I ran into some issues using `plsm` library with Phoenix 1.4.10 and El;ixir 1.9. This script remedied most of them.

post_plsm.rb

# frozen_string_literal: true

require 'active_support/inflector'

module PatchedString
  refine String do
    def camelcase
      split('_').map(&:capitalize).join
    end
  end
end

# post processor for plsm tool
class PostPlsm
  def self.run(dirname)
    Dir.glob("./lib/#{dirname}/*s.ex") do |f|
      process(f)
    end
  end

  using PatchedString

  def self.fix_module(match)
    "#{match[1]}defmodule #{match[2].singularize} do"
  end

  def self.fix_field(match)
    "#{match[1]}field #{match[2]}, :string#{match[3]}"
  end

  def self.fix_cast(match)
    "#{match[1]}#{match[2]}"
  end

  def self.process(filename)
    path = "#{filename.gsub(/\.ex$/, '').singularize}.ex"
    File.open(path,'w') do |file|
      File.readlines(filename).each do |line|
        if line =~ /\A(\s*)defmodule\s+(.+)\s+do\s*\Z/
          file.puts fix_module(Regexp.last_match)
        elsif line =~ /\A(\s*)field\s+:id,\s+:integer\s*\Z/
          next
        elsif line =~ /\A(\s*)field\s+(:\w+),\s+:text(.*)\Z/
          file.puts fix_field(Regexp.last_match)
        elsif line =~ /\A(.*\|> cast\(params,\s*\[):id,\s*(.*\)).*\Z/
          file.puts fix_cast(Regexp.last_match)
        else
          file.puts line
        end
      end
    end
  end
end

if $PROGRAM_NAME == __FILE__
  raise ArgumentException, 'module name required' unless ARGV.size >= 1

  PostPlsm.run(ARGV[0])
end