Module: Hashstructor::InstanceMethods

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# File 'lib/hashstructor/instance_methods.rb', line 20

def hashstruct(hash)
  raise HashstructorError, "hashstruct expects a hash." unless hash.is_a?(Hash)

  members = self.class.hashstructor_members

  # This could be done inline, but I'd rather loop twice and get this check
  # out of the way ahead of time because of the perf hit when dealing with
  # deeply nested structures.
  partitioned_members = members.partition { |m| hash[m.name] || hash[m.name.to_s] }

  existing_members = partitioned_members[0]
  missing_members = partitioned_members[1]
  raise HashstructorError, "Missing required members: #{missing_members.map { |m| m.name }.join(", ")}" \
    if missing_members.any? { |m| m.required }

  existing_members.each do |member|
    raw_value = hash[member.name] || hash[member.name.to_s]
    out_value = nil

    case member.member_type
    when :normal
      raise HashstructorError, "member '#{member.name}' expects a single value, got #{raw_value.class.name}." \
        if member.options[:no_collections] && raw_value.is_a?(Enumerable)

      out_value = member.parse_single(raw_value)

    when :hash
      raise HashstructorError, "member '#{member.name}' expects a Hash, got #{raw_value.class.name}." \
        unless raw_value.is_a?(Hash)

      out_value = {}
      raw_value.each_pair do |k, v|
        key = member.options[:string_keys] ? k.to_s : k.to_s.to_sym

        out_value[key] = member.parse_single(v)
      end

    when :array, :set
      raise HashstructorError, "member '#{member.name}' expects an Enumerable, got #{raw_value.class.name}"\
        unless raw_value.is_a?(Enumerable)

      out_value = raw_value.map { |v| member.parse_single(v) }

      out_value = out_value.to_set if member.member_type == :set
    end

    instance_variable_set("@#{member.name}", out_value)
  end
end