class RuboCop::Cop::RSpec::ExpectActual

Checks for `expect(…)` calls containing literal values.

@example

# bad
expect(5).to eq(price)
expect(/foo/).to eq(pattern)
expect("John").to eq(name)

# good
expect(price).to eq(5)
expect(pattern).to eq(/foo/)
expect(name).to eq("John")

Constants

COMPLEX_LITERALS
MSG
SIMPLE_LITERALS
SUPPORTED_MATCHERS

Public Instance Methods

on_send(node) click to toggle source
# File lib/rubocop/cop/rspec/expect_actual.rb, line 60
def on_send(node)
  expect_literal(node) do |actual, matcher, expected|
    add_offense(actual.source_range) do |corrector|
      next unless SUPPORTED_MATCHERS.include?(matcher)
      next if literal?(expected)

      swap(corrector, actual, expected)
    end
  end
end

Private Instance Methods

complex_literal?(node) click to toggle source
# File lib/rubocop/cop/rspec/expect_actual.rb, line 83
def complex_literal?(node)
  COMPLEX_LITERALS.include?(node.type) &&
    node.each_child_node.all?(&method(:literal?))
end
literal?(node) click to toggle source

This is not implement using a NodePattern because it seems to not be able to match against an explicit (nil) sexp

# File lib/rubocop/cop/rspec/expect_actual.rb, line 75
def literal?(node)
  node && (simple_literal?(node) || complex_literal?(node))
end
simple_literal?(node) click to toggle source
# File lib/rubocop/cop/rspec/expect_actual.rb, line 79
def simple_literal?(node)
  SIMPLE_LITERALS.include?(node.type)
end
swap(corrector, actual, expected) click to toggle source
# File lib/rubocop/cop/rspec/expect_actual.rb, line 88
def swap(corrector, actual, expected)
  corrector.replace(actual.source_range, expected.source)
  corrector.replace(expected.source_range, actual.source)
end