Class: Object Private

Inherits:
BasicObject
Extended by:
MacOSVersionErrorCompat
Defined in:
extend/blank.rb,
macos_version.rb,
extend/object/deep_dup.rb,
extend/object/duplicable.rb

Overview

This class is part of a private API. This class may only be used in the Homebrew/brew repository. Third parties should avoid using this class if possible, as it may be removed or changed without warning.

– Most objects are cloneable, but not all. For example you can’t dup methods:

method(:puts).dup # => TypeError: allocator undefined for Method

Classes may signal their instances are not duplicable removing +dup+/+clone+ or raising exceptions from them. So, to dup an arbitrary object you normally use an optimistic approach and are ready to catch an exception, say:

arbitrary_object.dup rescue object

Rails dups objects in a few critical spots where they are not that arbitrary. That rescue is very expensive (like 40 times slower than a predicate), and it is often triggered.

That’s why we hardcode the following cases and check duplicable? instead of using that rescue idiom. ++

Instance Method Summary collapse

Methods included from MacOSVersionErrorCompat

const_missing

Methods included from Kernel

#disk_usage_readable, #ensure_executable!, #ensure_formula_installed!, #exec_browser, #exec_editor, #ignore_interrupts, #interactive_shell, #number_readable, #odebug, #odeprecated, #odie, #odisabled, #ofail, #oh1, #oh1_title, #ohai, #ohai_title, #onoe, #opoo, #paths, #pretty_duration, #pretty_installed, #pretty_outdated, #pretty_uninstalled, #quiet_system, #redact_secrets, #redirect_stdout, #require?, #safe_system, #tap_and_name_comparison, #truncate_text_to_approximate_size, #which, #which_all, #which_editor, #with_custom_locale, #with_env, #with_homebrew_path

Instance Method Details

#blank? ⇒ Boolean

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

An object is blank if it’s false, empty, or a whitespace string. For example, +nil+, ‘’, ‘ ‘, [], {}, and +false+ are all blank.

This simplifies

!address   address.empty?

to

address.blank?

Returns:

  • (Boolean) 


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# File 'extend/blank.rb', line 16

def blank?
  respond_to?(:empty?) ? !!T.unsafe(self).empty? : false
end

#deep_dup ⇒ T.self_type

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

Returns a deep copy of object if it’s duplicable. If it’s not duplicable, returns +self+.

object = Object.new dup = object.deep_dup dup.instance_variable_set(:@a, 1)

object.instance_variable_defined?(:@a) # => false dup.instance_variable_defined?(:@a) # => true

Returns:

  • (T.self_type) 


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# File 'extend/object/deep_dup.rb', line 17

def deep_dup
  duplicable? ? dup : self
end

#duplicable? ⇒ Boolean

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

Can you safely dup this object?

False for method objects; true otherwise.

Returns:

  • (Boolean) 


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# File 'extend/object/duplicable.rb', line 28

def duplicable? = true

#presence ⇒ T.self_type?

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

Returns the receiver if it’s present otherwise returns +nil+. object.presence is equivalent to

object.present? ? object : nil

For example, something like

state = params[:state] if params[:state].present? country = params[:country] if params[:country].present? region = state || country || ‘US’

becomes

region = params[:state].presence   params[:country].presence   ‘US’

Returns:

  • (T.self_type, nil) 


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# File 'extend/blank.rb', line 39

def presence
  self if present?
end

#present? ⇒ Boolean

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

An object is present if it’s not blank.

Returns:

  • (Boolean) 


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# File 'extend/blank.rb', line 22

def present? = !blank?