Start Rails 5.2 development

3 files changed, 7 insertions, 774 deletions

diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md
index 4488524c4e..30d580b9e3 100644
--- a/activerecord/CHANGELOG.md
+++ b/activerecord/CHANGELOG.md
@@ -1,771 +1 @@
-*   Remove comments from structure.sql when using postgresql adapter to avoid
-    version-specific parts of the file.
-
-    Fixes #28153.
-
-    *Ari Pollak*
-
-*   Add `:default` option to `belongs_to`.
-
-    Use it to specify that an association should be initialized with a particular
-    record before validation. For example:
-
-        # Before
-        belongs_to :account
-        before_validation -> { self.account ||= Current.account }
-
-        # After
-        belongs_to :account, default: -> { Current.account }
-
-    *George Claghorn*
-
-*   Deprecate `Migrator.schema_migrations_table_name`.
-
-    *Ryuta Kamizono*
-
-*   Fix select with block doesn't return newly built records in has_many association.
-
-    Fixes #28348.
-
-    *Ryuta Kamizono*
-
-*   Check whether `Rails.application` defined before calling it
-
-    In #27674 we changed the migration generator to generate migrations at the
-    path defined in `Rails.application.config.paths` however the code checked
-    for the presence of the `Rails` constant but not the `Rails.application`
-    method which caused problems when using Active Record and generators outside
-    of the context of a Rails application.
-
-    Fixes #28325.
-
-    *Andrew White*
-
-*   Fix `deserialize` with JSON array.
-
-    Fixes #28285.
-
-    *Ryuta Kamizono*
-
-*   Fix `rake db:schema:load` with subdirectories.
-
-    *Ryuta Kamizono*
-
-*   Fix `rake db:migrate:status` with subdirectories.
-
-    *Ryuta Kamizono*
-
-*   Don't share options between reference id and type columns
-
-    When using a polymorphic reference column in a migration, sharing options
-    between the two columns doesn't make sense since they are different types.
-    The `reference_id` column is usually an integer and the `reference_type`
-    column a string so options like `unsigned: true` will result in an invalid
-    table definition.
-
-    *Ryuta Kamizono*
-
-*   Use `max_identifier_length` for `index_name_length` in PostgreSQL adapter.
-
-    *Ryuta Kamizono*
-
-*   Deprecate `supports_migrations?` on connection adapters.
-
-    *Ryuta Kamizono*
-
-*   Fix regression of #1969 with SELECT aliases in HAVING clause.
-
-    *Eugene Kenny*
-
-*   Deprecate using `#quoted_id` in quoting.
-
-    *Ryuta Kamizono*
-
-*   Fix `wait_timeout` to configurable for mysql2 adapter.
-
-    Fixes #26556.
-
-    *Ryuta Kamizono*
-
-
-## Rails 5.1.0.beta1 (February 23, 2017) ##
-
-*   Correctly dump native timestamp types for MySQL.
-
-    The native timestamp type in MySQL is different from datetime type.
-    Internal representation of the timestamp type is UNIX time, This means
-    that timestamp columns are affected by time zone.
-
-        > SET time_zone = '+00:00';
-        Query OK, 0 rows affected (0.00 sec)
-
-        > INSERT INTO time_with_zone(ts,dt) VALUES (NOW(),NOW());
-        Query OK, 1 row affected (0.02 sec)
-
-        > SELECT * FROM time_with_zone;
-        +---------------------+---------------------+
-        | ts                  | dt                  |
-        +---------------------+---------------------+
-        | 2016-02-07 22:11:44 | 2016-02-07 22:11:44 |
-        +---------------------+---------------------+
-        1 row in set (0.00 sec)
-
-        > SET time_zone = '-08:00';
-        Query OK, 0 rows affected (0.00 sec)
-
-        > SELECT * FROM time_with_zone;
-        +---------------------+---------------------+
-        | ts                  | dt                  |
-        +---------------------+---------------------+
-        | 2016-02-07 14:11:44 | 2016-02-07 22:11:44 |
-        +---------------------+---------------------+
-        1 row in set (0.00 sec)
-
-    *Ryuta Kamizono*
-
-*   All integer-like PKs are autoincrement unless they have an explicit default.
-
-    *Matthew Draper*
-
-*   Omit redundant `using: :btree` for schema dumping.
-
-    *Ryuta Kamizono*
-
-*   Deprecate passing `default` to `index_name_exists?`.
-
-    *Ryuta Kamizono*
-
-*   PostgreSQL: schema dumping support for interval and OID columns.
-
-    *Ryuta Kamizono*
-
-*   Deprecate `supports_primary_key?` on connection adapters since it's
-    been long unused and unsupported.
-
-    *Ryuta Kamizono*
-
-*   Make `table_name=` reset current statement cache,
-    so queries are not run against the previous table name.
-
-    *namusyaka*
-
-*   Allow `ActiveRecord::Base#as_json` to be passed a frozen Hash.
-
-    *Isaac Betesh*
-
-*   Fix inspection behavior when the :id column is not primary key.
-
-    *namusyaka*
-
-*   Deprecate locking records with unpersisted changes.
-
-    *Marc Schütz*
-
-*   Remove deprecated behavior that halts callbacks when the return is false.
-
-    *Rafael Mendonça França*
-
-*   Deprecate `ColumnDumper#migration_keys`.
-
-    *Ryuta Kamizono*
-
-*   Fix `association_primary_key_type` for reflections with symbol primary key.
-
-    Fixes #27864.
-
-    *Daniel Colson*
-
-*   Virtual/generated column support for MySQL 5.7.5+ and MariaDB 5.2.0+.
-
-    MySQL generated columns: https://dev.mysql.com/doc/refman/5.7/en/create-table-generated-columns.html
-    MariaDB virtual columns: https://mariadb.com/kb/en/mariadb/virtual-computed-columns/
-
-    Declare virtual columns with `t.virtual name, type: …, as: "expression"`.
-    Pass `stored: true` to persist the generated value (false by default).
-
-    Example:
-
-        create_table :generated_columns do |t|
-          t.string  :name
-          t.virtual :upper_name,  type: :string,  as: "UPPER(name)"
-          t.virtual :name_length, type: :integer, as: "LENGTH(name)", stored: true
-          t.index :name_length  # May be indexed, too!
-        end
-
-    *Ryuta Kamizono*
-
-*   Deprecate `initialize_schema_migrations_table` and `initialize_internal_metadata_table`.
-
-    *Ryuta Kamizono*
-
-*   Support foreign key creation for SQLite3.
-
-    *Ryuta Kamizono*
-
-*   Place generated migrations into the path set by `config.paths["db/migrate"]`.
-
-    *Kevin Glowacz*
-
-*   Raise `ActiveRecord::InvalidForeignKey` when a foreign key constraint fails on SQLite3.
-
-    *Ryuta Kamizono*
-
-*   Add the touch option to `#increment!` and `#decrement!`.
-
-    *Hiroaki Izu*
-
-*   Deprecate passing a class to the `class_name` because it eagerloads more classes than
-    necessary and potentially creates circular dependencies.
-
-    *Kir Shatrov*
-
-*   Raise error when has_many through is defined before through association.
-
-    Fixes #26834.
-
-    *Chris Holmes*
-
-*   Deprecate passing `name` to `indexes`.
-
-    *Ryuta Kamizono*
-
-*   Remove deprecated tasks: `db:test:clone`, `db:test:clone_schema`, `db:test:clone_structure`.
-
-    *Rafel Mendonça França*
-
-*   Compare deserialized values for `PostgreSQL::OID::Hstore` types when
-    calling `ActiveRecord::Dirty#changed_in_place?`.
-
-    Fixes #27502.
-
-    *Jon Moss*
-
-*   Raise `ArgumentError` when passing an `ActiveRecord::Base` instance to `.find`,
-    `.exists?` and `.update`.
-
-    *Rafael Mendonça França*
-
-*   Respect precision option for arrays of timestamps.
-
-    Fixes #27514.
-
-    *Sean Griffin*
-
-*   Optimize slow model instantiation when using STI and `store_full_sti_class = false` option.
-
-    *Konstantin Lazarev*
-
-*   Add `touch` option to counter cache modifying methods.
-
-    Works when updating, resetting, incrementing and decrementing counters:
-
-        # Touches `updated_at`/`updated_on`.
-        Topic.increment_counter(:messages_count, 1, touch: true)
-        Topic.decrement_counter(:messages_count, 1, touch: true)
-
-        # Touches `last_discussed_at`.
-        Topic.reset_counters(18, :messages, touch: :last_discussed_at)
-
-        # Touches `updated_at` and `last_discussed_at`.
-        Topic.update_counters(18, messages_count: 5, touch: %i( updated_at last_discussed_at ))
-
-    Fixes #26724.
-
-    *Jarred Trost*
-
-*   Remove deprecated `#uniq`, `#uniq!`, and `#uniq_value`.
-
-    *Ryuta Kamizono*
-
-*   Remove deprecated `#insert_sql`, `#update_sql`, and `#delete_sql`.
-
-    *Ryuta Kamizono*
-
-*   Remove deprecated `#use_transactional_fixtures` configuration.
-
-    *Rafael Mendonça França*
-
-*   Remove deprecated `#raise_in_transactional_callbacks` configuration.
-
-    *Rafael Mendonça França*
-
-*   Remove deprecated `#load_schema_for`.
-
-    *Rafael Mendonça França*
-
-*   Remove deprecated conditions parameter from `#destroy_all` and `#delete_all`.
-
-    *Rafael Mendonça França*
-
-*   Remove deprecated support to passing arguments to `#select` when a block is provided.
-
-    *Rafael Mendonça França*
-
-*   Remove deprecated support to query using commas on LIMIT.
-
-    *Rafael Mendonça França*
-
-*   Remove deprecated support to passing a class as a value in a query.
-
-    *Rafael Mendonça França*
-
-*   Raise `ActiveRecord::IrreversibleOrderError` when using `last` with an irreversible
-    order.
-
-    *Rafael Mendonça França*
-
-*   Raise when a `has_many :through` association has an ambiguous reflection name.
-
-    *Rafael Mendonça França*
-
-*   Raise when `ActiveRecord::Migration` is inherited from directly.
-
-    *Rafael Mendonça França*
-
-*   Remove deprecated `original_exception` argument in `ActiveRecord::StatementInvalid#initialize`
-    and `ActiveRecord::StatementInvalid#original_exception`.
-
-    *Rafael Mendonça França*
-
-*   `#tables` and `#table_exists?` return only tables and not views.
-
-    All the deprecations on those methods were removed.
-
-    *Rafael Mendonça França*
-
-*   Remove deprecated `name` argument from `#tables`.
-
-    *Rafael Mendonça França*
-
-*   Remove deprecated support to passing a column to `#quote`.
-
-    *Rafael Mendonça França*
-
-*   Set `:time` as a timezone aware type and remove deprecation when
-    `config.active_record.time_zone_aware_types` is not explicitly set.
-
-    *Rafael Mendonça França*
-
-*   Remove deprecated force reload argument in singular and collection association readers.
-
-    *Rafael Mendonça França*
-
-*   Remove deprecated `activerecord.errors.messages.restrict_dependent_destroy.one` and
-    `activerecord.errors.messages.restrict_dependent_destroy.many` i18n scopes.
-
-    *Rafael Mendonça França*
-
-*   Allow passing extra flags to `db:structure:load` and `db:structure:dump`
-
-    Introduces `ActiveRecord::Tasks::DatabaseTasks.structure_(load|dump)_flags` to customize the
-    eventual commands run against the database, e.g. mysqldump/pg_dump.
-
-    *Kir Shatrov*
-
-*   Notifications see frozen SQL string.
-
-    Fixes #23774.
-
-    *Richard Monette*
-
-*   RuntimeErrors are no longer translated to `ActiveRecord::StatementInvalid`.
-
-    *Richard Monette*
-
-*   Change the schema cache format to use YAML instead of Marshal.
-
-    *Kir Shatrov*
-
-*   Support index length and order options using both string and symbol
-    column names.
-
-    Fixes #27243.
-
-    *Ryuta Kamizono*
-
-*   Raise `ActiveRecord::RangeError` when values that executed are out of range.
-
-    *Ryuta Kamizono*
-
-*   Raise `ActiveRecord::NotNullViolation` when a record cannot be inserted
-    or updated because it would violate a not null constraint.
-
-    *Ryuta Kamizono*
-
-*   Emulate db trigger behaviour for after_commit :destroy, :update.
-
-    Race conditions can occur when an ActiveRecord is destroyed
-    twice or destroyed and updated. The callbacks should only be
-    triggered once, similar to a SQL database trigger.
-
-    *Stefan Budeanu*
-
-*   Moved `DecimalWithoutScale`, `Text`, and `UnsignedInteger` from Active Model to Active Record.
-
-    *Iain Beeston*
-
-*   Fix `write_attribute` method to check whether an attribute is aliased or not, and
-    use the aliased attribute name if needed.
-
-    *Prathamesh Sonpatki*
-
-*   Fix `read_attribute` method to check whether an attribute is aliased or not, and
-    use the aliased attribute name if needed.
-
-    Fixes #26417.
-
-    *Prathamesh Sonpatki*
-
-*   PostgreSQL & MySQL: Use big integer as primary key type for new tables.
-
-    *Jon McCartie*, *Pavel Pravosud*
-
-*   Change the type argument of `ActiveRecord::Base#attribute` to be optional.
-    The default is now `ActiveRecord::Type::Value.new`, which provides no type
-    casting behavior.
-
-    *Sean Griffin*
-
-*   Don't treat unsigned integers with zerofill as signed.
-
-    Fixes #27125.
-
-    *Ryuta Kamizono*
-
-*   Fix the uniqueness validation scope with a polymorphic association.
-
-    *Sergey Alekseev*
-
-*   Raise `ActiveRecord::RecordNotFound` from collection `*_ids` setters
-    for unknown IDs with a better error message.
-
-    Changes the collection `*_ids` setters to cast provided IDs the data
-    type of the primary key set in the association, not the model
-    primary key.
-
-    *Dominic Cleal*
-
-*   For PostgreSQL >= 9.4 use `pgcrypto`'s `gen_random_uuid()` instead of
-    `uuid-ossp`'s UUID generation function.
-
-    *Yuji Yaginuma*, *Yaw Boakye*
-
-*   Introduce `Model#reload_<association>` to bring back the behavior
-    of `Article.category(true)` where `category` is a singular
-    association.
-
-    The force reloading of the association reader was deprecated
-    in #20888. Unfortunately the suggested alternative of
-    `article.reload.category` does not expose the same behavior.
-
-    This patch adds a reader method with the prefix `reload_` for
-    singular associations. This method has the same semantics as
-    passing true to the association reader used to have.
-
-    *Yves Senn*
-
-*   Make sure eager loading `ActiveRecord::Associations` also loads
-    constants defined in `ActiveRecord::Associations::Preloader`.
-
-    *Yves Senn*
-
-*   Allow `ActionController::Parameters`-like objects to be passed as
-    values for Postgres HStore columns.
-
-    Fixes #26904.
-
-    *Jon Moss*
-
-*   Added `stat` method to `ActiveRecord::ConnectionAdapters::ConnectionPool`.
-
-    Example:
-
-        ActiveRecord::Base.connection_pool.stat # =>
-        { size: 15, connections: 1, busy: 1, dead: 0, idle: 0, waiting: 0, checkout_timeout: 5 }
-
-    *Pavel Evstigneev*
-
-*   Avoid `unscope(:order)` when `limit_value` is presented for `count`
-    and `exists?`.
-
-    If `limit_value` is presented, records fetching order is very important
-    for performance. We should not unscope the order in the case.
-
-    *Ryuta Kamizono*
-
-*   Fix an Active Record `DateTime` field `NoMethodError` caused by incomplete
-    datetime.
-
-    Fixes #24195.
-
-    *Sen Zhang*
-
-*   Allow `slice` to take an array of methods(without the need for splatting).
-
-    *Cohen Carlisle*
-
-*   Improved partial writes with HABTM and has many through associations
-    to fire database query only if relation has been changed.
-
-    Fixes #19663.
-
-    *Mehmet Emin İNAÇ*
-
-*   Deprecate passing arguments and block at the same time to
-    `ActiveRecord::QueryMethods#select`.
-
-    *Prathamesh Sonpatki*
-
-*   Fixed: Optimistic locking does not work well with `null` in the database.
-
-    Fixes #26024.
-
-    *bogdanvlviv*
-
-*   Fixed support for case insensitive comparisons of `text` columns in
-    PostgreSQL.
-
-    *Edho Arief*
-
-*   Serialize JSON attribute value `nil` as SQL `NULL`, not JSON `null`.
-
-    *Trung Duc Tran*
-
-*   Return `true` from `update_attribute` when the value of the attribute
-    to be updated is unchanged.
-
-    Fixes #26593.
-
-    *Prathamesh Sonpatki*
-
-*   Always store errors details information with symbols.
-
-    When the association is autosaved we were storing the details with
-    string keys. This was creating inconsistency with other details that are
-    added using the `Errors#add` method. It was also inconsistent with the
-    `Errors#messages` storage.
-
-    To fix this inconsistency we are always storing with symbols. This will
-    cause a small breaking change because in those cases the details could
-    be accessed as strings keys but now it can not.
-
-    Fix #26499.
-
-    *Rafael Mendonça França*, *Marcus Vieira*
-
-*   Calling `touch` on a model using optimistic locking will now leave the model
-    in a non-dirty state with no attribute changes.
-
-    Fixes #26496.
-
-    *Jakob Skjerning*
-
-*   Using a mysql2 connection after it fails to reconnect will now have an error message
-    saying the connection is closed rather than an undefined method error message.
-
-    *Dylan Thacker-Smith*
-
-*   PostgreSQL array columns will now respect the encoding of strings contained
-    in the array.
-
-    Fixes #26326.
-
-    *Sean Griffin*
-
-*   Inverse association instances will now be set before `after_find` or
-    `after_initialize` callbacks are run.
-
-    Fixes #26320.
-
-    *Sean Griffin*
-
-*   Remove unnecessarily association load when a `belongs_to` association has already been
-    loaded then the foreign key is changed directly and the record saved.
-
-    *James Coleman*
-
-*   Remove standardized column types/arguments spaces in schema dump.
-
-    *Tim Petricola*
-
-*   Avoid loading records from database when they are already loaded using
-    the `pluck` method on a collection.
-
-    Fixes #25921.
-
-    *Ryuta Kamizono*
-
-*   Remove text default treated as an empty string in non-strict mode for
-    consistency with other types.
-
-    Strict mode controls how MySQL handles invalid or missing values in
-    data-change statements such as INSERT or UPDATE. If strict mode is not
-    in effect, MySQL inserts adjusted values for invalid or missing values
-    and produces warnings.
-
-        def test_mysql_not_null_defaults_non_strict
-          using_strict(false) do
-            with_mysql_not_null_table do |klass|
-              record = klass.new
-              assert_nil record.non_null_integer
-              assert_nil record.non_null_string
-              assert_nil record.non_null_text
-              assert_nil record.non_null_blob
-
-              record.save!
-              record.reload
-
-              assert_equal 0,  record.non_null_integer
-              assert_equal "", record.non_null_string
-              assert_equal "", record.non_null_text
-              assert_equal "", record.non_null_blob
-            end
-          end
-        end
-
-    https://dev.mysql.com/doc/refman/5.7/en/sql-mode.html#sql-mode-strict
-
-    *Ryuta Kamizono*
-
-*   SQLite3 migrations to add a column to an existing table can now be
-    successfully rolled back when the column was given and invalid column
-    type.
-
-    Fixes #26087.
-
-    *Travis O'Neill*
-
-*   Deprecate `sanitize_conditions`. Use `sanitize_sql` instead.
-
-    *Ryuta Kamizono*
-
-*   Doing count on relations that contain LEFT OUTER JOIN Arel node no longer
-    force a DISTINCT. This solves issues when using count after a left_joins.
-
-    *Maxime Handfield Lapointe*
-
-*   RecordNotFound raised by association.find exposes `id`, `primary_key` and
-    `model` methods to be consistent with RecordNotFound raised by Record.find.
-
-    *Michel Pigassou*
-
-*   Hashes can once again be passed to setters of `composed_of`, if all of the
-    mapping methods are methods implemented on `Hash`.
-
-    Fixes #25978.
-
-    *Sean Griffin*
-
-*   Fix the SELECT statement in `#table_comment` for MySQL.
-
-    *Takeshi Akima*
-
-*   Virtual attributes will no longer raise when read on models loaded from the
-    database.
-
-    *Sean Griffin*
-
-*   Support calling the method `merge` in `scope`'s lambda.
-
-    *Yasuhiro Sugino*
-
-*   Fixes multi-parameter attributes conversion with invalid params.
-
-    *Hiroyuki Ishii*
-
-*   Add newline between each migration in `structure.sql`.
-
-    Keeps schema migration inserts as a single commit, but allows for easier
-    git diffing.
-
-    Fixes #25504.
-
-    *Grey Baker*, *Norberto Lopes*
-
-*   The flag `error_on_ignored_order_or_limit` has been deprecated in favor of
-    the current `error_on_ignored_order`.
-
-    *Xavier Noria*
-
-*   Batch processing methods support `limit`:
-
-        Post.limit(10_000).find_each do |post|
-          # ...
-        end
-
-    It also works in `find_in_batches` and `in_batches`.
-
-    *Xavier Noria*
-
-*   Using `group` with an attribute that has a custom type will properly cast
-    the hash keys after calling a calculation method like `count`.
-
-    Fixes #25595.
-
-    *Sean Griffin*
-
-*   Fix the generated `#to_param` method to use `omission: ''` so that
-    the resulting output is actually up to 20 characters, not
-    effectively 17 to leave room for the default "...".
-    Also call `#parameterize` before `#truncate` and make the
-    `separator: /-/` to maximize the information included in the
-    output.
-
-    Fixes #23635.
-
-    *Rob Biedenharn*
-
-*   Ensure concurrent invocations of the connection reaper cannot allocate the
-    same connection to two threads.
-
-    Fixes #25585.
-
-    *Matthew Draper*
-
-*   Inspecting an object with an associated array of over 10 elements no longer
-    truncates the array, preventing `inspect` from looping infinitely in some
-    cases.
-
-    *Kevin McPhillips*
-
-*   Removed the unused methods `ActiveRecord::Base.connection_id` and
-    `ActiveRecord::Base.connection_id=`.
-
-    *Sean Griffin*
-
-*   Ensure hashes can be assigned to attributes created using `composed_of`.
-
-    Fixes #25210.
-
-    *Sean Griffin*
-
-*   Fix logging edge case where if an attribute was of the binary type and
-    was provided as a Hash.
-
-    *Jon Moss*
-
-*   Handle JSON deserialization correctly if the column default from database
-    adapter returns `''` instead of `nil`.
-
-    *Johannes Opper*
-
-*   Introduce new Active Record transaction error classes for catching
-    transaction serialization failures or deadlocks.
-
-    *Erol Fornoles*
-
-*   PostgreSQL: Fix `db:structure:load` silent failure on SQL error.
-
-    The command line flag `-v ON_ERROR_STOP=1` should be used
-    when invoking `psql` to make sure errors are not suppressed.
-
-    Example:
-
-        psql -v ON_ERROR_STOP=1 -q -f awesome-file.sql my-app-db
-
-    Fixes #23818.
-
-    *Ralin Chimev*
-
-
-Please check [5-0-stable](https://github.com/rails/rails/blob/5-0-stable/activerecord/CHANGELOG.md) for previous changes.
+Please check [5-1-stable](https://github.com/rails/rails/blob/5-1-stable/activerecord/CHANGELOG.md) for previous changes.
diff --git a/activerecord/lib/active_record/gem_version.rb b/activerecord/lib/active_record/gem_version.rb
index 174f716152..1a937dbcf7 100644
--- a/activerecord/lib/active_record/gem_version.rb
+++ b/activerecord/lib/active_record/gem_version.rb
@@ -6,9 +6,9 @@ module ActiveRecord
 
   module VERSION
     MAJOR = 5
-    MINOR = 1
+    MINOR = 2
     TINY  = 0
-    PRE   = "beta1"
+    PRE   = "alpha"
 
     STRING = [MAJOR, MINOR, TINY, PRE].compact.join(".")
   end
diff --git a/activerecord/lib/active_record/migration/compatibility.rb b/activerecord/lib/active_record/migration/compatibility.rb
index 85032ce470..188dd0acef 100644
--- a/activerecord/lib/active_record/migration/compatibility.rb
+++ b/activerecord/lib/active_record/migration/compatibility.rb
@@ -11,7 +11,10 @@ module ActiveRecord
         const_get(name)
       end
 
-      V5_1 = Current
+      V5_2 = Current
+
+      class V5_1 < V5_2
+      end
 
       class V5_0 < V5_1
         module TableDefinition