def populate_extends(extends, extendee, extend_node = nil, parent_directives = [])
extendee.members.each do |seq|
if seq.members.size > 1
raise Sass::SyntaxError.new("Can't extend #{seq}: can't extend nested selectors")
end
sseq = seq.members.first
if !sseq.is_a?(Sass::Selector::SimpleSequence)
raise Sass::SyntaxError.new("Can't extend #{seq}: invalid selector")
elsif sseq.members.any? {|ss| ss.is_a?(Sass::Selector::Parent)}
raise Sass::SyntaxError.new("Can't extend #{seq}: can't extend parent selectors")
end
sel = sseq.members
members.each do |member|
unless member.members.last.is_a?(Sass::Selector::SimpleSequence)
raise Sass::SyntaxError.new("#{member} can't extend: invalid selector")
end
extends[sel] = Sass::Tree::Visitors::Cssize::Extend.new(
member, sel, extend_node, parent_directives, :not_found)
end
end
end