash
-      # @return [String] The converted string
-      def dasherize(s, opts)
-        if opts[:dasherize]
-          s.gsub('_', '-')
-        else
-          s
-        end
-      end
-
-      # Returns a semicolon if this is SCSS, or an empty string if this is Sass.
-      #
-      # @param fmt [Symbol] `:sass` or `:scss`
-      # @return [String] A semicolon or the empty string
-      def semi(fmt)
-        fmt == :sass ? "" : ";"
+        false
       end
     end
   end
 end