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module ActiveSupport::Testing::NotificationAssertions

Public instance methods

assert_no_notifications(pattern = nil, &block)

Assert no notifications were emitted for a given pattern.

You can assert no notifications were emitted by passing a pattern, which accepts either a string or regexp, and a block. While the block is executed, if no matching notifications are emitted, the assertion will pass.

assert_no_notifications("post.submitted") do
  post.destroy # => emits non-matching notification
end
Source code GitHub 
# File activesupport/lib/active_support/testing/notification_assertions.rb, line 52
def assert_no_notifications(pattern = nil, &block)
  notifications = capture_notifications(pattern, &block)
  error_message = if pattern
    "Expected no notifications for #{pattern} but found #{notifications.size}"
  else
    "Expected no notifications but found #{notifications.size}"
  end
  assert_empty(notifications, error_message)
end

assert_notification(pattern, payload = nil, &block)

Assert a notification was emitted with a given pattern and optional payload.

You can assert that a notification was emitted by passing a pattern, which accepts either a string or regexp, an optional payload, and a block. While the block is executed, if a matching notification is emitted, the assertion will pass.

assert_notification("post.submitted", title: "Cool Post") do
  post.submit(title: "Cool Post") # => emits matching notification
end
Source code GitHub 
# File activesupport/lib/active_support/testing/notification_assertions.rb, line 16
def assert_notification(pattern, payload = nil, &block)
  notifications = capture_notifications(pattern, &block)
  assert_not_empty(notifications, "No #{pattern} notifications were found")

  return if payload.nil?

  notification = notifications.find { |notification| notification.payload == payload }
  assert_not_nil(notification, "No #{pattern} notification with payload #{payload} was found")
end

assert_notifications_count(pattern, count, &block)

Assert the number of notifications emitted with a given pattern.

You can assert the number of notifications emitted by passing a pattern, which accepts either a string or regexp, a count, and a block. While the block is executed, the number of matching notifications emitted will be counted. After the block’s execution completes, the assertion will pass if the count matches.

assert_notifications_count("post.submitted", 1) do
  post.submit(title: "Cool Post") # => emits matching notification
end
Source code GitHub 
# File activesupport/lib/active_support/testing/notification_assertions.rb, line 37
def assert_notifications_count(pattern, count, &block)
  actual_count = capture_notifications(pattern, &block).count
  assert_equal(count, actual_count, "Expected #{count} instead of #{actual_count} notifications for #{pattern}")
end

capture_notifications(pattern = nil, &block)

Capture emitted notifications, optionally filtered by a pattern.

You can capture emitted notifications, optionally filtered by a pattern, which accepts either a string or regexp, and a block.

notifications = capture_notifications("post.submitted") do
  post.submit(title: "Cool Post") # => emits matching notification
end
Source code GitHub 
# File activesupport/lib/active_support/testing/notification_assertions.rb, line 71
def capture_notifications(pattern = nil, &block)
  notifications = []
  ActiveSupport::Notifications.subscribed(->(n) { notifications << n }, pattern, &block)
  notifications
end

Definition files