class RuboCop::Cop::RSpec::MultipleExpectations

Checks if examples contain too many `expect` calls.

@see betterspecs.org/#single Single expectation test

This cop is configurable using the `Max` option and works with `–auto-gen-config`.

@example

# bad
describe UserCreator do
  it 'builds a user' do
    expect(user.name).to eq("John")
    expect(user.age).to eq(22)
  end
end

# good
describe UserCreator do
  it 'sets the users name' do
    expect(user.name).to eq("John")
  end

  it 'sets the users age'
    expect(user.age).to eq(22)
  end
end

@example configuration

# .rubocop.yml
RSpec/MultipleExpectations:
  Max: 2

# not flagged by rubocop
describe UserCreator do
  it 'builds a user' do
    expect(user.name).to eq("John")
    expect(user.age).to eq(22)
  end
end

Constants

MSG

Public Instance Methods

on_block(node) click to toggle source
# File lib/rubocop/cop/rspec/multiple_expectations.rb, line 62
def on_block(node)
  return unless example?(node)

  return if example_with_aggregated_failures?(node)

  expectations_count = to_enum(:find_expectation, node).count

  return if expectations_count <= max_expectations

  self.max = expectations_count

  flag_example(node, expectation_count: expectations_count)
end

Private Instance Methods

example_with_aggregated_failures?(node) click to toggle source
# File lib/rubocop/cop/rspec/multiple_expectations.rb, line 78
def example_with_aggregated_failures?(node)
  example = node.children.first

  with_aggregated_failures?(example) &&
    !disabled_aggregated_failures?(example)
end
find_expectation(node) { || ... } click to toggle source
# File lib/rubocop/cop/rspec/multiple_expectations.rb, line 85
def find_expectation(node, &block)
  yield if expect?(node) || aggregate_failures?(node)

  # do not search inside of aggregate_failures block
  return if aggregate_failures?(node)

  node.each_child_node do |child|
    find_expectation(child, &block)
  end
end
flag_example(node, expectation_count:) click to toggle source
# File lib/rubocop/cop/rspec/multiple_expectations.rb, line 96
def flag_example(node, expectation_count:)
  method, = *node

  add_offense(
    method,
    location: :expression,
    message: format(
      MSG,
      total: expectation_count,
      max: max_expectations
    )
  )
end
max_expectations() click to toggle source
# File lib/rubocop/cop/rspec/multiple_expectations.rb, line 110
def max_expectations
  Integer(cop_config.fetch('Max', 1))
end