result_with_hash

0_result_with_hash.rb

require "erb"

erb_obj = ERB.new("<%=name%> \"Hello <%=first_name%> <%=last_name%>!\"")

name = 'honoka'
last_name = 'kousaka'

puts erb_obj.result_with_hash(first_name: 'kotori', last_name: 'minami')
puts "Top level name is #{name}, #{last_name}" 

user = {first_name: 'umi', last_name: 'sonoda'}
puts erb_obj.result_with_hash(user)
puts "Top level name is #{name}, #{last_name}" 

expected

honoka "Hello kotori minami!"
Top level name is honoka, kousaka
honoka "Hello umi sonoda!"
Top level name is honoka, kousaka

fixed

  def result_with_hash(hash)
    b = new_toplevel
    
    backup = {}
    news = []
    hash.each_pair do |key, value|
        if b.local_variable_defined?(key)
          backup[key] = b.local_variable_get(key)
        else
          news << key
        end
        b.local_variable_set(key, value)
    end

    ret = result(b)

    backup.each_pair do |key, value|
      b.local_variable_set(key, value)
    end
    news.each { |key| b.local_variable_set(key, nil) }

    ret
  end

get

honoka "Hello kotori minami!"
Top level name is honoka, minami # we want to honoka kousaka
honoka "Hello umi sonoda!"
Top level name is honoka, sonoda # we want to honoka kousaka