Class: RSpec::Support::MethodSignature

Inherits:
Object
  • Object
show all
Defined in:
lib/rspec/support/method_signature_verifier.rb,
lib/rspec/support/method_signature_verifier.rb,
lib/rspec/support/method_signature_verifier.rb

Overview

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

Direct Known Subclasses

BlockSignature

Constant Summary collapse

INFINITY = 
1 / 0.0

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(method) ⇒ MethodSignature

Returns a new instance of MethodSignature.



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# File 'lib/rspec/support/method_signature_verifier.rb', line 16

def initialize(method)
  @method           = method
  @optional_kw_args = []
  @required_kw_args = []
  classify_parameters
end

Instance Attribute Details

#max_non_kw_args ⇒ Object (readonly)

rubocop:disable Metrics/ClassLength



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# File 'lib/rspec/support/method_signature_verifier.rb', line 14

def max_non_kw_args
  @max_non_kw_args
end

#min_non_kw_args ⇒ Object (readonly)

rubocop:disable Metrics/ClassLength



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# File 'lib/rspec/support/method_signature_verifier.rb', line 14

def min_non_kw_args
  @min_non_kw_args
end

#optional_kw_args ⇒ Object (readonly)

rubocop:disable Metrics/ClassLength



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# File 'lib/rspec/support/method_signature_verifier.rb', line 14

def optional_kw_args
  @optional_kw_args
end

#required_kw_args ⇒ Object (readonly)

rubocop:disable Metrics/ClassLength



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# File 'lib/rspec/support/method_signature_verifier.rb', line 14

def required_kw_args
  @required_kw_args
end

Instance Method Details

#arbitrary_kw_args? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rspec/support/method_signature_verifier.rb', line 123

def arbitrary_kw_args?
  @allows_any_kw_args
end

#classify_arity(arity = @method.arity) ⇒ Object Also known as: classify_parameters 



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# File 'lib/rspec/support/method_signature_verifier.rb', line 38

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

#could_contain_kw_args? ⇒ Boolean

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

Returns:

  • (Boolean) 


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# File 'lib/rspec/support/method_signature_verifier.rb', line 117

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 ⇒ Object 



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# File 'lib/rspec/support/method_signature_verifier.rb', line 51

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) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rspec/support/method_signature_verifier.rb', line 84

def has_kw_args_in?(args)
  # If the last arg is a hash, depending on the signature it could be kw_args or a positional parameter.
  return false unless Hash === args.last && could_contain_kw_args?(args)

  # If the position of the hash is beyond the count of required and optional positional
  # args then it is the kwargs hash
  return true if args.count > @max_non_kw_args

  # This is the proper way to disambiguate between positional args and keywords hash
  # but relies on beginning of the call chain annotating the method with
  # ruby2_keywords, so only use it for positive feedback as without the annotation
  # this is always false
  return true if Hash.ruby2_keywords_hash?(args[-1])

  # Otherwise, the hash could be defined kw_args or an optional positional parameter
  # inspect the keys against known kwargs to determine what it is
  # Note: the problem with this is that if a user passes only invalid keyword args,
  #       rspec no longer detects is and will assign this to a positional argument
  return arbitrary_kw_args? || args.last.keys.all? { |x| @allowed_kw_args.include?(x) }
end

#invalid_kw_args_from(_given_kw_args) ⇒ Object 



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# File 'lib/rspec/support/method_signature_verifier.rb', line 77

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) ⇒ Object 



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# File 'lib/rspec/support/method_signature_verifier.rb', line 73

def missing_kw_args_from(given_kw_args)
  @required_kw_args - given_kw_args
end

#non_kw_args_arity_description ⇒ Object 



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# File 'lib/rspec/support/method_signature_verifier.rb', line 23

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? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rspec/support/method_signature_verifier.rb', line 127

def unlimited_args?
  @max_non_kw_args == INFINITY
end

#valid_non_kw_args?(positional_arg_count, optional_max_arg_count = positional_arg_count) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rspec/support/method_signature_verifier.rb', line 31

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