parser.rb in radiantcms-couchrest_model-0.1.4

- old
+ new

@@ -3,27 +3,20 @@
 module Sass
   module Script
     # The parser for SassScript.
     # It parses a string of code into a tree of {Script::Node}s.
     class Parser
-      # The line number of the parser's current position.
-      #
-      # @return [Fixnum]
-      def line
-        @lexer.line
-      end
-
       # @param str [String, StringScanner] The source text to parse
       # @param line [Fixnum] The line on which the SassScript appears.
       #   Used for error reporting
       # @param offset [Fixnum] The number of characters in on which the SassScript appears.
       #   Used for error reporting
-      # @param options [{Symbol => Object}] An options hash;
-      #   see {file:SASS_REFERENCE.md#sass_options the Sass options documentation}
-      def initialize(str, line, offset, options = {})
-        @options = options
-        @lexer = lexer_class.new(str, line, offset, options)
+      # @param filename [String] The name of the file in which the SassScript appears.
+      #   Used for error reporting
+      def initialize(str, line, offset, filename = nil)
+        @filename = filename
+        @lexer = Lexer.new(str, line, offset, filename)
       end
 
       # Parses a SassScript expression within an interpolated segment (`#{}`).
       # This means that it stops when it comes across an unmatched `}`,
       # which signals the end of an interpolated segment,
@@ -32,48 +25,23 @@
       # @return [Script::Node] The root node of the parse tree
       # @raise [Sass::SyntaxError] if the expression isn't valid SassScript
       def parse_interpolated
         expr = assert_expr :expr
         assert_tok :end_interpolation
-        expr.options = @options
         expr
-      rescue Sass::SyntaxError => e
-        e.modify_backtrace :line => @lexer.line, :filename => @options[:filename]
-        raise e
       end
 
       # Parses a SassScript expression.
       #
       # @return [Script::Node] The root node of the parse tree
       # @raise [Sass::SyntaxError] if the expression isn't valid SassScript
       def parse
         expr = assert_expr :expr
         assert_done
-        expr.options = @options
         expr
-      rescue Sass::SyntaxError => e
-        e.modify_backtrace :line => @lexer.line, :filename => @options[:filename]
-        raise e
       end
 
-      # Parses a SassScript expression,
-      # ending it when it encounters one of the given identifier tokens.
-      #
-      # @param [#include?(String)] A set of strings that delimit the expression.
-      # @return [Script::Node] The root node of the parse tree
-      # @raise [Sass::SyntaxError] if the expression isn't valid SassScript
-      def parse_until(tokens)
-        @stop_at = tokens
-        expr = assert_expr :expr
-        assert_done
-        expr.options = @options
-        expr
-      rescue Sass::SyntaxError => e
-        e.modify_backtrace :line => @lexer.line, :filename => @options[:filename]
-        raise e
-      end
-
       # Parses the argument list for a mixin include.
       #
       # @return [Array<Script::Node>] The root nodes of the arguments.
       # @raise [Sass::SyntaxError] if the argument list isn't valid SassScript
       def parse_mixin_include_arglist
@@ -83,33 +51,27 @@
           args = arglist || args
           assert_tok(:rparen)
         end
         assert_done
 
-        args.each {|a| a.options = @options}
         args
-      rescue Sass::SyntaxError => e
-        e.modify_backtrace :line => @lexer.line, :filename => @options[:filename]
-        raise e
       end
 
       # Parses the argument list for a mixin definition.
       #
       # @return [Array<Script::Node>] The root nodes of the arguments.
       # @raise [Sass::SyntaxError] if the argument list isn't valid SassScript
       def parse_mixin_definition_arglist
-        args = defn_arglist!(false)
-        assert_done
+        args = []
 
-        args.each do |k, v|
-          k.options = @options
-          v.options = @options if v
+        if try_tok(:lparen)
+          args = defn_arglist(false) || args
+          assert_tok(:rparen)
         end
+        assert_done
+
         args
-      rescue Sass::SyntaxError => e
-        e.modify_backtrace :line => @lexer.line, :filename => @options[:filename]
-        raise e
       end
 
       # Parses a SassScript expression.
       #
       # @overload parse(str, line, offset, filename = nil)
@@ -118,284 +80,143 @@
       # @see Parser#parse
       def self.parse(*args)
         new(*args).parse
       end
 
-      PRECEDENCE = [
-        :comma, :single_eq, :concat, :or, :and,
-        [:eq, :neq],
-        [:gt, :gte, :lt, :lte],
-        [:plus, :minus],
-        [:times, :div, :mod],
-      ]
-
-      ASSOCIATIVE = [:comma, :concat, :plus, :times]
-
       class << self
-        # Returns an integer representing the precedence
-        # of the given operator.
-        # A lower integer indicates a looser binding.
-        #
-        # @private
-        def precedence_of(op)
-          PRECEDENCE.each_with_index do |e, i|
-            return i if Array(e).include?(op)
-          end
-          raise "[BUG] Unknown operator #{op}"
-        end
-
-        # Returns whether or not the given operation is associative.
-        #
-        # @private
-        def associative?(op)
-          ASSOCIATIVE.include?(op)
-        end
-
         private
 
         # Defines a simple left-associative production.
         # name is the name of the production,
         # sub is the name of the production beneath it,
         # and ops is a list of operators for this precedence level
         def production(name, sub, *ops)
           class_eval <<RUBY
             def #{name}
-              interp = try_ops_after_interp(#{ops.inspect}, #{name.inspect}) and return interp
               return unless e = #{sub}
               while tok = try_tok(#{ops.map {|o| o.inspect}.join(', ')})
-                interp = try_op_before_interp(tok, e) and return interp
-                line = @lexer.line
                 e = Operation.new(e, assert_expr(#{sub.inspect}), tok.type)
-                e.line = line
               end
               e
             end
 RUBY
         end
 
         def unary(op, sub)
           class_eval <<RUBY
             def unary_#{op}
-              return #{sub} unless tok = try_tok(:#{op})
-              interp = try_op_before_interp(tok) and return interp
-              line = @lexer.line 
-              op = UnaryOperation.new(assert_expr(:unary_#{op}), :#{op})
-              op.line = line
-              op
+              return #{sub} unless try_tok(:#{op})
+              UnaryOperation.new(assert_expr(:unary_#{op}), :#{op})
             end
 RUBY
         end
       end
 
       private
 
-      # @private
-      def lexer_class; Lexer; end
+      production :expr, :concat, :comma
 
-      production :expr, :interpolation, :comma
-      production :equals, :interpolation, :single_eq
-
-      def try_op_before_interp(op, prev = nil)
-        return unless @lexer.peek && @lexer.peek.type == :begin_interpolation
-        wb = @lexer.whitespace?(op)
-        str = Script::String.new(Lexer::OPERATORS_REVERSE[op.type])
-        str.line = @lexer.line
-        interp = Script::Interpolation.new(prev, str, nil, wb, !:wa, :originally_text)
-        interp.line = @lexer.line
-        interpolation(interp)
-      end
-
-      def try_ops_after_interp(ops, name)
-        return unless @lexer.after_interpolation?
-        return unless op = try_tok(*ops)
-        interp = try_op_before_interp(op) and return interp
-
-        wa = @lexer.whitespace?
-        str = Script::String.new(Lexer::OPERATORS_REVERSE[op.type])
-        str.line = @lexer.line
-        interp = Script::Interpolation.new(nil, str, assert_expr(name), !:wb, wa, :originally_text)
-        interp.line = @lexer.line
-        return interp
-      end
-
-      def interpolation(first = concat)
-        e = first
-        while interp = try_tok(:begin_interpolation)
-          wb = @lexer.whitespace?(interp)
-          line = @lexer.line
-          mid = parse_interpolated
-          wa = @lexer.whitespace?
-          e = Script::Interpolation.new(e, mid, concat, wb, wa)
-          e.line = line
-        end
-        e
-      end
-
       def concat
         return unless e = or_expr
         while sub = or_expr
-          e = node(Operation.new(e, sub, :concat))
+          e = Operation.new(e, sub, :concat)
         end
         e
       end
 
       production :or_expr, :and_expr, :or
       production :and_expr, :eq_or_neq, :and
       production :eq_or_neq, :relational, :eq, :neq
       production :relational, :plus_or_minus, :gt, :gte, :lt, :lte
       production :plus_or_minus, :times_div_or_mod, :plus, :minus
-      production :times_div_or_mod, :unary_plus, :times, :div, :mod
+      production :times_div_or_mod, :unary_minus, :times, :div, :mod
 
-      unary :plus, :unary_minus
       unary :minus, :unary_div
       unary :div, :unary_not # For strings, so /foo/bar works
-      unary :not, :ident
+      unary :not, :funcall
 
-      def ident
-        return funcall unless @lexer.peek && @lexer.peek.type == :ident
-        return if @stop_at && @stop_at.include?(@lexer.peek.value)
-
-        name = @lexer.next
-        if color = Color::HTML4_COLORS[name.value.downcase]
-          return node(Color.new(color))
+      def funcall
+        return paren unless name = try_tok(:ident)
+        # An identifier without arguments is just a string
+        unless try_tok(:lparen)
+          warn(<<END)
+DEPRECATION WARNING:
+On line #{name.line}, character #{name.offset}#{" of '#{@filename}'" if @filename}
+Implicit strings have been deprecated and will be removed in version 3.0.
+'#{name.value}' was not quoted. Please add double quotes (e.g. "#{name.value}").
+END
+          Script::String.new(name.value)
+        else
+          args = arglist || []
+          assert_tok(:rparen)
+          Script::Funcall.new(name.value, args)
         end
-        node(Script::String.new(name.value, :identifier))
       end
 
-      def funcall
-        return raw unless tok = try_tok(:funcall)
-        args = fn_arglist || []
-        assert_tok(:rparen)
-        node(Script::Funcall.new(tok.value, args))
-      end
-
-      def defn_arglist!(must_have_default)
-        return [] unless try_tok(:lparen)
-        return [] if try_tok(:rparen)
-        res = []
-        loop do
-          line = @lexer.line
-          offset = @lexer.offset + 1
-          c = assert_tok(:const)
-          var = Script::Variable.new(c.value)
-          if tok = (try_tok(:colon) || try_tok(:single_eq))
-            val = assert_expr(:concat)
-
-            if tok.type == :single_eq
-              val.context = :equals
-              val.options = @options
-              Script.equals_warning("mixin argument defaults", "$#{c.value}",
-                val.to_sass, false, line, offset, @options[:filename])
-            end
-            must_have_default = true
-          elsif must_have_default
-            raise SyntaxError.new("Required argument #{var.inspect} must come before any optional arguments.")
-          end
-          res << [var, val]
-          break unless try_tok(:comma)
+      def defn_arglist(must_have_default)
+        return unless c = try_tok(:const)
+        var = Script::Variable.new(c.value)
+        if try_tok(:single_eq)
+          val = assert_expr(:concat)
+        elsif must_have_default
+          raise SyntaxError.new("Required argument #{var.inspect} must come before any optional arguments.", @line)
         end
-        assert_tok(:rparen)
-        res
-      end
 
-      def fn_arglist
-        return unless e = equals
-        return [e] unless try_tok(:comma)
-        [e, *assert_expr(:fn_arglist)]
+        return [[var, val]] unless try_tok(:comma)
+        [[var, val], *defn_arglist(val)]
       end
 
       def arglist
-        return unless e = interpolation
+        return unless e = concat
         return [e] unless try_tok(:comma)
-        [e, *assert_expr(:arglist)]
+        [e, *arglist]
       end
 
-      def raw
-        return special_fun unless tok = try_tok(:raw)
-        node(Script::String.new(tok.value))
-      end
-
-      def special_fun
-        return paren unless tok = try_tok(:special_fun)
-        first = node(Script::String.new(tok.value.first))
-        Haml::Util.enum_slice(tok.value[1..-1], 2).inject(first) do |l, (i, r)|
-          Script::Interpolation.new(
-            l, i, r && node(Script::String.new(r)),
-            false, false)
-        end
-      end
-
       def paren
         return variable unless try_tok(:lparen)
-        was_in_parens = @in_parens
-        @in_parens = true
         e = assert_expr(:expr)
         assert_tok(:rparen)
         return e
-      ensure
-        @in_parens = was_in_parens
       end
 
       def variable
         return string unless c = try_tok(:const)
-        node(Variable.new(*c.value))
+        Variable.new(c.value)
       end
 
       def string
-        return number unless first = try_tok(:string)
+        return literal unless first = try_tok(:string)
         return first.value unless try_tok(:begin_interpolation)
-        line = @lexer.line
         mid = parse_interpolated
         last = assert_expr(:string)
-        interp = StringInterpolation.new(first.value, mid, last)
-        interp.line = line
-        interp
+        Operation.new(first.value, Operation.new(mid, last, :plus), :plus)
       end
 
-      def number
-        return literal unless tok = try_tok(:number)
-        num = tok.value
-        num.original = num.to_s unless @in_parens
-        num
-      end
-
       def literal
-        (t = try_tok(:color, :bool)) && (return t.value)
+        (t = try_tok(:number, :color, :bool)) && (return t.value)
       end
 
       # It would be possible to have unified #assert and #try methods,
       # but detecting the method/token difference turns out to be quite expensive.
 
-      EXPR_NAMES = {
-        :string => "string",
-        :default => "expression (e.g. 1px, bold)",
-        :arglist => "mixin argument",
-        :fn_arglist => "function argument",
-      }
-
       def assert_expr(name)
         (e = send(name)) && (return e)
-        @lexer.expected!(EXPR_NAMES[name] || EXPR_NAMES[:default])
+        raise Sass::SyntaxError.new("Expected expression, was #{@lexer.done? ? 'end of text' : "#{@lexer.peek.type} token"}.")
       end
 
       def assert_tok(*names)
         (t = try_tok(*names)) && (return t)
-        @lexer.expected!(names.map {|tok| Lexer::TOKEN_NAMES[tok] || tok}.join(" or "))
+        raise Sass::SyntaxError.new("Expected #{names.join(' or ')} token, was #{@lexer.done? ? 'end of text' : "#{@lexer.peek.type} token"}.")
       end
 
       def try_tok(*names)
         peeked =  @lexer.peek
         peeked && names.include?(peeked.type) && @lexer.next
       end
 
       def assert_done
         return if @lexer.done?
-        @lexer.expected!(EXPR_NAMES[:default])
-      end
-
-      def node(node)
-        node.line = @lexer.line
-        node
+        raise Sass::SyntaxError.new("Unexpected #{@lexer.peek.type} token.")
       end
     end
   end
 end