class RSpec::Mocks::ArgumentListMatcher

Wrapper for matching arguments against a list of expected values. Used by the `with` method on a `MessageExpectation`:

expect(object).to receive(:message).with(:a, 'b', 3)
object.message(:a, 'b', 3)

Values passed to `with` can be literal values or argument matchers that match against the real objects .e.g.

expect(object).to receive(:message).with(hash_including(:a => 'b'))

Can also be used directly to match the contents of any `Array`. This enables 3rd party mocking libs to take advantage of rspec's argument matching without using the rest of rspec-mocks.

require 'rspec/mocks/argument_list_matcher'
include RSpec::Mocks::ArgumentMatchers

arg_list_matcher = RSpec::Mocks::ArgumentListMatcher.new(123, hash_including(:a => 'b'))
arg_list_matcher.args_match?(123, :a => 'b')

This class is immutable.

@see ArgumentMatchers

Constants

MATCH_ALL

Value that will match all argument lists.

@private

Attributes

expected_args[R]

@private

Public Class Methods

new(*expected_args) click to toggle source

@api public @param [Array] expected_args a list of expected literals and/or argument matchers

Initializes an `ArgumentListMatcher` with a collection of literal values and/or argument matchers.

@see ArgumentMatchers @see args_match?

# File lib/rspec/mocks/argument_list_matcher.rb, line 45
def initialize(*expected_args)
  @expected_args = expected_args
  ensure_expected_args_valid!
end

Public Instance Methods

args_match?(*args) click to toggle source

@api public @param [Array] args

Matches each element in the `expected_args` against the element in the same position of the arguments passed to `new`.

@see initialize

# File lib/rspec/mocks/argument_list_matcher.rb, line 57
def args_match?(*args)
  Support::FuzzyMatcher.values_match?(resolve_expected_args_based_on(args), args)
end
resolve_expected_args_based_on(actual_args) click to toggle source

@private Resolves abstract arg placeholders like `no_args` and `any_args` into a more concrete arg list based on the provided `actual_args`.

# File lib/rspec/mocks/argument_list_matcher.rb, line 64
def resolve_expected_args_based_on(actual_args)
  return [] if [ArgumentMatchers::NoArgsMatcher::INSTANCE] == expected_args

  any_args_index = expected_args.index { |a| ArgumentMatchers::AnyArgsMatcher::INSTANCE == a }
  return expected_args unless any_args_index

  replace_any_args_with_splat_of_anything(any_args_index, actual_args.count)
end

Private Instance Methods

ensure_expected_args_valid!() click to toggle source
# File lib/rspec/mocks/argument_list_matcher.rb, line 83
def ensure_expected_args_valid!
  if expected_args.count { |a| ArgumentMatchers::AnyArgsMatcher::INSTANCE == a } > 1
    raise ArgumentError, "`any_args` can only be passed to " \
          "`with` once but you have passed it multiple times."
  elsif expected_args.count > 1 && expected_args.any? { |a| ArgumentMatchers::NoArgsMatcher::INSTANCE == a }
    raise ArgumentError, "`no_args` can only be passed as a " \
          "singleton argument to `with` (i.e. `with(no_args)`), " \
          "but you have passed additional arguments."
  end
end
replace_any_args_with_splat_of_anything(before_count, actual_args_count) click to toggle source
# File lib/rspec/mocks/argument_list_matcher.rb, line 75
def replace_any_args_with_splat_of_anything(before_count, actual_args_count)
  any_args_count  = actual_args_count   - expected_args.count + 1
  after_count     = expected_args.count - before_count        - 1

  any_args = 1.upto(any_args_count).map { ArgumentMatchers::AnyArgMatcher::INSTANCE }
  expected_args.first(before_count) + any_args + expected_args.last(after_count)
end