# File activesupport/lib/active_support/testing/deprecation.rb, line 31
def assert_deprecated(match = nil, deprecator = nil, &block)
  result, warnings = collect_deprecations(deprecator, &block)
  assert !warnings.empty?, "Expected a deprecation warning within the block but received none"
  if match
    match = Regexp.new(Regexp.escape(match)) unless match.is_a?(Regexp)
    assert warnings.any? { |w| match.match?(w) }, "No deprecation warning matched #{match}: #{warnings.join(', ')}"
  end
  result
end

Asserts that a matching deprecation warning was emitted by the given deprecator during the execution of the yielded block.

assert_deprecated(/foo/, CustomDeprecator) do
  CustomDeprecator.warn "foo should no longer be used"
end

The match object may be a Regexp, or String appearing in the message.

assert_deprecated('foo', CustomDeprecator) do
  CustomDeprecator.warn "foo should no longer be used"
end

If the match is omitted (or explicitly nil), any deprecation warning will match.

assert_deprecated(nil, CustomDeprecator) do
  CustomDeprecator.warn "foo should no longer be used"
end

If no deprecator is given, defaults to ActiveSupport::Deprecation.

assert_deprecated do
  ActiveSupport::Deprecation.warn "foo should no longer be used"
end

# File activesupport/lib/active_support/testing/deprecation.rb, line 56
def assert_not_deprecated(deprecator = nil, &block)
  result, deprecations = collect_deprecations(deprecator, &block)
  assert deprecations.empty?, "Expected no deprecation warning within the block but received #{deprecations.size}: \n  #{deprecations * "\n  "}"
  result
end

Asserts that no deprecation warnings are emitted by the given deprecator during the execution of the yielded block.

assert_not_deprecated(CustomDeprecator) do
  CustomDeprecator.warn "message" # fails assertion
end

If no deprecator is given, defaults to ActiveSupport::Deprecation.

assert_not_deprecated do
  ActiveSupport::Deprecation.warn "message" # fails assertion
end

assert_not_deprecated do
  CustomDeprecator.warn "message" # passes assertion
end

# File activesupport/lib/active_support/testing/deprecation.rb, line 75
def collect_deprecations(deprecator = nil)
  deprecator ||= ActiveSupport::Deprecation
  old_behavior = deprecator.behavior
  deprecations = []
  deprecator.behavior = Proc.new do |message, callstack|
    deprecations << message
  end
  result = yield
  [result, deprecations]
ensure
  deprecator.behavior = old_behavior
end

Returns an array of all the deprecation warnings emitted by the given deprecator during the execution of the yielded block.

collect_deprecations(CustomDeprecator) do
  CustomDeprecator.warn "message"
end # => ["message"]

If no deprecator is given, defaults to ActiveSupport::Deprecation.

collect_deprecations do
  CustomDeprecator.warn "custom message"
  ActiveSupport::Deprecation.warn "message"
end # => ["message"]