require 'test/unit'

class TestSyntax < Test::Unit::TestCase
  def valid_syntax?(code, fname)
    code = code.dup.force_encoding("ascii-8bit")
    code.sub!(/\A(?:\xef\xbb\xbf)?(\s*\#.*$)*(\n)?/n) {
      "#$&#{"\n" if $1 && !$2}BEGIN{throw tag, :ok}\n"
    }
    code.force_encoding("us-ascii")
    catch {|tag| eval(code, binding, fname, 0)}
  rescue SyntaxError
    false
  end

  def test_syntax
    assert_nothing_raised(Exception) do
      for script in Dir[File.expand_path("../../../{lib,sample,ext,test}/**/*.rb", __FILE__)].sort
        assert(valid_syntax?(IO::read(script), script))
      end
    end
  end

  def test_must_ascii_compatible
    require 'tempfile'
    f = Tempfile.new("must_ac_")
    Encoding.list.each do |enc|
      next unless enc.ascii_compatible?
      make_tmpsrc(f, "# -*- coding: #{enc.name} -*-")
      assert_nothing_raised(ArgumentError, enc.name) {load(f.path)}
    end
    Encoding.list.each do |enc|
      next if enc.ascii_compatible?
      make_tmpsrc(f, "# -*- coding: #{enc.name} -*-")
      assert_raise(ArgumentError, enc.name) {load(f.path)}
    end
    f.close!
  end

  def test_script_lines
    require 'tempfile'
    f = Tempfile.new("bug4361_")
    bug4361 = '[ruby-dev:43168]'
    with_script_lines do |debug_lines|
      Encoding.list.each do |enc|
        next unless enc.ascii_compatible?
        make_tmpsrc(f, "# -*- coding: #{enc.name} -*-\n#----------------")
        load(f.path)
        assert_equal([f.path], debug_lines.keys)
        assert_equal([enc, enc], debug_lines[f.path].map(&:encoding), bug4361)
      end
    end
    f.close!
  end

  private

  def make_tmpsrc(f, src)
    f.open
    f.truncate(0)
    f.puts(src)
    f.close
  end

  def with_script_lines
    script_lines = nil
    debug_lines = {}
    Object.class_eval do
      if defined?(SCRIPT_LINES__)
        script_lines = SCRIPT_LINES__
        remove_const :SCRIPT_LINES__
      end
      const_set(:SCRIPT_LINES__, debug_lines)
    end
    yield debug_lines
  ensure
    Object.class_eval do
      remove_const :SCRIPT_LINES__
      const_set(:SCRIPT_LINES__, script_lines) if script_lines
    end
  end
end