Module: RubyNext::Language

Defined in:
lib/ruby-next/language.rb,
lib/ruby-next/language/eval.rb,
lib/ruby-next/language/setup.rb,
lib/ruby-next/language/parser.rb,
lib/ruby-next/language/runtime.rb,
lib/ruby-next/language/rewriters/base.rb,
lib/ruby-next/language/rewriters/2.4/dir.rb,
lib/ruby-next/language/rewriters/3.0/in_pattern.rb,
lib/ruby-next/language/rewriters/2.7/args_forward.rb,
lib/ruby-next/language/rewriters/3.0/find_pattern.rb,
lib/ruby-next/language/rewriters/2.6/endless_range.rb,
lib/ruby-next/language/rewriters/3.0/endless_method.rb,
lib/ruby-next/language/rewriters/3.1/shorthand_hash.rb,
lib/ruby-next/language/rewriters/2.1/required_kwargs.rb,
lib/ruby-next/language/rewriters/2.3/safe_navigation.rb,
lib/ruby-next/language/rewriters/2.7/numbered_params.rb,
lib/ruby-next/language/rewriters/3.1/anonymous_block.rb,
lib/ruby-next/language/rewriters/2.1/numeric_literals.rb,
lib/ruby-next/language/rewriters/2.3/squiggly_heredoc.rb,
lib/ruby-next/language/rewriters/2.7/pattern_matching.rb,
lib/ruby-next/language/rewriters/3.1/pin_vars_pattern.rb,
lib/ruby-next/language/rewriters/2.5/rescue_within_block.rb,
lib/ruby-next/language/rewriters/3.0/args_forward_leading.rb,
lib/ruby-next/language/rewriters/proposed/method_reference.rb,
lib/ruby-next/language/rewriters/3.1/endless_method_command.rb,
lib/ruby-next/language/rewriters/proposed/bind_vars_pattern.rb,
lib/ruby-next/language/rewriters/3.1/refinement_import_methods.rb,
lib/ruby-next/language/rewriters/3.1/oneline_pattern_parensless.rb

Overview

Language module contains tools to transpile newer Ruby syntax into an older one.

It works the following way:

- Takes a Ruby source code as input
- Generates the AST using the edge parser (via the `parser` gem)
- Pass this AST through the list of processors (one feature = one processor)
- Each processor may modify the AST
- Generates a transpiled source code from the transformed AST (via the `unparser` gem)

Defined Under Namespace

Modules: BuilderExt, ClassEval, Eval, GemTranspiler, InstanceEval, KernelEval, Rewriters, Runtime Classes: Builder, TransformContext

Constant Summary collapse

RewriterNotFoundError = 
Class.new(StandardError)
MODES = 
%i[rewrite ast].freeze

Class Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Class Attribute Details

.mode ⇒ Object

Returns the value of attribute mode.



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# File 'lib/ruby-next/language.rb', line 72

def mode
  @mode
end

.rewriters ⇒ Object

Returns the value of attribute rewriters.



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# File 'lib/ruby-next/language.rb', line 65

def rewriters
  @rewriters
end

.strategy ⇒ Object

Returns the value of attribute strategy.



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# File 'lib/ruby-next/language.rb', line 68

def strategy
  @strategy
end

.watch_dirs ⇒ Object

Returns the value of attribute watch_dirs.



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# File 'lib/ruby-next/language.rb', line 66

def watch_dirs
  @watch_dirs
end

Class Method Details

.ast? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/ruby-next/language.rb', line 83

def ast?
  mode == :ast
end

.current_rewriters ⇒ Object

Rewriters required for the current version



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# File 'lib/ruby-next/language.rb', line 127

def current_rewriters
  @current_rewriters ||= rewriters.select(&:unsupported_syntax?)
end

.parse(source, file = "(string)") ⇒ Object 



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# File 'lib/ruby-next/language/parser.rb', line 36

def parse(source, file = "(string)")
  buffer = ::Parser::Source::Buffer.new(file).tap do |buffer|
    buffer.source = source
  end

  parser.parse(buffer)
rescue ::Parser::SyntaxError => e
  raise ::SyntaxError, e.message
end

.parse_with_comments(source, file = "(string)") ⇒ Object 



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# File 'lib/ruby-next/language/parser.rb', line 46

def parse_with_comments(source, file = "(string)")
  buffer = ::Parser::Source::Buffer.new(file).tap do |buffer|
    buffer.source = source
  end

  parser.parse_with_comments(buffer)
rescue ::Parser::SyntaxError => e
  raise ::SyntaxError, e.message
end

.parser ⇒ Object 



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# File 'lib/ruby-next/language/parser.rb', line 28

def parser
  ::Parser::RubyNext.new(Builder.new).tap do |prs|
    prs.diagnostics.tap do |diagnostics|
      diagnostics.all_errors_are_fatal = true
    end
  end
end

.rewrite? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/ruby-next/language.rb', line 79

def rewrite?
  mode == :rewrite?
end

.runtime! ⇒ Object 



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# File 'lib/ruby-next/language.rb', line 87

def runtime!
  require "ruby-next/language/rewriters/runtime"

  @runtime = true
end

.runtime? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/ruby-next/language.rb', line 93

def runtime?
  @runtime
end

.select_rewriters(*names) ⇒ Object

This method guarantees that rewriters will be returned in order they defined in Language module



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# File 'lib/ruby-next/language.rb', line 132

def select_rewriters(*names)
  rewriters_delta = names - rewriters.map { |rewriter| rewriter::NAME }
  if rewriters_delta.any?
    raise RewriterNotFoundError, "Rewriters not found: #{rewriters_delta.join(",")}"
  end

  rewriters.select { |rewriter| names.include?(rewriter::NAME) }
end

.setup_gem_load_path(lib_dir = "lib", rbnext_dir: RUBY_NEXT_DIR, transpile: false) ⇒ Object 



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# File 'lib/ruby-next/language/setup.rb', line 31

def setup_gem_load_path(lib_dir = "lib", rbnext_dir: RUBY_NEXT_DIR, transpile: false)
  called_from = caller_locations(1, 1).first.path
  dirname = File.realpath(File.dirname(called_from))

  loop do
    basename = File.basename(dirname)
    raise "Couldn't find gem's load dir: #{lib_dir}" if basename == dirname

    break if basename == lib_dir

    dirname = File.dirname(basename)
  end

  dirname = File.realpath(dirname)

  return if Language.runtime? && Language.watch_dirs.include?(dirname)

  next_dirname = File.join(dirname, rbnext_dir)

  GemTranspiler.maybe_transpile(File.dirname(dirname), lib_dir, next_dirname) if transpile

  current_index = $LOAD_PATH.find_index do |load_path|
    pn = Pathname.new(load_path)
    pn.exist? && pn.realpath.to_s == dirname
  end

  raise "Gem's lib is not in the $LOAD_PATH: #{dirname}" if current_index.nil?

  version = RubyNext.next_ruby_version

  loop do
    break unless version

    version_dir = File.join(next_dirname, version.segments[0..1].join("."))

    if File.exist?(version_dir)
      $LOAD_PATH.insert current_index, version_dir
      current_index += 1
    end

    version = RubyNext.next_ruby_version(version)
  end
end

.transform(source, rewriters: self.rewriters, using: RubyNext::Core.refine?, context: TransformContext.new) ⇒ Object 



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# File 'lib/ruby-next/language.rb', line 97

def transform(source, rewriters: self.rewriters, using: RubyNext::Core.refine?, context: TransformContext.new)
  retried = 0
  new_source = nil
  begin
    new_source =
      if mode == :rewrite
        rewrite(source, rewriters: rewriters, using: using, context: context)
      else
        regenerate(source, rewriters: rewriters, using: using, context: context)
      end
  rescue Unparser::UnknownNodeError => err
    RubyNext.warn "Ruby Next fallbacks to \"rewrite\" transpiling mode since the version of Unparser you use doesn't support some syntax yet: #{err.message}.\n" \
      "Try upgrading the Unparser or set transpiling mode to \"rewrite\" in case you use some edge or experimental syntax."
    self.mode = :rewrite
    retried += 1
    retry unless retried > 1
    raise
  end

  return new_source unless RubyNext::Core.refine?
  return new_source unless using && context.use_ruby_next?

  Core.inject! new_source.dup
end

.transformable?(path) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/ruby-next/language.rb', line 122

def transformable?(path)
  watch_dirs.any? { |dir| path.start_with?(dir) }
end

Instance Method Details

#runtime? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/ruby-next/language/setup.rb', line 26

def runtime?
  false
end