Merge pull request #360 from georgebrock/gb-readline

Use Readline for user input

Author: sferik

lib/thor/base.rb

@@ -5,6 +5,7 @@
 require 'thor/invocation'
 require 'thor/parser'
 require 'thor/shell'
+require 'thor/line_editor'
 require 'thor/util'
 
 class Thor

lib/thor/line_editor.rb

@@ -0,0 +1,17 @@
+require 'thor/line_editor/basic'
+require 'thor/line_editor/readline'
+
+class Thor
+  module LineEditor
+    def self.readline(prompt, options={})
+      best_available.new(prompt, options).readline
+    end
+
+    def self.best_available
+      [
+        Thor::LineEditor::Readline,
+        Thor::LineEditor::Basic
+      ].detect(&:available?)
+    end
+  end
+end

lib/thor/line_editor/basic.rb

@@ -0,0 +1,35 @@
+class Thor
+  module LineEditor
+    class Basic
+      attr_reader :prompt, :options
+
+      def self.available?
+        true
+      end
+
+      def initialize(prompt, options)
+        @prompt = prompt
+        @options = options
+      end
+
+      def readline
+        $stdout.print(prompt)
+        get_input
+      end
+
+      private
+
+      def get_input
+        if echo?
+          $stdin.gets
+        else
+          $stdin.noecho(&:gets)
+        end
+      end
+
+      def echo?
+        options.fetch(:echo, true)
+      end
+    end
+  end
+end

lib/thor/line_editor/readline.rb

@@ -0,0 +1,84 @@
+begin
+  require 'readline'
+rescue LoadError
+end
+
+class Thor
+  module LineEditor
+    class Readline < Basic
+      def self.available?
+        Object.const_defined?(:Readline)
+      end
+
+      def readline
+        if echo?
+          ::Readline.completion_append_character = nil
+          ::Readline.completion_proc = completion_proc
+          ::Readline.readline(prompt, add_to_history?)
+        else
+          super
+        end
+      end
+
+      private
+
+      def add_to_history?
+        options.fetch(:add_to_history, true)
+      end
+
+      def completion_proc
+        if use_path_completion?
+          Proc.new { |text| PathCompletion.new(text).matches }
+        elsif completion_options.any?
+          Proc.new do |text|
+            completion_options.select { |option| option.start_with?(text) }
+          end
+        end
+      end
+
+      def completion_options
+        options.fetch(:limited_to, [])
+      end
+
+      def use_path_completion?
+        options.fetch(:path, false)
+      end
+
+      class PathCompletion
+        def initialize(text)
+          @text = text
+        end
+
+        def matches
+          relative_matches
+        end
+
+        private
+
+        attr_reader :text
+
+        def relative_matches
+          absolute_matches.map { |path| path.sub(base_path, '') }
+        end
+
+        def absolute_matches
+          Dir[glob_pattern].map do |path|
+            if File.directory?(path)
+              "#{path}/"
+            else
+              path
+            end
+          end
+        end
+
+        def glob_pattern
+          "#{base_path}#{text}*"
+        end
+
+        def base_path
+          "#{Dir.pwd}/"
+        end
+      end
+    end
+  end
+end

lib/thor/shell/basic.rb

@@ -43,13 +43,20 @@ def padding=(value)
       # If asking for sensitive information, the :echo option can be set
       # to false to mask user input from $stdin.
       #
+      # If the required input is a path, then set the path option to
+      # true. This will enable tab completion for file paths relative
+      # to the current working directory on systems that support
+      # Readline.
+      #
       # ==== Example
       # ask("What is your name?")
       #
       # ask("What is your favorite Neopolitan flavor?", :limited_to => ["strawberry", "chocolate", "vanilla"])
       #
       # ask("What is your password?", :echo => false)
       #
+      # ask("Where should the file be saved?", :path => true)
+      #
       def ask(statement, *args)
         options = args.last.is_a?(Hash) ? args.pop : {}
         color = args.first
@@ -69,11 +76,7 @@ def ask(statement, *args)
       # say("I know you knew that.")
       #
       def say(message = '', color = nil, force_new_line = (message.to_s !~ /( |\t)\Z/))
-        message = message.to_s
-        message = set_color(message, *color) if color && can_display_colors?
-
-        buffer = '  ' * padding
-        buffer << message
+        buffer = prepare_message(message, *color)
         buffer << "\n" if force_new_line && !message.end_with?("\n")
 
         stdout.print(buffer)
@@ -104,14 +107,14 @@ def say_status(status, message, log_status = true)
       # "yes".
       #
       def yes?(statement, color = nil)
-        !!(ask(statement, color) =~ is?(:yes))
+        !!(ask(statement, color, :add_to_history => false) =~ is?(:yes))
       end
 
       # Make a question the to user and returns true if the user replies "n" or
       # "no".
       #
       def no?(statement, color = nil)
-        !!(ask(statement, color) =~ is?(:no))
+        !!(ask(statement, color, :add_to_history => false) =~ is?(:no))
       end
 
       # Prints values in columns
@@ -231,7 +234,10 @@ def file_collision(destination) # rubocop:disable MethodLength
         options = block_given? ? '[Ynaqdh]' : '[Ynaqh]'
 
         loop do
-          answer = ask %[Overwrite #{destination}? (enter "h" for help) #{options}]
+          answer = ask(
+            %[Overwrite #{destination}? (enter "h" for help) #{options}],
+            :add_to_history => false
+          )
 
           case answer
           when is?(:yes), is?(:force), ''
@@ -283,6 +289,11 @@ def set_color(string, *args) #:nodoc:
 
     protected
 
+      def prepare_message(message, *color)
+        spaces = "  " * padding
+        spaces + set_color(message.to_s, *color)
+      end
+
       def can_display_colors?
         false
       end
@@ -296,10 +307,6 @@ def stdout
         $stdout
       end
 
-      def stdin
-        $stdin
-      end
-
       def stderr
         $stderr
       end
@@ -383,13 +390,8 @@ def as_unicode
       def ask_simply(statement, color, options)
         default = options[:default]
         message = [statement, ("(#{default})" if default), nil].uniq.join(' ')
-        say(message, color)
-
-        result = if options[:echo] == false
-                   stdin.noecho(&:gets)
-                 else
-                   stdin.gets
-                 end
+        message = prepare_message(message, color)
+        result = Thor::LineEditor.readline(message, options)
 
         return unless result
 

lib/thor/shell/color.rb

@@ -77,7 +77,9 @@ class Color < Basic
       #   :on_cyan
       #   :on_white
       def set_color(string, *colors)
-        if colors.all? { |color| color.is_a?(Symbol) || color.is_a?(String) }
+        if colors.compact.empty? || !can_display_colors?
+          string
+        elsif colors.all? { |color| color.is_a?(Symbol) || color.is_a?(String) }
           ansi_colors = colors.map { |color| lookup_color(color) }
           "#{ansi_colors.join}#{string}#{CLEAR}"
         else

spec/actions/create_file_spec.rb

@@ -101,32 +101,30 @@ def silence!
         end
 
         it 'shows conflict status to the user' do
-          expect(create_file('doc/config.rb')).not_to be_identical
-          expect($stdin).to receive(:gets).and_return('s')
           file = File.join(destination_root, 'doc/config.rb')
+          expect(create_file('doc/config.rb')).not_to be_identical
+          expect(Thor::LineEditor).to receive(:readline).with("Overwrite #{file}? (enter \"h\" for help) [Ynaqdh] ", anything).and_return('s')
 
           content = invoke!
           expect(content).to match(/conflict  doc\/config\.rb/)
-          expect(content).to match(/Overwrite #{file}\? \(enter "h" for help\) \[Ynaqdh\]/)
           expect(content).to match(/skip  doc\/config\.rb/)
         end
 
         it 'creates the file if the file collision menu returns true' do
           create_file('doc/config.rb')
-          expect($stdin).to receive(:gets).and_return('y')
+          expect(Thor::LineEditor).to receive(:readline).and_return('y')
           expect(invoke!).to match(/force  doc\/config\.rb/)
         end
 
         it 'skips the file if the file collision menu returns false' do
           create_file('doc/config.rb')
-          expect($stdin).to receive(:gets).and_return('n')
+          expect(Thor::LineEditor).to receive(:readline).and_return('n')
           expect(invoke!).to match(/skip  doc\/config\.rb/)
         end
 
         it 'executes the block given to show file content' do
           create_file('doc/config.rb')
-          expect($stdin).to receive(:gets).and_return('d')
-          expect($stdin).to receive(:gets).and_return('n')
+          expect(Thor::LineEditor).to receive(:readline).and_return('d', 'n')
           expect(@base.shell).to receive(:system).with(/diff -u/)
           invoke!
         end

spec/helper.rb

@@ -67,5 +67,14 @@ def destination_root
     File.join(File.dirname(__FILE__), 'sandbox')
   end
 
+  # This code was adapted from Ruby on Rails, available under MIT-LICENSE
+  # Copyright (c) 2004-2013 David Heinemeier Hansson
+  def silence_warnings
+    old_verbose, $VERBOSE = $VERBOSE, nil
+    yield
+  ensure
+    $VERBOSE = old_verbose
+  end
+
   alias silence capture
 end

spec/line_editor/basic_spec.rb

@@ -0,0 +1,28 @@
+require 'helper'
+
+describe Thor::LineEditor::Basic do
+  describe '.available?' do
+    it 'returns true' do
+      expect(Thor::LineEditor::Basic).to be_available
+    end
+  end
+
+  describe '#readline' do
+    it 'uses $stdin and $stdout to get input from the user' do
+      expect($stdout).to receive(:print).with('Enter your name ')
+      expect($stdin).to receive(:gets).and_return('George')
+      expect($stdin).not_to receive(:noecho)
+      editor = Thor::LineEditor::Basic.new('Enter your name ', {})
+      expect(editor.readline).to eq('George')
+    end
+
+    it 'disables echo when asked to' do
+      expect($stdout).to receive(:print).with('Password: ')
+      noecho_stdin = double('noecho_stdin')
+      expect(noecho_stdin).to receive(:gets).and_return('secret')
+      expect($stdin).to receive(:noecho).and_yield(noecho_stdin)
+      editor = Thor::LineEditor::Basic.new('Password: ', :echo => false)
+      expect(editor.readline).to eq('secret')
+    end
+  end
+end