Merge branch 'master' into add-clear-screen-commandadd-clear-screen-command

9 files changed, 263 insertions, 41 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 10670063..f44729fb 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,7 +1,12 @@
 ### HEAD
 
 * Add clear-screen command ([#1630](https://github.com/pry/pry/pull/1630))
-* Add `Pry::Prompt.add_prompt()`, `Pry::Prompt.get_prompt()`, and `Pry::Prompt.remove_prompt()`, for integrating custom prompts with Pry ([#1628](https://github.com/pry/pry/pull/1628))
+* Add 'alias-prompt' command.
+
+* Add `Pry::Prompt.[]`, `Pry::Prompt.add_prompt()`, `Pry::Prompt.alias_prompt()` and
+  `Pry::Prompt.remove_prompt()`, plus more, for integrating custom prompts with Pry
+  ([#1628](https://github.com/pry/pry/pull/1628)). See Pry::Prompt for complete details.
+
 * Add text helpers for background colors ([#1624](https://github.com/pry/pry/pull/1624))
 * Fix string literal methods completion. ([#1590](https://github.com/pry/pry/pull/1590))
 * Make sure Pry::WrappedModule::Candidate#source_location returns non-nil value when `.name` has
diff --git a/Gemfile b/Gemfile
index 43c0d13f..7c199855 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,11 +2,9 @@ source 'https://rubygems.org'
 gemspec
 gem 'rake',  '~> 10.0'
 
-# For Guard
 group :development do
   gem 'gist'
   gem 'yard'
-  gem 'rb-inotify', :require => false
   gem 'rb-fsevent', :require => false
 end
 
diff --git a/lib/pry/commands/alias_prompt.rb b/lib/pry/commands/alias_prompt.rb
new file mode 100644
index 00000000..a5f7a5ab
--- /dev/null
+++ b/lib/pry/commands/alias_prompt.rb
@@ -0,0 +1,33 @@
+class Pry
+  class Command::AliasPrompt < Pry::ClassCommand
+    match "alias-prompt"
+    group 'Input and Output'
+    description "Create an alternative alias for a prompt"
+    banner <<-BANNER
+    alias-prompt PROMPT_NAME ALIAS_PROMPT
+
+    Create an alternative alias for a prompt that can be seen from list-prompts and
+    used by the change-prompt commands.
+    BANNER
+
+    command_options argument_required: true
+
+    def process(prompt_name, alias_name)
+      if not args_ok?([prompt_name, alias_name])
+        return output.puts help
+      end
+      if Pry::Prompt[prompt_name]
+        Pry::Prompt.alias_prompt prompt_name, alias_name
+        output.puts "Alias '#{alias_name}' created"
+      else
+        raise Pry::CommandError, "prompt #{prompt_name} cannot be aliased because it doesn't exist."
+      end
+    end
+
+    private
+    def args_ok?(args)
+      args.size == 2 and args.all?{|s| String === s}
+    end
+    Pry::Commands.add_command(self)
+  end
+end
diff --git a/lib/pry/commands/change_prompt.rb b/lib/pry/commands/change_prompt.rb
index 4fe32d71..859825a2 100644
--- a/lib/pry/commands/change_prompt.rb
+++ b/lib/pry/commands/change_prompt.rb
@@ -11,16 +11,29 @@ class Pry::Command::ChangePrompt < Pry::ClassCommand
   BANNER
 
   def process(prompt)
-    if prompt_map.key?(prompt)
-      _pry_.prompt = prompt_map[prompt][:value]
+    prompts = Pry::Prompt.all_by_name(prompt)
+    if prompts.size == 1
+      _pry_.prompt = prompts[0]
+    elsif prompts.size > 1
+      multiple_choice(prompts)
     else
       raise Pry::CommandError, "'#{prompt}' isn't a known prompt!"
     end
   end
 
   private
-  def prompt_map
-    Pry::Prompt::PROMPT_MAP
+  def multiple_choice(prompts)
+    _pry_.pager.page "Multiple aliases found, please choose:\n"
+    prompts.each.with_index(1) do |prompt, i|
+      _pry_.pager.page "#{i}) #{prompt.name} => #{prompt.alias_for}"
+    end
+    output.write "Choice: "
+    reply = (_pry_.input.respond_to?(:gets) ? _pry_.input.gets : _pry_.input.readline).strip
+    if reply =~ /^[1-9][0-9]*$/ and reply.to_i <= prompts.size
+      _pry_.prompt = prompts[reply.to_i-1]
+    else
+      multiple_choice(prompts)
+    end
   end
   Pry::Commands.add_command(self)
 end
diff --git a/lib/pry/commands/list_prompts.rb b/lib/pry/commands/list_prompts.rb
index 9177a629..b8c2b29b 100644
--- a/lib/pry/commands/list_prompts.rb
+++ b/lib/pry/commands/list_prompts.rb
@@ -10,26 +10,28 @@ class Pry::Command::ListPrompts < Pry::ClassCommand
   BANNER
 
   def process
-    output.puts heading("Available prompts") + "\n"
-    prompt_map.each do |name, prompt|
-      output.write "Name: #{text.bold(name)}"
-      output.puts selected_prompt?(prompt) ? selected_text : ""
-      output.puts prompt[:description]
+    output.puts heading("Available prompts") + "\n\n"
+    all_prompts.each do |prompt|
+      next if prompt.alias?
+      aliases = Pry::Prompt.aliases_for(prompt.name)
+      output.write "Name: #{text.bold(prompt.name)}"
+      output.puts selected_prompt?([prompt].concat(aliases)) ? text.green(" [active]") : ""
+      output.puts "Aliases: #{aliases.map {|s| text.bold(s.name) }.join(',')}" if aliases.any?
+      output.puts prompt.description
       output.puts
     end
   end
 
   private
-  def prompt_map
-    Pry::Prompt::PROMPT_MAP
-  end
 
-  def selected_text
-    text.red " (selected) "
+  def all_prompts
+    Pry::Prompt.all_prompts
   end
 
-  def selected_prompt?(prompt)
-    _pry_.prompt == prompt[:value]
+  def selected_prompt?(prompts)
+    prompts.any? do |prompt|
+      _pry_.prompt == prompt or _pry_.prompt == prompt.proc_array
+    end
   end
   Pry::Commands.add_command(self)
 end
diff --git a/lib/pry/config/default.rb b/lib/pry/config/default.rb
index e4ae3fb6..1a653520 100644
--- a/lib/pry/config/default.rb
+++ b/lib/pry/config/default.rb
@@ -16,7 +16,7 @@ class Pry::Config::Default
       Pry::DEFAULT_PROMPT_NAME
     },
     prompt: proc {
-      Pry::DEFAULT_PROMPT
+      Pry::Prompt['default']
     },
     prompt_safe_objects: proc {
       Pry::DEFAULT_PROMPT_SAFE_OBJECTS
diff --git a/lib/pry/prompt.rb b/lib/pry/prompt.rb
index 2d8bcb36..ea71b346 100644
--- a/lib/pry/prompt.rb
+++ b/lib/pry/prompt.rb
@@ -1,6 +1,72 @@
+require 'set'
 module Pry::Prompt
   extend self
   PROMPT_MAP = {}
+  private_constant :PROMPT_MAP
+  AliasError = Class.new(RuntimeError)
+  PromptInfo = Struct.new(:name, :description, :proc_array, :alias_for) do
+    #
+    # @return [Boolean]
+    #   Returns true if the prompt is an alias of another prompt.
+    #
+    def alias?
+      alias_for != nil
+    end
+
+    def <=>(other)
+      name == other.alias_for ? 1 : 0
+    end
+
+    def to_a
+      proc_array
+    end
+
+    def eql?(other)
+      return false if not Pry::Prompt::PromptInfo === other
+      # Aliases are eql?
+      [:proc_array].all? {|m|  public_send(m) == other.public_send(m) }
+    end
+  end
+
+  #
+  # @return [Array<PromptInfo>]
+  #   Returns an Array of {PromptInfo} objects.
+  #
+  def all_prompts
+    PROMPT_MAP.values.map{|s| s.to_a}.flatten
+  end
+
+  #
+  # @param [String] prompt
+  #   The name of a prompt.
+  #
+  # @return [Array<PromptInfo>]
+  #   Returns an array of aliases for _prompt_, as {PromptInfo} objects.
+  #
+  def aliases_for(prompt)
+    all_prompts.select{|prompt_info| prompt_info.alias_for == prompt.to_s}
+  end
+
+  #
+  # @return [Array<PromptInfo>]
+  #   Returns an array of all prompt aliases, as {PromptInfo} objects.
+  #
+  def aliased_prompts
+    all_prompts.select(&:alias?)
+  end
+
+  #
+  #  @param [Array<Proc,Proc>] proc_array
+  #    An array in the form of [proc{}, proc{}]
+  #
+  #  @return [PromptInfo]
+  #    Returns the first {PromptInfo} object who holds value eql? to `proc_array`.
+  #
+  def first_matching_proc_array(proc_array)
+    all_prompts.find do |prompt|
+      prompt.proc_array == proc_array and not prompt.alias?
+    end
+  end
 
   #
   # Integrate a custom prompt with Pry.
@@ -17,23 +83,34 @@ module Pry::Prompt
   #  A prompt in the form of [proc {}, proc {}].
   #
   def add_prompt(name, description, value)
-    PROMPT_MAP[name.to_s] = {
-      value: value,
-      description: description
-    }
+    PROMPT_MAP[name.to_s] = SortedSet.new [PromptInfo.new(name.to_s, description.to_s, value, nil)]
   end
 
   #
   # @example
   #
   #   # .pryrc
-  #   Pry.config.prompt = Pry::Prompt.get_prompt('simple')
+  #   Pry.configure do |config|
+  #     config.prompt = Pry::Prompt['simple'].proc_array
+  #   end
   #
-  # @return [Array<Proc,Proc>]
-  #   Returns a prompt in the form of [proc{}, proc{}]
+  # @return [PromptInfo]
+  #   Returns a prompt in the form of a PromptInfo object.
   #
-  def get_prompt(name)
-    PROMPT_MAP.key?(name.to_s) and PROMPT_MAP[name.to_s][:value]
+  def [](name)
+    all_prompts.find {|prompt| prompt.name == name.to_s }
+  end
+
+  #
+  # @param [String] name
+  #   The name of a prompt.
+  #
+  # @return [Array<PromptInfo>]
+  #   An array of {PromptInfo} objects.
+  #
+  def all_by_name(name)
+    name = name.to_s
+    all_prompts.select{|prompt| prompt.name == name}
   end
 
   #
@@ -41,6 +118,9 @@ module Pry::Prompt
   # It will no longer be visible in the output of "list-prompts" or usable with the
   # "change-prompt" command.
   #
+  # @note
+  #   Aliases are also removed.
+  #
   # @param [String] name
   #   The name of a prompt.
   #
@@ -48,7 +128,44 @@ module Pry::Prompt
   #   Returns truthy if a prompt was deleted, otherwise nil.
   #
   def remove_prompt(name)
-    PROMPT_MAP.delete name.to_s if PROMPT_MAP.key?(name.to_s)
+    prompt = self[name.to_s]
+    PROMPT_MAP.delete name.to_s if prompt
+  end
+
+  #
+  # Provide alternative name for a prompt, which can be used from the list-prompts
+  # and change-prompt commands.
+  #
+  # @param [String] prompt_name
+  #   The name of the prompt to alias.
+  #
+  # @param [String] aliased_prompt
+  #   The name of the aliased prompt.
+  #
+  def alias_prompt(prompt_name, aliased_prompt)
+    prompt_name = prompt_name.to_s
+    prompt = self[prompt_name]
+    if not prompt
+      raise AliasError, "prompt '#{prompt}' cannot be aliased because it doesn't exist"
+    elsif prompt.alias?
+      prompt_name = prompt.alias_for
+    end
+    PROMPT_MAP[prompt_name].add PromptInfo.new *[aliased_prompt.to_s, prompt.description,
+                                                 prompt.proc_array, prompt_name]
+  end
+
+  #
+  # @param [String] alias_name
+  #   Name of a prompt alias.
+  #
+  # @return [Integer]
+  #   Returns the number of removed aliases.
+  #
+  def remove_alias(alias_name)
+    alias_name = alias_name.to_s
+    all_prompts.count do |prompt|
+      PROMPT_MAP[prompt.alias_for].delete(prompt) if prompt.alias? and prompt.name == alias_name
+    end
   end
 
   add_prompt "default",
diff --git a/lib/pry/pry_instance.rb b/lib/pry/pry_instance.rb
index 0ee7b790..4ffe4c58 100644
--- a/lib/pry/pry_instance.rb
+++ b/lib/pry/pry_instance.rb
@@ -88,14 +88,16 @@ class Pry
   #    self.prompt = Pry::SIMPLE_PROMPT
   #    self.prompt # => Pry::SIMPLE_PROMPT
   #
-  # @return [Array<Proc>] Current prompt.
+  # @return [Pry::Prompt::PromptInfo, Array<Proc, Proc>] Current prompt.
   def prompt
-    prompt_stack.last
+    proc_array = prompt_stack.last
+    Pry::Prompt.first_matching_proc_array(proc_array) or proc_array
   end
 
   def prompt=(new_prompt)
+    new_prompt = new_prompt.to_a
     if prompt_stack.empty?
-      push_prompt new_prompt
+      push_prompt(new_prompt)
     else
       prompt_stack[-1] = new_prompt
     end
diff --git a/spec/prompt_spec.rb b/spec/prompt_spec.rb
index 45c21fd6..55692703 100644
--- a/spec/prompt_spec.rb
+++ b/spec/prompt_spec.rb
@@ -5,8 +5,12 @@ RSpec.describe Pry::Prompt do
     [proc{},proc{}]
   end
 
+  let(:prompt_desc) do
+    "$my custom prompt description$"
+  end
+
   before do
-    described_class.add_prompt "prompt-name", "prompt description", prompt_value
+    described_class.add_prompt "prompt-name", prompt_desc, prompt_value
   end
 
   after do
@@ -14,20 +18,68 @@ RSpec.describe Pry::Prompt do
   end
 
   describe ".add_prompt" do
-    specify "it adds a new prompt to Pry" do
-      new_prompt = described_class::PROMPT_MAP['prompt-name']
-      expect(new_prompt).to eq(description: "prompt description", value: prompt_value)
+    specify "adds new Prompt" do
+      expect(described_class['prompt-name']).to be_instance_of(Pry::Prompt::PromptInfo)
+    end
+
+    specify "prompt appears in list-prompts" do
       expect(pry_eval("list-prompts")).to include("prompt-name")
-      expect(pry_eval("list-prompts")).to include("prompt description")
-      expect(pry_eval("change-prompt prompt-name", "_pry_.prompt")).to eq(prompt_value)
+      expect(pry_eval("list-prompts")).to include(prompt_desc)
+    end
+
+    specify "prompt is changed to via change-prompt" do
+      expect(pry_eval("change-prompt prompt-name", "_pry_.prompt")).to eq(described_class['prompt-name'])
     end
   end
 
   describe ".remove_prompt" do
-    specify "it removes a prompt from Pry" do
+    specify "removes a prompt" do
+      described_class.remove_prompt 'prompt-name'
+      expect(described_class['prompt-name']).to eq(nil)
+    end
+
+    specify "prompt disappears from list-prompts" do
       described_class.remove_prompt 'prompt-name'
       expect(pry_eval("list-prompts")).to_not include("prompt-name")
-      expect(pry_eval("list-prompts")).to_not include("prompt description")
+    end
+
+    specify "does not remove aliases" do
+      described_class.alias_prompt "prompt-name", "prompt-alias"
+      described_class.remove_prompt 'prompt-alias'
+      expect(described_class['prompt-alias']).to_not be_nil
+    end
+  end
+
+  describe ".alias_prompt" do
+    before do
+      described_class.alias_prompt "prompt-name", "prompt-alias"
+    end
+
+    specify "creates alias" do
+      expect(described_class.aliases_for("prompt-name")).to eq([described_class['prompt-alias']])
+    end
+
+    specify "alias appears in list-prompts" do
+      expect(pry_eval("list-prompts")).to include("Aliases: prompt-alias")
+    end
+
+    specify "alias is changed to via change-prompt" do
+      expect(pry_eval("change-prompt prompt-alias", "_pry_.prompt")).to eq(described_class['prompt-name'])
+    end
+  end
+
+  describe ".remove_alias" do
+    before do
+      described_class.alias_prompt "prompt-name", "prompt-alias"
+    end
+
+    specify "returns number of removed aliases" do
+      expect(described_class.remove_alias("prompt-alias")).to eq(1)
+    end
+
+    specify "removes alias from Pry::Prompt" do
+      expect(described_class.remove_alias("prompt-alias")).to eq(1)
+      expect(described_class['prompt-alias']).to eq(nil)
     end
   end
 end