class Pry::Hooks - pry-0.10.1 Documentation

# class Pry::Hooks

Implements a hooks system for Pry. A hook is a callable that is associated with an event. A number of events are currently provided by Pry, these include: `:when_started`, `:before_session`, `:after_session`. A hook must have a name, and is connected with an event by the `Pry::Hooks#add_hook` method. @example Adding a hook for the `:before_session` event.

    Pry.config.hooks.add_hook(:before_session, :say_hi) do
      puts "hello"
    end

### Public Class Methods

from_hash(hash) click to toggle source

Converts a hash to a `Pry::Hooks` instance. All hooks defined this way are anonymous. This functionality is primarily to provide backwards-compatibility with the old hash-based hook system in Pry versions < 0.9.8 @param [Hash] hash The hash to convert to `Pry::Hooks`. @return [Pry::Hooks] The resulting `Pry::Hooks` instance.

    # File lib/pry/hooks.rb, line 20
    def self.from_hash(hash)
      return hash if hash.instance_of?(self)
      instance = new
      hash.each do |k, v|
        instance.add_hook(k, nil, v)
      end
      instance
    end

new() click to toggle source

    # File lib/pry/hooks.rb, line 29
    def initialize
      @hooks = {}
    end

### Public Instance Methods

add_hook(event_name, hook_name, callable=nil, &block) click to toggle source

Add a new hook to be executed for the `name` even. @param [Symbol] event_name The name of the event. @param [Symbol] hook_name The name of the hook. @param [#call] callable The callable. @yield The block to use as the callable (if `callable` parameter not provided) @return [Pry:Hooks] Returns the receiver. @example

    Pry::Hooks.new.add_hook(:before_session, :say_hi) { puts "hi!" }

    # File lib/pry/hooks.rb, line 98
    def add_hook(event_name, hook_name, callable=nil, &block)
      @hooks[event_name] ||= []

      # do not allow duplicates, but allow multiple `nil` hooks
      # (anonymous hooks)
      if hook_exists?(event_name, hook_name) && !hook_name.nil?
        raise ArgumentError, "Hook with name '#{hook_name}' already defined!"
      end

      if !block && !callable
        raise ArgumentError, "Must provide a block or callable."
      end

      # ensure we only have one anonymous hook
      @hooks[event_name].delete_if { |h, k| h.nil? } if hook_name.nil?

      if block
        @hooks[event_name] << [hook_name, block]
      elsif callable
        @hooks[event_name] << [hook_name, callable]
      end

      self
    end

clear(event_name)
Alias for: delete_hooks
clear_all() click to toggle source

Remove all events and hooks, clearing out the Pry::Hooks instance completely. @example

    my_hooks = Pry::Hooks.new.add_hook(:before_session, :say_hi) { puts "hi!" }
    my_hooks.clear_all

    # File lib/pry/hooks.rb, line 219
    def clear_all
      @hooks = {}
    end

delete_hook(event_name, hook_name) click to toggle source

Delete a hook for an event. @param [Symbol] event_name The name of the event. @param [Symbol] hook_name The name of the hook.

    to delete.

@return [#call] The deleted hook. @example

    my_hooks = Pry::Hooks.new.add_hook(:before_session, :say_hi) { puts "hi!" }
    my_hooks.delete_hook(:before_session, :say_hi)

    # File lib/pry/hooks.rb, line 188
    def delete_hook(event_name, hook_name)
      @hooks[event_name] ||= []
      deleted_callable = nil

      @hooks[event_name].delete_if do |current_hook_name, callable|
        if current_hook_name == hook_name
          deleted_callable = callable
          true
        else
          false
        end
      end
      deleted_callable
    end

delete_hooks(event_name) click to toggle source

Clear all hooks functions for a given event. @param [String] event_name The name of the event. @example

    my_hooks = Pry::Hooks.new.add_hook(:before_session, :say_hi) { puts "hi!" }
    my_hooks.delete_hook(:before_session)

    # File lib/pry/hooks.rb, line 208
    def delete_hooks(event_name)
      @hooks[event_name] = []
    end

Also aliased as: clear
errors() click to toggle source

    # File lib/pry/hooks.rb, line 48
    def errors
      @errors ||= []
    end

exec_hook(event_name, *args, &block) click to toggle source

Execute the list of hooks for the `event_name` event. @param [Symbol] event_name The name of the event. @param [Array] args The arguments to pass to each hook function. @return [Object] The return value of the last executed hook. @example

    my_hooks = Pry::Hooks.new.add_hook(:before_session, :say_hi) { puts "hi!" }
    my_hooks.exec_hook(:before_session) #=> OUTPUT: "hi!"

    # File lib/pry/hooks.rb, line 130
    def exec_hook(event_name, *args, &block)
      @hooks[event_name] ||= []

      @hooks[event_name].map do |hook_name, callable|
        begin
          callable.call(*args, &block)
        rescue RescuableException => e
          errors << e
          e
        end
      end.last
    end

get_hook(event_name, hook_name) click to toggle source

Return a specific hook for a given event. @param [Symbol] event_name The name of the event. @param [Symbol] hook_name The name of the hook @return [#call] The requested hook. @example

    my_hooks = Pry::Hooks.new.add_hook(:before_session, :say_hi) { puts "hi!" }
    my_hooks.get_hook(:before_session, :say_hi).call #=> "hi!"

    # File lib/pry/hooks.rb, line 161
    def get_hook(event_name, hook_name)
      @hooks[event_name] ||= []
      hook = @hooks[event_name].find { |current_hook_name, callable| current_hook_name == hook_name }
      hook.last if hook
    end

get_hooks(event_name) click to toggle source

Return the hash of hook names / hook functions for a given event. (Note that modifying the returned hash does not alter the hooks, use add_hook/delete_hook for that). @param [Symbol] event_name The name of the event. @return [Hash] The hash of hook names / hook functions. @example

    my_hooks = Pry::Hooks.new.add_hook(:before_session, :say_hi) { puts "hi!" }
    my_hooks.get_hooks(:before_session) #=> {:say_hi=>#<Proc:0x00000101645e18@(pry):9>}

    # File lib/pry/hooks.rb, line 175
    def get_hooks(event_name)
      @hooks[event_name] ||= []
      Hash[@hooks[event_name]]
    end

hook_count(event_name) click to toggle source

Return the number of hook functions registered for the `event_name` event. @param [Symbol] event_name The name of the event. @return [Fixnum] The number of hook functions for `event_name`. @example

    my_hooks = Pry::Hooks.new.add_hook(:before_session, :say_hi) { puts "hi!" }
    my_hooks.count(:before_session) #=> 1

    # File lib/pry/hooks.rb, line 149
    def hook_count(event_name)
      @hooks[event_name] ||= []
      @hooks[event_name].size
    end

hook_exists?(event_name, hook_name) click to toggle source

@param [Symbol] event_name Name of the event. @param [Symbol] hook_name Name of the hook. @return [Boolean] Whether the hook by the name `hook_name`

    # File lib/pry/hooks.rb, line 226
    def hook_exists?(event_name, hook_name)
      !!(@hooks[event_name] && @hooks[event_name].find { |name, _| name == hook_name })
    end

initialize_copy(orig) click to toggle source

Ensure that duplicates have their @hooks object

    # File lib/pry/hooks.rb, line 34
    def initialize_copy(orig)
      hooks_dup = @hooks.dup
      @hooks.each do |k, v|
        hooks_dup[k] = v.dup
      end

      @hooks = hooks_dup
    end

merge(other) click to toggle source

Return a new `Pry::Hooks` instance containing a merge of the contents of two `Pry:Hooks` instances, @param [Pry::Hooks] other The `Pry::Hooks` instance to merge @return [Pry::Hooks] The new hash. @example

    hooks = Pry::Hooks.new.add_hook(:before_session, :say_hi) { puts "hi!" }
    Pry::Hooks.new.merge(hooks)

    # File lib/pry/hooks.rb, line 84
    def merge(other)
      self.dup.tap do |v|
        v.merge!(other)
      end
    end

merge!(other) click to toggle source

Destructively merge the contents of two `Pry:Hooks` instances. @param [Pry::Hooks] other The `Pry::Hooks` instance to merge @return [Pry:Hooks] Returns the receiver. @example

    hooks = Pry::Hooks.new.add_hook(:before_session, :say_hi) { puts "hi!" }
    Pry::Hooks.new.merge!(hooks)

    # File lib/pry/hooks.rb, line 58
    def merge!(other)
      @hooks.merge!(other.dup.hooks) do |key, v1, v2|
        merge_arrays(v1, v2)
      end

      self
    end

### Protected Instance Methods

hooks() click to toggle source

    # File lib/pry/hooks.rb, line 43
    def hooks
      @hooks
    end