Class: Dommy::TextDecoder

Inherits:
Object
  • Object
show all
Includes:
Bridge::Methods
Defined in:
lib/dommy/text_codec.rb

Overview

‘TextDecoder` — decodes bytes into a String. Supports utf-8, utf-16, utf-16le, utf-16be, iso-8859-1 (best-effort).

Spec: encoding.spec.whatwg.org/#textdecoder

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Bridge::Methods

included

Constructor Details

#initialize(label = "utf-8", options = nil) ⇒ TextDecoder

Returns a new instance of TextDecoder.



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# File 'lib/dommy/text_codec.rb', line 40

def initialize(label = "utf-8", options = nil)
  label = "utf-8" if label.nil? || label.equal?(Bridge::UNDEFINED)
  @encoding = normalize_encoding(label.to_s)
  opts = options.is_a?(Hash) ? options : {}
  @fatal = truthy?(opts["fatal"] || opts[:fatal])
  @ignore_bom = truthy?(opts["ignoreBOM"] || opts[:ignoreBOM])
end

Instance Attribute Details

#encoding ⇒ Object (readonly)

Returns the value of attribute encoding.



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# File 'lib/dommy/text_codec.rb', line 48

def encoding
  @encoding
end

Instance Method Details

#__js_call__(method, args) ⇒ Object 



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# File 'lib/dommy/text_codec.rb', line 84

def __js_call__(method, args)
  case method
  when "decode"
    decode(args[0], args[1])
  end
end

#__js_get__(key) ⇒ Object 



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# File 'lib/dommy/text_codec.rb', line 74

def __js_get__(key)
  case key
  when "encoding" then @encoding
  when "fatal" then @fatal
  when "ignoreBOM" then @ignore_bom
  end
end

#decode(input = nil, options = nil) ⇒ Object

decode(bytes, stream) → String. Accepts a Bytes buffer (JS ArrayBuffer / TypedArray), an Array<Integer>, or a binary String. With ‘fatal: true` an invalid sequence throws a TypeError; otherwise it is replaced with U+FFFD. A leading BOM is stripped unless `ignoreBOM` was set.



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# File 'lib/dommy/text_codec.rb', line 57

def decode(input = nil, options = nil)
  stream = options.is_a?(Hash) && truthy?(options["stream"] || options[:stream])
  bytes = extract_bytes(input)

  if @encoding == "utf-8"
    decode_utf8(bytes, stream)
  else
    # Non-UTF-8 (utf-16le/be, iso-8859-1): no streaming/exact-FFFD semantics,
    # best-effort via Ruby's transcoder.
    bytes = strip_bom(bytes) unless @ignore_bom
    raw = bytes.force_encoding(ruby_encoding)
    raise Bridge::TypeError, "decode failed" if @fatal && !raw.valid_encoding?

    raw.encode(Encoding::UTF_8, invalid: :replace, undef: :replace)
  end
end

#fatal? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/dommy/text_codec.rb', line 50

def fatal? = @fatal

#ignore_bom? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/dommy/text_codec.rb', line 51

def ignore_bom? = @ignore_bom