Class: Class

Inherits:
Object show all
Defined in:
lib/rubypitaya/app-template/vendor/bundle/ruby/3.1.0/gems/rspec-mocks-3.12.2/lib/rspec/mocks/syntax.rb,
lib/rubypitaya/app-template/vendor/bundle/ruby/3.1.0/gems/activesupport-7.0.4/lib/active_support/core_ext/class/attribute.rb,
lib/rubypitaya/app-template/vendor/bundle/ruby/3.1.0/gems/activesupport-7.0.4/lib/active_support/core_ext/class/subclasses.rb

Overview

The legacy ‘:should` syntax adds the `any_instance` to `Class`. We generally recommend you use the newer `:expect` syntax instead, which allows you to stub any instance of a class using `allow_any_instance_of(klass)` or mock any instance using `expect_any_instance_of(klass)`.

See Also:

Instance Method Summary collapse

Instance Method Details

#any_instance ⇒ Recorder

Note:

This is only available when you have enabled the ‘should` syntax.

Used to set stubs and message expectations on any instance of a given class. Returns a [Recorder](Recorder), which records messages like ‘stub` and `should_receive` for later playback on instances of the class.

Examples:

Car.any_instance.should_receive(:go)
race = Race.new
race.cars << Car.new
race.go # assuming this delegates to all of its cars
        # this example would pass

Account.any_instance.stub(:balance) { Money.new(:USD, 25) }
Account.new.balance # => Money.new(:USD, 25))

Returns:

  • (Recorder)

See Also:




# File 'lib/rubypitaya/app-template/vendor/bundle/ruby/3.1.0/gems/rspec-mocks-3.12.2/lib/rspec/mocks/syntax.rb', line 304

#class_attribute(*attrs, instance_accessor: true, instance_reader: instance_accessor, instance_writer: instance_accessor, instance_predicate: true, default: nil) ⇒ Object

Declare a class-level attribute whose value is inheritable by subclasses. Subclasses can change their own value and it will not impact parent class.

Options

  • :instance_reader - Sets the instance reader method (defaults to true).

  • :instance_writer - Sets the instance writer method (defaults to true).

  • :instance_accessor - Sets both instance methods (defaults to true).

  • :instance_predicate - Sets a predicate method (defaults to true).

  • :default - Sets a default value for the attribute (defaults to nil).

Examples

class Base
  class_attribute :setting
end

class Subclass < Base
end

Base.setting = true
Subclass.setting            # => true
Subclass.setting = false
Subclass.setting            # => false
Base.setting                # => true

In the above case as long as Subclass does not assign a value to setting by performing Subclass.setting = something, Subclass.setting would read value assigned to parent class. Once Subclass assigns a value then the value assigned by Subclass would be returned.

This matches normal Ruby method inheritance: think of writing an attribute on a subclass as overriding the reader method. However, you need to be aware when using class_attribute with mutable structures as Array or Hash. In such cases, you don’t want to do changes in place. Instead use setters:

Base.setting = []
Base.setting                # => []
Subclass.setting            # => []

# Appending in child changes both parent and child because it is the same object:
Subclass.setting << :foo
Base.setting               # => [:foo]
Subclass.setting           # => [:foo]

# Use setters to not propagate changes:
Base.setting = []
Subclass.setting += [:foo]
Base.setting               # => []
Subclass.setting           # => [:foo]

For convenience, an instance predicate method is defined as well. To skip it, pass instance_predicate: false.

Subclass.setting?       # => false

Instances may overwrite the class value in the same way:

Base.setting = true
object = Base.new
object.setting          # => true
object.setting = false
object.setting          # => false
Base.setting            # => true

To opt out of the instance reader method, pass instance_reader: false.

object.setting          # => NoMethodError
object.setting?         # => NoMethodError

To opt out of the instance writer method, pass instance_writer: false.

object.setting = false  # => NoMethodError

To opt out of both instance methods, pass instance_accessor: false.

To set a default value for the attribute, pass default:, like so:

class_attribute :settings, default: {}



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# File 'lib/rubypitaya/app-template/vendor/bundle/ruby/3.1.0/gems/activesupport-7.0.4/lib/active_support/core_ext/class/attribute.rb', line 85

def class_attribute(*attrs, instance_accessor: true,
  instance_reader: instance_accessor, instance_writer: instance_accessor, instance_predicate: true, default: nil)

  class_methods, methods = [], []
  attrs.each do |name|
    unless name.is_a?(Symbol) || name.is_a?(String)
      raise TypeError, "#{name.inspect} is not a symbol nor a string"
    end

    class_methods << <<~RUBY # In case the method exists and is not public
      silence_redefinition_of_method def #{name}
      end
    RUBY

    methods << <<~RUBY if instance_reader
      silence_redefinition_of_method def #{name}
        defined?(@#{name}) ? @#{name} : self.class.#{name}
      end
    RUBY

    class_methods << <<~RUBY
      silence_redefinition_of_method def #{name}=(value)
        redefine_method(:#{name}) { value } if singleton_class?
        redefine_singleton_method(:#{name}) { value }
        value
      end
    RUBY

    methods << <<~RUBY if instance_writer
      silence_redefinition_of_method(:#{name}=)
      attr_writer :#{name}
    RUBY

    if instance_predicate
      class_methods << "silence_redefinition_of_method def #{name}?; !!self.#{name}; end"
      if instance_reader
        methods << "silence_redefinition_of_method def #{name}?; !!self.#{name}; end"
      end
    end
  end

  location = caller_locations(1, 1).first
  class_eval(["class << self", *class_methods, "end", *methods].join(";").tr("\n", ";"), location.path, location.lineno)

  attrs.each { |name| public_send("#{name}=", default) }
end

#descendants ⇒ Object

Returns an array with all classes that are < than its receiver.

class C; end
C.descendants # => []

class B < C; end
C.descendants # => [B]

class A < B; end
C.descendants # => [B, A]

class D < C; end
C.descendants # => [B, A, D]



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# File 'lib/rubypitaya/app-template/vendor/bundle/ruby/3.1.0/gems/activesupport-7.0.4/lib/active_support/core_ext/class/subclasses.rb', line 20

def descendants
  subclasses.concat(subclasses.flat_map(&:descendants))
end

#subclasses ⇒ Object

Returns an array with the direct children of self.

class Foo; end
class Bar < Foo; end
class Baz < Bar; end

Foo.subclasses # => [Bar]



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# File 'lib/rubypitaya/app-template/vendor/bundle/ruby/3.1.0/gems/activesupport-7.0.4/lib/active_support/core_ext/class/subclasses.rb', line 38

def subclasses
  descendants.select { |descendant| descendant.superclass == self }
end