Method: Minitest::Spec::DSL#let

Defined in:
lib/minitest/spec.rb

#let(name, &block) ⇒ Object

Essentially, define an accessor for name with block.

Why use let instead of def? I honestly don’t know.

Raises:

  • (ArgumentError)
[View source]

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# File 'lib/minitest/spec.rb', line 248

def let name, &block
  name = name.to_s
  pre, post = "let '#{name}' cannot ", ". Please use another name."
  methods = Minitest::Spec.instance_methods.map(&:to_s) - %w[subject]
  raise ArgumentError, "#{pre}begin with 'test'#{post}" if
    name.start_with? "test"
  raise ArgumentError, "#{pre}override a method in Minitest::Spec#{post}" if
    methods.include? name

  define_method name do
    @_memoized ||= {}
    @_memoized.fetch(name) { |k| @_memoized[k] = instance_eval(&block) }
  end
end