Class: Gem::StreamUI

Inherits:
Object
  • Object
show all
Defined in:
lib/rubygems/user_interaction.rb

Overview

Gem::StreamUI implements a simple stream based user interface.

Direct Known Subclasses

ConsoleUI, SilentUI

Defined Under Namespace

Classes: SilentDownloadReporter, SilentProgressReporter, SimpleProgressReporter, ThreadedDownloadReporter, VerboseProgressReporter

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(in_stream, out_stream, err_stream = $stderr, usetty = true) ⇒ StreamUI

Creates a new StreamUI wrapping in_stream for user input, out_stream for standard output, err_stream for error output. If usetty is true then special operations (like asking for passwords) will use the TTY commands to disable character echo.



193
194
195
196
197
198
 
# File 'lib/rubygems/user_interaction.rb', line 193

def initialize(in_stream, out_stream, err_stream = $stderr, usetty = true)
  @ins = in_stream
  @outs = out_stream
  @errs = err_stream
  @usetty = usetty
end

Instance Attribute Details

#errs ⇒ Object (readonly)

The error stream



185
186
187
 
# File 'lib/rubygems/user_interaction.rb', line 185

def errs
  @errs
end

#ins ⇒ Object (readonly)

The input stream



175
176
177
 
# File 'lib/rubygems/user_interaction.rb', line 175

def ins
  @ins
end

#outs ⇒ Object (readonly)

The output stream



180
181
182
 
# File 'lib/rubygems/user_interaction.rb', line 180

def outs
  @outs
end

Instance Method Details

#_gets_noecho ⇒ Object 



317
318
319
320
 
# File 'lib/rubygems/user_interaction.rb', line 317

def _gets_noecho
  require_io_console
  @ins.noecho { @ins.gets }
end

#alert(statement, question = nil) ⇒ Object

Display an informational alert. Will ask question if it is not nil.



332
333
334
335
 
# File 'lib/rubygems/user_interaction.rb', line 332

def alert(statement, question = nil)
  @outs.puts "INFO:  #{statement}"
  ask(question) if question
end

#alert_error(statement, question = nil) ⇒ Object

Display an error message in a location expected to get error messages. Will ask question if it is not nil.



349
350
351
352
 
# File 'lib/rubygems/user_interaction.rb', line 349

def alert_error(statement, question = nil)
  @errs.puts "ERROR:  #{statement}"
  ask(question) if question
end

#alert_warning(statement, question = nil) ⇒ Object

Display a warning on stderr. Will ask question if it is not nil.



340
341
342
343
 
# File 'lib/rubygems/user_interaction.rb', line 340

def alert_warning(statement, question = nil)
  @errs.puts "WARNING:  #{statement}"
  ask(question) if question
end

#ask(question) ⇒ Object

Ask a question. Returns an answer if connected to a tty, nil otherwise.



281
282
283
284
285
286
287
288
289
290
 
# File 'lib/rubygems/user_interaction.rb', line 281

def ask(question)
  return nil unless tty?

  @outs.print(question + "  ")
  @outs.flush

  result = @ins.gets
  result&.chomp!
  result
end

#ask_for_password(question) ⇒ Object

Ask for a password. Does not echo response to terminal.



295
296
297
298
299
300
301
302
303
304
305
 
# File 'lib/rubygems/user_interaction.rb', line 295

def ask_for_password(question)
  return nil unless tty?

  @outs.print(question, "  ")
  @outs.flush

  password = _gets_noecho
  @outs.puts
  password&.chomp!
  password
end

#ask_yes_no(question, default = nil) ⇒ Object

Ask a question. Returns a true for yes, false for no. If not connected to a tty, raises an exception if default is nil, otherwise returns default.



246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
 
# File 'lib/rubygems/user_interaction.rb', line 246

def ask_yes_no(question, default = nil)
  unless tty?
    if default.nil?
      raise Gem::OperationNotSupportedError,
            "Not connected to a tty and no default specified"
    else
      return default
    end
  end

  default_answer = case default
                   when nil
                     "yn"
                   when true
                     "Yn"
                   else
                     "yN"
  end

  result = nil

  while result.nil? do
    result = case ask "#{question} [#{default_answer}]"
             when /^y/i then true
             when /^n/i then false
             when /^$/  then default
    end
  end

  result
end

#backtrace(exception) ⇒ Object

Prints a formatted backtrace to the errors stream if backtraces are enabled.



211
212
213
214
215
 
# File 'lib/rubygems/user_interaction.rb', line 211

def backtrace(exception)
  return unless Gem.configuration.backtrace

  @errs.puts "\t#{exception.backtrace.join "\n\t"}"
end

#choose_from_list(question, list) ⇒ Object

Choose from a list of options. question is a prompt displayed above the list. list is a list of option strings. Returns the pair [option_name, option_index].



222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
 
# File 'lib/rubygems/user_interaction.rb', line 222

def choose_from_list(question, list)
  @outs.puts question

  list.each_with_index do |item, index|
    @outs.puts " #{index + 1}. #{item}"
  end

  @outs.print "> "
  @outs.flush

  result = @ins.gets

  return nil, nil unless result

  result = result.strip.to_i - 1
  return nil, nil unless (0...list.size) === result
  [list[result], result]
end

#close ⇒ Object 



363
364
 
# File 'lib/rubygems/user_interaction.rb', line 363

def close
end

#download_reporter(*args) ⇒ Object

Return a download reporter object chosen from the current verbosity



496
497
498
499
500
501
502
 
# File 'lib/rubygems/user_interaction.rb', line 496

def download_reporter(*args)
  if [nil, false].include?(Gem.configuration.verbose) || !@outs.tty?
    SilentDownloadReporter.new(@outs, *args)
  else
    ThreadedDownloadReporter.new(@outs, *args)
  end
end

#progress_reporter(*args) ⇒ Object

Return a progress reporter object chosen from the current verbosity.



369
370
371
372
373
374
375
376
377
378
 
# File 'lib/rubygems/user_interaction.rb', line 369

def progress_reporter(*args)
  case Gem.configuration.verbose
  when nil, false
    SilentProgressReporter.new(@outs, *args)
  when true
    SimpleProgressReporter.new(@outs, *args)
  else
    VerboseProgressReporter.new(@outs, *args)
  end
end

#require_io_console ⇒ Object 



307
308
309
310
311
312
313
314
315
 
# File 'lib/rubygems/user_interaction.rb', line 307

def require_io_console
  @require_io_console ||= begin
    begin
      require "io/console"
    rescue LoadError
    end
    true
  end
end

#say(statement = "") ⇒ Object

Display a statement.



325
326
327
 
# File 'lib/rubygems/user_interaction.rb', line 325

def say(statement = "")
  @outs.puts statement
end

#terminate_interaction(status = 0) ⇒ Object

Terminate the application with exit code status, running any exit handlers that might have been defined.

Raises:



358
359
360
361
 
# File 'lib/rubygems/user_interaction.rb', line 358

def terminate_interaction(status = 0)
  close
  raise Gem::SystemExitException, status
end

#tty? ⇒ Boolean

Returns true if TTY methods should be used on this StreamUI.

Returns:

  • (Boolean) 


203
204
205
 
# File 'lib/rubygems/user_interaction.rb', line 203

def tty?
  @usetty && @ins.tty?
end