class RuboCop::Cop::RSpec::ExpectChange

Checks for consistent style of change matcher.

Enforces either passing object and attribute as arguments to the matcher or passing a block that reads the attribute value.

This cop can be configured using the ‘EnforcedStyle` option.

@example ‘EnforcedStyle: method_call` (default)

# bad
expect { run }.to change { Foo.bar }
expect { run }.to change { foo.baz }

# good
expect { run }.to change(Foo, :bar)
expect { run }.to change(foo, :baz)
# also good when there are arguments or chained method calls
expect { run }.to change { Foo.bar(:count) }
expect { run }.to change { user.reload.name }

@example ‘EnforcedStyle: block`

# bad
expect { run }.to change(Foo, :bar)

# good
expect { run }.to change { Foo.bar }

Constants

MSG_BLOCK
MSG_CALL
RESTRICT_ON_SEND

Public Instance Methods

on_block(node) click to toggle source
# File lib/rubocop/cop/rspec/expect_change.rb, line 72
def on_block(node) # rubocop:disable InternalAffairs/NumblockHandler
  return unless style == :method_call

  expect_change_with_block(node) do |receiver, message|
    msg = format(MSG_BLOCK, obj: receiver.source, attr: message)
    add_offense(node, message: msg) do |corrector|
      replacement = "change(#{receiver.source}, :#{message})"
      corrector.replace(node, replacement)
    end
  end
end
on_send(node) click to toggle source
# File lib/rubocop/cop/rspec/expect_change.rb, line 60
def on_send(node)
  return unless style == :block

  expect_change_with_arguments(node) do |receiver, message|
    msg = format(MSG_CALL, obj: receiver.source, attr: message)
    add_offense(node, message: msg) do |corrector|
      replacement = "change { #{receiver.source}.#{message} }"
      corrector.replace(node, replacement)
    end
  end
end