class RSpec::Support::MethodSignature

Extracts info about the number of arguments and allowed/required keyword args of a given method.

@private

Constants

INFINITY

Attributes

max_non_kw_args[R]
min_non_kw_args[R]
optional_kw_args[R]
required_kw_args[R]

Public Class Methods

new(method) click to toggle source
# File lib/rspec/support/method_signature_verifier.rb, line 14
def initialize(method)
  @method           = method
  @optional_kw_args = []
  @required_kw_args = []
  classify_parameters
end

Public Instance Methods

arbitrary_kw_args?() click to toggle source
# File lib/rspec/support/method_signature_verifier.rb, line 93
def arbitrary_kw_args?
  @allows_any_kw_args
end
classify_arity(arity=@method.arity) click to toggle source
# File lib/rspec/support/method_signature_verifier.rb, line 36
def classify_arity(arity=@method.arity)
  if arity < 0
    # `~` inverts the one's complement and gives us the
    # number of required args
    @min_non_kw_args = ~arity
    @max_non_kw_args = INFINITY
  else
    @min_non_kw_args = arity
    @max_non_kw_args = arity
  end
end
classify_parameters() click to toggle source
# File lib/rspec/support/method_signature_verifier.rb, line 101
def classify_parameters
  optional_non_kw_args = @min_non_kw_args = 0
  @allows_any_kw_args = false

  @method.parameters.each do |(type, name)|
    case type
    # def foo(a:)
    when :keyreq  then @required_kw_args << name
    # def foo(a: 1)
    when :key     then @optional_kw_args << name
    # def foo(**kw_args)
    when :keyrest then @allows_any_kw_args = true
    # def foo(a)
    when :req     then @min_non_kw_args += 1
    # def foo(a = 1)
    when :opt     then optional_non_kw_args += 1
    # def foo(*a)
    when :rest    then optional_non_kw_args = INFINITY
    end
  end

  @max_non_kw_args = @min_non_kw_args  + optional_non_kw_args
  @allowed_kw_args = @required_kw_args + @optional_kw_args
end
could_contain_kw_args?(args) click to toggle source

Without considering what the last arg is, could it contain keyword arguments?

# File lib/rspec/support/method_signature_verifier.rb, line 88
def could_contain_kw_args?(args)
  return false if args.count <= min_non_kw_args
  @allows_any_kw_args || @allowed_kw_args.any?
end
description() click to toggle source
# File lib/rspec/support/method_signature_verifier.rb, line 49
def description
  @description ||= begin
    parts = []

    unless non_kw_args_arity_description == "0"
      parts << "arity of #{non_kw_args_arity_description}"
    end

    if @optional_kw_args.any?
      parts << "optional keyword args (#{@optional_kw_args.map(&:inspect).join(", ")})"
    end

    if @required_kw_args.any?
      parts << "required keyword args (#{@required_kw_args.map(&:inspect).join(", ")})"
    end

    parts << "any additional keyword args" if @allows_any_kw_args

    parts.join(" and ")
  end
end
has_kw_args_in?(args) click to toggle source
# File lib/rspec/support/method_signature_verifier.rb, line 80
def has_kw_args_in?(args)
  Hash === args.last &&
    could_contain_kw_args?(args) &&
    (args.last.empty? || args.last.keys.any? { |x| x.is_a?(Symbol) })
end
invalid_kw_args_from(given_kw_args) click to toggle source
# File lib/rspec/support/method_signature_verifier.rb, line 75
def invalid_kw_args_from(given_kw_args)
  return [] if @allows_any_kw_args
  given_kw_args - @allowed_kw_args
end
missing_kw_args_from(given_kw_args) click to toggle source
# File lib/rspec/support/method_signature_verifier.rb, line 71
def missing_kw_args_from(given_kw_args)
  @required_kw_args - given_kw_args
end
non_kw_args_arity_description() click to toggle source
# File lib/rspec/support/method_signature_verifier.rb, line 21
def non_kw_args_arity_description
  case max_non_kw_args
  when min_non_kw_args then min_non_kw_args.to_s
  when INFINITY then "#{min_non_kw_args} or more"
  else "#{min_non_kw_args} to #{max_non_kw_args}"
  end
end
unlimited_args?() click to toggle source
# File lib/rspec/support/method_signature_verifier.rb, line 97
def unlimited_args?
  @max_non_kw_args == INFINITY
end
valid_non_kw_args?(positional_arg_count, optional_max_arg_count=positional_arg_count) click to toggle source
# File lib/rspec/support/method_signature_verifier.rb, line 29
def valid_non_kw_args?(positional_arg_count, optional_max_arg_count=positional_arg_count)
  return true if positional_arg_count.nil?

  min_non_kw_args <= positional_arg_count &&
    optional_max_arg_count <= max_non_kw_args
end