class RSpec::Support::MethodSignature
Extracts info about the number of arguments and allowed/required keyword args of a given method.
@private
Constants
- INFINITY
Attributes
Public Class Methods
# File rspec-support/lib/rspec/support/method_signature_verifier.rb, line 16 def initialize(method) @method = method @optional_kw_args = [] @required_kw_args = [] classify_parameters end
Public Instance Methods
# File rspec-support/lib/rspec/support/method_signature_verifier.rb, line 123 def arbitrary_kw_args? @allows_any_kw_args end
# File rspec-support/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
# File rspec-support/lib/rspec/support/method_signature_verifier.rb, line 131 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
Without considering what the last arg is, could it contain keyword arguments?
# File rspec-support/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
# File rspec-support/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
# File rspec-support/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
# File rspec-support/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
# File rspec-support/lib/rspec/support/method_signature_verifier.rb, line 73 def missing_kw_args_from(given_kw_args) @required_kw_args - given_kw_args end
# File rspec-support/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
# File rspec-support/lib/rspec/support/method_signature_verifier.rb, line 127 def unlimited_args? @max_non_kw_args == INFINITY end
# File rspec-support/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