Class: Gherkin::TokenScanner

Inherits:
Object
  • Object
show all
Defined in:
lib/gherkin/token_scanner.rb

Overview

The scanner reads a gherkin doc (typically read from a .feature file) and creates a token for line. The tokens are passed to the parser, which outputs an AST (Abstract Syntax Tree).

If the scanner sees a # language header, it will reconfigure itself dynamically to look for Gherkin keywords for the associated language. The keywords are defined in gherkin-languages.json.

Instance Method Summary collapse

Constructor Details

#initialize(source_or_io) ⇒ TokenScanner

Returns a new instance of TokenScanner.



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# File 'lib/gherkin/token_scanner.rb', line 14

def initialize(source_or_io)
  @line_number = 0

  case(source_or_io)
  when String
    @io = StringIO.new(source_or_io)
  when StringIO, IO
    @io = source_or_io
  else
    fail ArgumentError, "Please a pass String, StringIO or IO. I got a #{source_or_io.class}"
  end
end

Instance Method Details

#read ⇒ Object 



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# File 'lib/gherkin/token_scanner.rb', line 27

def read
  location = {line: @line_number += 1, column: 0}
  if @io.nil? || line = @io.gets
    gherkin_line = line ? GherkinLine.new(line, location[:line]) : nil
    Token.new(gherkin_line, location)
  else
    @io.close unless @io.closed? # ARGF closes the last file after final gets
    @io = nil
    Token.new(nil, location)
  end
end