Class: EasyPrompt

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

Overview

EasyPrompt is a utility for command-line scripts. It handles prompts and default values, and also provides a testing facility for mocking out the command-line user.

For example, here’s an irb session that illustrates what EasyPrompt does:

irb(main):001:0> require 'easyprompt'
=> true
irb(main):002:0> prompt = EasyPrompt.new
=> #<EasyPrompt:0x5a42a0 @stdout=#<EasyPrompt::MockableStdout:0x5a3e04>>
irb(main):003:0> fname = prompt.ask( "What's your first name?" )
What's your first name? John
=> "John"
irb(main):004:0> lname = prompt.ask( "What's your last name?", "Doe" )
What's your last name? [Doe] 
=> "Doe"
irb(main):005:0> correct = prompt.ask( "Is your name #{ fname } #{ lname }?", true, :boolean )
Is your name John Doe? [y] 
=> true

In the first example, we ask for the user’s first name and get “John” as the response. In the second example, we supply the default of “Doe”, which the user chooses by just pressing the “Enter” key. In the third example, we supply the default of true, which the user chooses as well. We received the boolean value true as opposed to the string “true” or “y”, because we specified :boolean as the response_class.

Defined Under Namespace

Classes: MockCommandLineUser, MockableStdin, MockableStdout

Constant Summary collapse

Version = 
'0.1.0'

Instance Method Summary collapse

Constructor Details

#initialize ⇒ EasyPrompt

Returns a new instance of EasyPrompt.



25
 
# File 'lib/easyprompt.rb', line 25

def initialize; @stdout = MockableStdout.get_mockable_stdout; end

Instance Method Details

#ask(msg, default = nil, response_class = :string) ⇒ Object

Asks the user for input.

msg

The prompt that tells the user what information to enter next.

default

The default value that will be returned if the user enters a newline (usually by pressing “Enter”) without typing any information. The default value will be displayed in square brackets after msg.

response_class

The sort of value that EasyPrompt#ask should return. Valid response classes are:

:string

This is the default.

:boolean

Values will be turned into true or false depending on whether the user enters “y” or “n”.



33
34
35
36
37
38
39
40
41
42
43
44
 
# File 'lib/easyprompt.rb', line 33

def ask( msg, default = nil, response_class = :string )
	@stdout.write( prompt( msg, default, response_class ) + ' ' )
	stdin = MockableStdin.get_mockable_stdin
	response = stdin.gets
	response.chomp!
	if response == ''
		response = default
	else
		response = response =~ /^y/i if response_class == :boolean
	end
	response
end

#prompt(msg, default = nil, response_class = :string) ⇒ Object

:nodoc:



46
47
48
49
50
51
52
53
54
55
56
57
 
# File 'lib/easyprompt.rb', line 46

def prompt( msg, default = nil, response_class = :string ) #:nodoc:
	prompt = msg
	unless default.nil?
		if response_class == :boolean
			default_str = default ? 'y' : 'n'
		else
			default_str = default.to_s
		end
		prompt += " [#{ default_str }]"
	end
	prompt
end