module Ruby2JS

Kinda like Object.assign, except it handles properties

Note: Object.defineProperties, Object.getOwnPropertyNames, etc. technically

were not part of ES5, but were implemented by IE prior to ES6, and are
the only way to implement getters and setters.

Manage a list of methods to be included or excluded. This allows fine grained control over filters.

Note care is taken to run all the filters first before camelCasing. This ensures that Ruby methods like each_pair can be mapped to JavaScript before camelcasing.

Jquery functions are either invoked using jQuery() or, more commonly, $(). The former presents no problem, the latter is not legal Ruby.

Accordingly, the first accomodation this filter provides is to map $$ to $. This works find for $$.ajax and the like, but less so for direct calls as $$(this) is also a syntax error. $$.(this) and $$[this] will work but are a bit clumsy.

So as a second accomodation, the rarely used binary one’s complement unary operator (namely, ~) is usurped, and the AST is rewritten to provide the effect of this operator being of a higher precedence than method calls. Passing multiple parameters can be accomplished by using array index syntax (e.g., ~[‘a’, self])

As a part of this rewriting, calls to getters and setters are rewritten to match jQuery’s convention for getters and setters:

http://learn.jquery.com/using-jquery-core/working-with-selections/

Selected DOM properties (namely checked, disabled, readOnly, and required) can also use getter and setter syntax. Additionally, readOnly may be spelled ‘readonly’.

Of course, using jQuery’s style of getter and setter calls is supported, and indeed is convenient when using method chaining.

Additionally, the tilde AST rewriting can be avoided by using consecutive tildes (~~ is a common Ruby idiom for Math.floor, ~~~ will return the binary one’s complement.); and the getter and setter AST rewriting can be avoided by the use of parenthesis, e.g. (~this).text.

Finally, the fourth parameter of $.post defaults to :json, allowing Ruby block syntax to be used for the success function.

Some examples of before/after conversions:

 ~this.val
 $(this).val()

 ~"button.continue".html = "Next Step..."
 $("button.continue").html("Next Step...")

 ~"button".readonly = false
 $("button").prop("readOnly", false)

$$.ajax(
  url: "/api/getWeather",
  data: {zipcode: 97201},
  success: proc do |data|
    `"#weather-temp".html = "<strong>#{data}</strong> degrees"
  end
)

$.ajax({
  url: "/api/getWeather",
  data: {zipcode: 97201},
  success: function(data) {
    $("#weather-temp").html("<strong>" + data + "</strong> degrees");
  }
})

Convert Wunderbar syntax to JSX

Experimental secure random support

TODO: This feature is deprecated.

convert a JSX expression into wunderbar statements

Once the syntax is converted to pure Ruby statements, it can then be converted into either React or Vue rendering instructions.

Instances of this class keep track of both classes and modules that we have seen before, as well as the methods and properties that are defined in each.

Use cases this enables:

* detection of "open" classes and modules, i.e., redefining a class or
  module that was previously declared in order to add or modify methods
  or properties.

* knowing when to prefix method or property access with `this.` and
  when to add `.bind(this)` for methods and properties that were defined
  outside of this class.

Public Class Methods

compile(source, options={}) click to toggle source
# File lib/ruby2js/execjs.rb, line 7
def self.compile(source, options={})
  ExecJS.compile(convert(source, options).to_s)
end
convert(source, options={}) click to toggle source

TODO: this method has gotten long and unwieldy!

# File lib/ruby2js.rb, line 219
def self.convert(source, options={})
  Filter.autoregister unless RUBY_ENGINE == 'opal'
  options = options.dup

  if Proc === source
    file,line = source.source_location
    source = IO.read(file)
    ast, comments = parse(source)
    comments = Parser::Source::Comment.associate(ast, comments) if ast
    ast = find_block( ast, line )
    options[:file] ||= file
  elsif Parser::AST::Node === source
    ast, comments = source, {}
    source = ast.loc.expression.source_buffer.source
  else
    ast, comments = parse( source, options[:file] )
    comments = ast ? Parser::Source::Comment.associate(ast, comments) : {}
  end

  # check if magic comment is present
  first_comment = comments.values.first&.map(&:text)&.first
  if first_comment
    if first_comment.include?(" ruby2js: preset")
      options[:preset] = true
      if first_comment.include?("filters: ")
        options[:filters] = first_comment.match(%r(filters:\s*?([^\s]+)\s?.*$))[1].split(",").map(&:to_sym)
      end
      if first_comment.include?("eslevel: ")
        options[:eslevel] = first_comment.match(%r(eslevel:\s*?([^\s]+)\s?.*$))[1].to_i
      end
      if first_comment.include?("disable_filters: ")
        options[:disable_filters] = first_comment.match(%r(disable_filters:\s*?([^\s]+)\s?.*$))[1].split(",").map(&:to_sym)
      end
    end
    disable_autoimports = first_comment.include?(" autoimports: false")
    disable_autoexports = first_comment.include?(" autoexports: false")
  end

  unless RUBY_ENGINE == 'opal'
    unless options.key?(:config_file) || !File.exist?("config/ruby2js.rb")
      options[:config_file] ||= "config/ruby2js.rb"
    end

    if options[:config_file]
      options = ConfigurationDSL.load_from_file(options[:config_file], options).to_h
    end
  end

  if options[:preset]
    options[:eslevel] ||= @@eslevel_preset_default
    options[:filters] = Filter::PRESET_FILTERS + Array(options[:filters]).uniq
    if options[:disable_filters]
      options[:filters] -= options[:disable_filters]
    end
    options[:comparison] ||= :identity
    options[:underscored_private] = true unless options[:underscored_private] == false
  end
  options[:eslevel] ||= @@eslevel_default
  options[:strict] = @@strict_default if options[:strict] == nil
  options[:module] ||= @@module_default || :esm

  namespace = Namespace.new

  filters = Filter.require_filters(options[:filters] || Filter::DEFAULTS)

  unless filters.empty?
    filter_options = options.merge({ filters: filters })
    filters.dup.each do |filter|
      filters = filter.reorder(filters) if filter.respond_to? :reorder
    end

    filter = Filter::Processor
    filters.reverse.each do |mod|
      filter = Class.new(filter) {include mod} 
    end
    filter = filter.new(comments)

    filter.disable_autoimports = disable_autoimports
    filter.disable_autoexports = disable_autoexports
    filter.options = filter_options
    filter.namespace = namespace
    ast = filter.process(ast)

    unless filter.prepend_list.empty?
      prepend = filter.prepend_list.sort_by {|ast| ast.type == :import ? 0 : 1}
      prepend.reject! {|ast| ast.type == :import} if filter.disable_autoimports
      ast = Parser::AST::Node.new(:begin, [*prepend, ast])
    end
  end

  ruby2js = Ruby2JS::Converter.new(ast, comments)

  ruby2js.binding = options[:binding]
  ruby2js.ivars = options[:ivars]
  ruby2js.eslevel = options[:eslevel]
  ruby2js.strict = options[:strict]
  ruby2js.comparison = options[:comparison] || :equality
  ruby2js.or = options[:or] || :logical
  ruby2js.module_type = options[:module] || :esm
  ruby2js.underscored_private = (options[:eslevel] < 2022) || options[:underscored_private]

  ruby2js.namespace = namespace

  if ruby2js.binding and not ruby2js.ivars
    ruby2js.ivars = ruby2js.binding.eval \
      'Hash[instance_variables.map {|var| [var, instance_variable_get(var)]}]'
  elsif options[:scope] and not ruby2js.ivars
    scope = options.delete(:scope)
    ruby2js.ivars = Hash[scope.instance_variables.map {|var|
      [var, scope.instance_variable_get(var)]}]
  end

  ruby2js.width = options[:width] if options[:width]

  ruby2js.enable_vertical_whitespace if source.include? "\n"

  ruby2js.convert

  ruby2js.timestamp options[:file]

  ruby2js.file_name = options[:file] || ast&.loc&.expression&.source_buffer&.name || ''

  ruby2js
end
eslevel_default() click to toggle source
# File lib/ruby2js.rb, line 30
def self.eslevel_default
  @@eslevel_default
end
eslevel_default=(level) click to toggle source
# File lib/ruby2js.rb, line 34
def self.eslevel_default=(level)
  @@eslevel_default = level
end
eval(source, options={}) click to toggle source
# File lib/ruby2js/execjs.rb, line 11
def self.eval(source, options={})
  ExecJS.eval(convert(source, options.merge(strict: false)).to_s)
end
exec(source, options={}) click to toggle source
# File lib/ruby2js/execjs.rb, line 15
def self.exec(source, options={})
  ExecJS.exec(convert(source, options).to_s)
end
find_block(ast, line) click to toggle source
# File lib/ruby2js.rb, line 360
def self.find_block(ast, line)
  if ast.type == :block and ast.loc.expression.line == line
    return ast.children.last
  end

  ast.children.each do |child|
    if Parser::AST::Node === child
      block = find_block child, line
      return block if block
    end
  end

  nil
end
jsx2_rb(string) click to toggle source
# File lib/ruby2js/jsx.rb, line 10
def self.jsx2_rb(string)
  JsxParser.new(string.chars.each).parse.join("\n")
end
module_default() click to toggle source
# File lib/ruby2js.rb, line 46
def self.module_default
  @@module_default
end
module_default=(module_type) click to toggle source
# File lib/ruby2js.rb, line 50
def self.module_default=(module_type)
  @@module_default = module_type
end
parse(source, file=nil, line=1) click to toggle source
# File lib/ruby2js.rb, line 344
def self.parse(source, file=nil, line=1)
  buffer = Parser::Source::Buffer.new(file, line)
  buffer.source = source.encode('UTF-8')
  parser = Parser::CurrentRuby.new
  parser.diagnostics.all_errors_are_fatal = true
  parser.diagnostics.consumer = lambda {|diagnostic| nil}
  parser.builder.emit_file_line_as_literals = false
  parser.parse_with_comments(buffer)
rescue Parser::SyntaxError => e
  split = source[0..e.diagnostic.location.begin_pos].split("\n")
  line, col = split.length, split.last.length
  message = "line #{line}, column #{col}: #{e.diagnostic.message}"
  message += "\n in file #{file}" if file
  raise Ruby2JS::SyntaxError.new(message, e.diagnostic)
end
strict_default() click to toggle source
# File lib/ruby2js.rb, line 38
def self.strict_default
  @@strict_default
end
strict_default=(level) click to toggle source
# File lib/ruby2js.rb, line 42
def self.strict_default=(level)
  @@strict_default = level
end