CHANGELOG.md

• Adds a new deprecation behaviour that aborts the application. Throwing this line into +config/environments/development.rb+

  ActiveSupport::Deprecation.behavior = :abort
  

  will cause the application to raise an +ActiveSupport::DeprecationException+ on deprecations.

  Use this for aggressive deprecation cleanups.

  Xavier Noria

• Remove 'cow' => 'kine' irregular inflection from default inflections.

  Andrew White

• Add DateTime#to_s(:iso8601) and Date#to_s(:iso8601) for consistency.

  Andrew White

• Add Time#to_s(:iso8601) for easy conversion of times to the iso8601 format for easy Javascript date parsing.

  DHH

• Improve ActiveSupport::Cache::MemoryStore cache size calculation. The memory used by a key/entry pair is calculated via #cached_size:

  def cached_size(key, entry)
    key.to_s.bytesize + entry.size + PER_ENTRY_OVERHEAD
  end
  

  The value of PER_ENTRY_OVERHEAD is 240 bytes based on an empirical estimation for 64-bit MRI on 1.9.3 and 2.0. GH#11512

  Simeon Simeonov

• Only raise Module::DelegationError if it's the source of the exception.

  Fixes #10559

  Andrew White

• Make Time.at_with_coercion retain the second fraction and return local time.

  Fixes #11350

  Neer Friedman, Andrew White

• Make HashWithIndifferentAccess#select always return the hash, even when Hash#select! returns nil, to allow further chaining.

  Marc Schütz

• Remove deprecated String#encoding_aware? core extensions (core_ext/string/encoding).

  Arun Agrawal

• Remove deprecated Module#local_constant_names in favor of Module#local_constants.

  Arun Agrawal

• Remove deprecated DateTime.local_offset in favor of DateTime.civil_from_fromat.

  Arun Agrawal

• Remove deprecated Logger core extensions (core_ext/logger.rb).

  Carlos Antonio da Silva

• Remove deprecated Time#time_with_datetime_fallback, Time#utc_time and Time#local_time in favor of Time#utc and Time#local.

  Vipul A M

• Remove deprecated Hash#diff with no replacement.

  If you're using it to compare hashes for the purpose of testing, please use MiniTest's assert_equal instead.

  Carlos Antonio da Silva

• Remove deprecated Date#to_time_in_current_zone in favor of Date#in_time_zone.

  Vipul A M

• Remove deprecated Proc#bind with no replacement.

  Carlos Antonio da Silva

• Remove deprecated Array#uniq_by and Array#uniq_by!, use native Array#uniq and Array#uniq! instead.

  Carlos Antonio da Silva

• Remove deprecated ActiveSupport::BasicObject, use ActiveSupport::ProxyObject instead.

  Carlos Antonio da Silva

• Remove deprecated BufferedLogger.

  Yves Senn

• Remove deprecated assert_present and assert_blank methods.

  Yves Senn

• Fix return value from BacktraceCleaner#noise when the cleaner is configured with multiple silencers.

  Fixes #11030

  Mark J. Titorenko

• HashWithIndifferentAccess#select now returns a HashWithIndifferentAccess instance instead of a Hash instance.

  Fixes #10723

  Albert Llop

• Add DateTime#usec and DateTime#nsec so that ActiveSupport::TimeWithZone keeps sub-second resolution when wrapping a DateTime value.

  Fixes #10855

  Andrew White

• Fix ActiveSupport::Dependencies::Loadable#load_dependency calling #blame_file! on Exceptions that do not have the Blamable mixin

  Andrew Kreiling

• Override Time.at to support the passing of Time-like values when called with a single argument.

  Andrew White

• Prevent side effects to hashes inside arrays when Hash#with_indifferent_access is called.

  Fixes #10526

  Yves Senn

• Raise an error when multiple included blocks are defined for a Concern. The old behavior would silently discard previously defined blocks, running only the last one.

  Mike Dillon

• Replace multi_json with json.

  Since Rails requires Ruby 1.9 and since Ruby 1.9 includes json in the standard library, multi_json is no longer necessary.

  Erik Michaels-Ober

• Added escaping of U+2028 and U+2029 inside the json encoder. These characters are legal in JSON but break the Javascript interpreter. After escaping them, the JSON is still legal and can be parsed by Javascript.

  Mario Caropreso + Viktor Kelemen + zackham

• Fix skipping object callbacks using metadata fetched via callback chain inspection methods (_*_callbacks)

  Sean Walbran

• Add a fetch_multi method to the cache stores. The method provides an easy to use API for fetching multiple values from the cache.

  Example:

  # Calculating scores is expensive, so we only do it for posts
  # that have been updated. Cache keys are automatically extracted
  # from objects that define a #cache_key method.
  scores = Rails.cache.fetch_multi(*posts) do |post|
    calculate_score(post)
  end
  

  Daniel Schierbeck

Please check 4-0-stable for previous changes.