Merge pull request #31727 from...

Merge pull request #31727 from eileencodes/refactor-migration-classes-to-allow-for-migrations_paths-on-conn

Refactor migration to move migrations paths to connection

activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb

@@ -1049,8 +1049,8 @@ def assume_migrated_upto_version(version, migrations_paths)
         sm_table = quote_table_name(ActiveRecord::SchemaMigration.table_name)
 
         migrated = ActiveRecord::SchemaMigration.all_versions.map(&:to_i)
-        versions = ActiveRecord::Migrator.migration_files(migrations_paths).map do |file|
-          ActiveRecord::Migrator.parse_migration_filename(file).first.to_i
+        versions = migration_context.migration_files.map do |file|
+          migration_context.parse_migration_filename(file).first.to_i
         end
 
         unless migrated.include?(version)

activerecord/lib/active_record/connection_adapters/abstract_adapter.rb

@@ -119,6 +119,14 @@ def initialize(connection, logger = nil, config = {}) # :nodoc:
         end
       end
 
+      def migrations_paths
+        @config[:migrations_paths] || Migrator.migrations_paths
+      end
+
+      def migration_context
+        MigrationContext.new(migrations_paths)
+      end
+
       class Version
         include Comparable
 

activerecord/lib/active_record/connection_adapters/schema_cache.rb

@@ -28,7 +28,7 @@ def encode_with(coder)
         coder["columns_hash"] = @columns_hash
         coder["primary_keys"] = @primary_keys
         coder["data_sources"] = @data_sources
-        coder["version"] = ActiveRecord::Migrator.current_version
+        coder["version"] = connection.migration_context.current_version
       end
 
       def init_with(coder)
@@ -100,7 +100,7 @@ def clear_data_source_cache!(name)
 
       def marshal_dump
         # if we get current version during initialization, it happens stack over flow.
-        @version = ActiveRecord::Migrator.current_version
+        @version = connection.migration_context.current_version
         [@version, @columns, @columns_hash, @primary_keys, @data_sources]
       end
 

activerecord/lib/active_record/migration.rb

@@ -3,6 +3,7 @@
 require "set"
 require "zlib"
 require "active_support/core_ext/module/attribute_accessors"
+require "active_record/tasks/database_tasks"
 
 module ActiveRecord
   class MigrationError < ActiveRecordError#:nodoc:
@@ -550,7 +551,7 @@ def initialize(app)
       end
 
       def call(env)
-        mtime = ActiveRecord::Migrator.last_migration.mtime.to_i
+        mtime = ActiveRecord::Base.connection.migration_context.last_migration.mtime.to_i
         if @last_check < mtime
           ActiveRecord::Migration.check_pending!(connection)
           @last_check = mtime
@@ -575,11 +576,11 @@ def nearest_delegate # :nodoc:
 
       # Raises <tt>ActiveRecord::PendingMigrationError</tt> error if any migrations are pending.
       def check_pending!(connection = Base.connection)
-        raise ActiveRecord::PendingMigrationError if ActiveRecord::Migrator.needs_migration?(connection)
+        raise ActiveRecord::PendingMigrationError if connection.migration_context.needs_migration?
       end
 
       def load_schema_if_pending!
-        if ActiveRecord::Migrator.needs_migration? || !ActiveRecord::Migrator.any_migrations?
+        if Base.connection.migration_context.needs_migration? || !Base.connection.migration_context.any_migrations?
           # Roundtrip to Rake to allow plugins to hook into database initialization.
           root = defined?(ENGINE_ROOT) ? ENGINE_ROOT : Rails.root
           FileUtils.cd(root) do
@@ -876,10 +877,10 @@ def copy(destination, sources, options = {})
 
       FileUtils.mkdir_p(destination) unless File.exist?(destination)
 
-      destination_migrations = ActiveRecord::Migrator.migrations(destination)
+      destination_migrations = ActiveRecord::MigrationContext.new(destination).migrations
       last = destination_migrations.last
       sources.each do |scope, path|
-        source_migrations = ActiveRecord::Migrator.migrations(path)
+        source_migrations = ActiveRecord::MigrationContext.new(path).migrations
 
         source_migrations.each do |migration|
           source = File.binread(migration.filename)
@@ -997,132 +998,147 @@ def mtime
     end
   end
 
-  class Migrator#:nodoc:
-    class << self
-      attr_writer :migrations_paths
-      alias :migrations_path= :migrations_paths=
-
-      def migrate(migrations_paths, target_version = nil, &block)
-        case
-        when target_version.nil?
-          up(migrations_paths, target_version, &block)
-        when current_version == 0 && target_version == 0
-          []
-        when current_version > target_version
-          down(migrations_paths, target_version, &block)
-        else
-          up(migrations_paths, target_version, &block)
-        end
-      end
+  class MigrationContext # :nodoc:
+    attr_reader :migrations_paths
 
-      def rollback(migrations_paths, steps = 1)
-        move(:down, migrations_paths, steps)
-      end
+    def initialize(migrations_paths)
+      @migrations_paths = migrations_paths
+    end
 
-      def forward(migrations_paths, steps = 1)
-        move(:up, migrations_paths, steps)
+    def migrate(target_version = nil, &block)
+      case
+      when target_version.nil?
+        up(target_version, &block)
+      when current_version == 0 && target_version == 0
+        []
+      when current_version > target_version
+        down(target_version, &block)
+      else
+        up(target_version, &block)
       end
+    end
 
-      def up(migrations_paths, target_version = nil)
-        migrations = migrations(migrations_paths)
-        migrations.select! { |m| yield m } if block_given?
+    def rollback(steps = 1)
+      move(:down, steps)
+    end
 
-        new(:up, migrations, target_version).migrate
+    def forward(steps = 1)
+      move(:up, steps)
+    end
+
+    def up(target_version = nil)
+      selected_migrations = if block_given?
+        migrations.select { |m| yield m }
+      else
+        migrations
       end
 
-      def down(migrations_paths, target_version = nil)
-        migrations = migrations(migrations_paths)
-        migrations.select! { |m| yield m } if block_given?
+      Migrator.new(:up, selected_migrations, target_version).migrate
+    end
 
-        new(:down, migrations, target_version).migrate
+    def down(target_version = nil)
+      selected_migrations = if block_given?
+        migrations.select { |m| yield m }
+      else
+        migrations
       end
 
-      def run(direction, migrations_paths, target_version)
-        new(direction, migrations(migrations_paths), target_version).run
-      end
+      Migrator.new(:down, migrations, target_version).migrate
+    end
 
-      def open(migrations_paths)
-        new(:up, migrations(migrations_paths), nil)
-      end
+    def run(direction, target_version)
+      Migrator.new(direction, migrations, target_version).run
+    end
 
-      def get_all_versions
-        if SchemaMigration.table_exists?
-          SchemaMigration.all_versions.map(&:to_i)
-        else
-          []
-        end
-      end
+    def open
+      Migrator.new(:up, migrations, nil)
+    end
 
-      def current_version(connection = nil)
-        get_all_versions.max || 0
-      rescue ActiveRecord::NoDatabaseError
+    def get_all_versions
+      if SchemaMigration.table_exists?
+        SchemaMigration.all_versions.map(&:to_i)
+      else
+        []
       end
+    end
 
-      def needs_migration?(connection = nil)
-        (migrations(migrations_paths).collect(&:version) - get_all_versions).size > 0
-      end
+    def current_version(connection = nil)
+      get_all_versions.max || 0
+    rescue ActiveRecord::NoDatabaseError
+    end
 
-      def any_migrations?
-        migrations(migrations_paths).any?
-      end
+    def needs_migration?
+      (migrations.collect(&:version) - get_all_versions).size > 0
+    end
 
-      def last_migration #:nodoc:
-        migrations(migrations_paths).last || NullMigration.new
-      end
+    def any_migrations?
+      migrations.any?
+    end
 
-      def migrations_paths
-        @migrations_paths ||= ["db/migrate"]
-        # just to not break things if someone uses: migrations_path = some_string
-        Array(@migrations_paths)
-      end
+    def last_migration #:nodoc:
+      migrations.last || NullMigration.new
+    end
 
-      def parse_migration_filename(filename) # :nodoc:
-        File.basename(filename).scan(Migration::MigrationFilenameRegexp).first
+    def parse_migration_filename(filename) # :nodoc:
+      File.basename(filename).scan(Migration::MigrationFilenameRegexp).first
+    end
+
+    def migrations
+      migrations = migration_files.map do |file|
+        version, name, scope = parse_migration_filename(file)
+        raise IllegalMigrationNameError.new(file) unless version
+        version = version.to_i
+        name = name.camelize
+
+        MigrationProxy.new(name, version, file, scope)
       end
 
-      def migrations(paths)
-        paths = Array(paths)
+      migrations.sort_by(&:version)
+    end
 
-        migrations = migration_files(paths).map do |file|
-          version, name, scope = parse_migration_filename(file)
-          raise IllegalMigrationNameError.new(file) unless version
-          version = version.to_i
-          name = name.camelize
+    def migrations_status
+      db_list = ActiveRecord::SchemaMigration.normalized_versions
 
-          MigrationProxy.new(name, version, file, scope)
-        end
+      file_list = migration_files.map do |file|
+        version, name, scope = parse_migration_filename(file)
+        raise IllegalMigrationNameError.new(file) unless version
+        version = ActiveRecord::SchemaMigration.normalize_migration_number(version)
+        status = db_list.delete(version) ? "up" : "down"
+        [status, version, (name + scope).humanize]
+      end.compact
 
-        migrations.sort_by(&:version)
+      db_list.map! do |version|
+        ["up", version, "********** NO FILE **********"]
       end
 
-      def migrations_status(paths)
-        paths = Array(paths)
-
-        db_list = ActiveRecord::SchemaMigration.normalized_versions
+      (db_list + file_list).sort_by { |_, version, _| version }
+    end
 
-        file_list = migration_files(paths).map do |file|
-          version, name, scope = parse_migration_filename(file)
-          raise IllegalMigrationNameError.new(file) unless version
-          version = ActiveRecord::SchemaMigration.normalize_migration_number(version)
-          status = db_list.delete(version) ? "up" : "down"
-          [status, version, (name + scope).humanize]
-        end.compact
+    def migration_files
+      paths = Array(migrations_paths)
+      Dir[*paths.flat_map { |path| "#{path}/**/[0-9]*_*.rb" }]
+    end
 
-        db_list.map! do |version|
-          ["up", version, "********** NO FILE **********"]
-        end
+    def current_environment
+      ActiveRecord::ConnectionHandling::DEFAULT_ENV.call
+    end
 
-        (db_list + file_list).sort_by { |_, version, _| version }
-      end
+    def protected_environment?
+      ActiveRecord::Base.protected_environments.include?(last_stored_environment) if last_stored_environment
+    end
 
-      def migration_files(paths)
-        Dir[*paths.flat_map { |path| "#{path}/**/[0-9]*_*.rb" }]
-      end
+    def last_stored_environment
+      return nil if current_version == 0
+      raise NoEnvironmentInSchemaError unless ActiveRecord::InternalMetadata.table_exists?
 
-      private
+      environment = ActiveRecord::InternalMetadata[:environment]
+      raise NoEnvironmentInSchemaError unless environment
+      environment
+    end
 
-      def move(direction, migrations_paths, steps)
-        migrator = new(direction, migrations(migrations_paths))
+    private
+      def move(direction, steps)
+        migrator = Migrator.new(direction, migrations)
 
         if current_version != 0 && !migrator.current_migration
           raise UnknownMigrationVersionError.new(current_version)
@@ -1137,10 +1153,29 @@ def move(direction, migrations_paths, steps)
 
         finish = migrator.migrations[start_index + steps]
         version = finish ? finish.version : 0
-        send(direction, migrations_paths, version)
+        send(direction, version)
+      end
+  end
+
+  class Migrator # :nodoc:
+    class << self
+      attr_accessor :migrations_paths
+
+      def migrations_path=(path)
+        ActiveSupport::Deprecation.warn \
+          "ActiveRecord::Migrator.migrations_paths= is now deprecated and will be removed in Rails 6.0." \
+          "You can set the `migrations_paths` on the `connection` instead through the `database.yml`."
+        self.migrations_paths = [path]
+      end
+
+      # For cases where a table doesn't exist like loading from schema cache
+      def current_version(connection = nil)
+        MigrationContext.new(migrations_paths).current_version(connection)
       end
     end
 
+    self.migrations_paths = ["db/migrate"]
+
     def initialize(direction, migrations, target_version = nil)
       @direction         = direction
       @target_version    = target_version
@@ -1203,7 +1238,7 @@ def migrated
     end
 
     def load_migrated
-      @migrated_versions = Set.new(self.class.get_all_versions)
+      @migrated_versions = Set.new(Base.connection.migration_context.get_all_versions)
     end
 
     private
@@ -1235,7 +1270,7 @@ def migrate_without_lock
       # Stores the current environment in the database.
       def record_environment
         return if down?
-        ActiveRecord::InternalMetadata[:environment] = ActiveRecord::Migrator.current_environment
+        ActiveRecord::InternalMetadata[:environment] = ActiveRecord::Base.connection.migration_context.current_environment
       end
 
       def ran?(migration)
@@ -1294,23 +1329,6 @@ def record_version_state_after_migrating(version)
         end
       end
 
-      def self.last_stored_environment
-        return nil if current_version == 0
-        raise NoEnvironmentInSchemaError unless ActiveRecord::InternalMetadata.table_exists?
-
-        environment = ActiveRecord::InternalMetadata[:environment]
-        raise NoEnvironmentInSchemaError unless environment
-        environment
-      end
-
-      def self.current_environment
-        ActiveRecord::ConnectionHandling::DEFAULT_ENV.call
-      end
-
-      def self.protected_environment?
-        ActiveRecord::Base.protected_environments.include?(last_stored_environment) if last_stored_environment
-      end
-
       def up?
         @direction == :up
       end

activerecord/lib/active_record/railtie.rb

@@ -91,6 +91,7 @@ class Railtie < Rails::Railtie # :nodoc:
 
             if File.file?(filename)
               current_version = ActiveRecord::Migrator.current_version
+
               next if current_version.nil?
 
               cache = YAML.load(File.read(filename))

activerecord/lib/active_record/railties/databases.rake

@@ -6,7 +6,7 @@ db_namespace = namespace :db do
   desc "Set the environment value for the database"
   task "environment:set" => :load_config do
     ActiveRecord::InternalMetadata.create_table
-    ActiveRecord::InternalMetadata[:environment] = ActiveRecord::Migrator.current_environment
+    ActiveRecord::InternalMetadata[:environment] = ActiveRecord::Base.connection.migration_context.current_environment
   end
 
   task check_protected_environments: :load_config do
@@ -99,9 +99,8 @@ db_namespace = namespace :db do
 
       ActiveRecord::Tasks::DatabaseTasks.check_target_version
 
-      ActiveRecord::Migrator.run(
+      ActiveRecord::Base.connection.migration_context.run(
         :up,
-        ActiveRecord::Tasks::DatabaseTasks.migrations_paths,
         ActiveRecord::Tasks::DatabaseTasks.target_version
       )
       db_namespace["_dump"].invoke
@@ -113,9 +112,8 @@ db_namespace = namespace :db do
 
       ActiveRecord::Tasks::DatabaseTasks.check_target_version
 
-      ActiveRecord::Migrator.run(
+      ActiveRecord::Base.connection.migration_context.run(
         :down,
-        ActiveRecord::Tasks::DatabaseTasks.migrations_paths,
         ActiveRecord::Tasks::DatabaseTasks.target_version
       )
       db_namespace["_dump"].invoke
@@ -131,8 +129,7 @@ db_namespace = namespace :db do
       puts "\ndatabase: #{ActiveRecord::Base.connection_config[:database]}\n\n"
       puts "#{'Status'.center(8)}  #{'Migration ID'.ljust(14)}  Migration Name"
       puts "-" * 50
-      paths = ActiveRecord::Tasks::DatabaseTasks.migrations_paths
-      ActiveRecord::Migrator.migrations_status(paths).each do |status, version, name|
+      ActiveRecord::Base.connection.migration_context.migrations_status.each do |status, version, name|
         puts "#{status.center(8)}  #{version.ljust(14)}  #{name}"
       end
       puts
@@ -142,14 +139,14 @@ db_namespace = namespace :db do
   desc "Rolls the schema back to the previous version (specify steps w/ STEP=n)."
   task rollback: :load_config do
     step = ENV["STEP"] ? ENV["STEP"].to_i : 1
-    ActiveRecord::Migrator.rollback(ActiveRecord::Tasks::DatabaseTasks.migrations_paths, step)
+    ActiveRecord::Base.connection.migration_context.rollback(step)
     db_namespace["_dump"].invoke
   end
 
   # desc 'Pushes the schema to the next version (specify steps w/ STEP=n).'
   task forward: :load_config do
     step = ENV["STEP"] ? ENV["STEP"].to_i : 1
-    ActiveRecord::Migrator.forward(ActiveRecord::Tasks::DatabaseTasks.migrations_paths, step)
+    ActiveRecord::Base.connection.migration_context.forward(step)
     db_namespace["_dump"].invoke
   end
 
@@ -172,12 +169,12 @@ db_namespace = namespace :db do
 
   desc "Retrieves the current schema version number"
   task version: :load_config do
-    puts "Current version: #{ActiveRecord::Migrator.current_version}"
+    puts "Current version: #{ActiveRecord::Base.connection.migration_context.current_version}"
   end
 
   # desc "Raises an error if there are pending migrations"
   task abort_if_pending_migrations: :load_config do
-    pending_migrations = ActiveRecord::Migrator.open(ActiveRecord::Tasks::DatabaseTasks.migrations_paths).pending_migrations
+    pending_migrations = ActiveRecord::Base.connection.migration_context.open.pending_migrations
 
     if pending_migrations.any?
       puts "You have #{pending_migrations.size} pending #{pending_migrations.size > 1 ? 'migrations:' : 'migration:'}"

activerecord/lib/active_record/schema.rb

@@ -55,7 +55,7 @@ def define(info, &block) # :nodoc:
       end
 
       ActiveRecord::InternalMetadata.create_table
-      ActiveRecord::InternalMetadata[:environment] = ActiveRecord::Migrator.current_environment
+      ActiveRecord::InternalMetadata[:environment] = connection.migration_context.current_environment
     end
 
     private

activerecord/lib/active_record/schema_dumper.rb

@@ -44,7 +44,7 @@ def dump(stream)
 
       def initialize(connection, options = {})
         @connection = connection
-        @version = Migrator::current_version rescue nil
+        @version = connection.migration_context.current_version rescue nil
         @options = options
       end
 

activerecord/lib/active_record/tasks/database_tasks.rb

@@ -54,10 +54,10 @@ module DatabaseTasks
 
       def check_protected_environments!
         unless ENV["DISABLE_DATABASE_ENVIRONMENT_CHECK"]
-          current = ActiveRecord::Migrator.current_environment
-          stored  = ActiveRecord::Migrator.last_stored_environment
+          current = ActiveRecord::Base.connection.migration_context.current_environment
+          stored  = ActiveRecord::Base.connection.migration_context.last_stored_environment
 
-          if ActiveRecord::Migrator.protected_environment?
+          if ActiveRecord::Base.connection.migration_context.protected_environment?
             raise ActiveRecord::ProtectedEnvironmentError.new(stored)
           end
 
@@ -85,6 +85,10 @@ def migrations_paths
         @migrations_paths ||= Rails.application.paths["db/migrate"].to_a
       end
 
+      def migration_context
+        MigrationContext.new(migrations_paths)
+      end
+
       def fixtures_path
         @fixtures_path ||= if ENV["FIXTURES_PATH"]
           File.join(root, ENV["FIXTURES_PATH"])
@@ -169,7 +173,7 @@ def migrate
         verbose = ENV["VERBOSE"] ? ENV["VERBOSE"] != "false" : true
         scope = ENV["SCOPE"]
         verbose_was, Migration.verbose = Migration.verbose, verbose
-        Migrator.migrate(migrations_paths, target_version) do |migration|
+        Base.connection.migration_context.migrate(target_version) do |migration|
           scope.blank? || scope == migration.scope
         end
         ActiveRecord::Base.clear_cache!

activerecord/test/cases/adapters/mysql2/schema_migrations_test.rb

@@ -36,7 +36,7 @@ def test_initializes_internal_metadata_for_encoding_utf8mb4
       assert connection.column_exists?(table_name, :key, :string)
     end
   ensure
-    ActiveRecord::InternalMetadata[:environment] = ActiveRecord::Migrator.current_environment
+    ActiveRecord::InternalMetadata[:environment] = connection.migration_context.current_environment
   end
 
   private

activerecord/test/cases/ar_schema_test.rb

@@ -48,7 +48,7 @@ def test_schema_define
 
     assert_nothing_raised { @connection.select_all "SELECT * FROM fruits" }
     assert_nothing_raised { @connection.select_all "SELECT * FROM schema_migrations" }
-    assert_equal 7, ActiveRecord::Migrator::current_version
+    assert_equal 7, @connection.migration_context.current_version
   end
 
   def test_schema_define_w_table_name_prefix
@@ -64,7 +64,7 @@ def test_schema_define_w_table_name_prefix
         t.column :flavor, :string
       end
     end
-    assert_equal 7, ActiveRecord::Migrator::current_version
+    assert_equal 7, @connection.migration_context.current_version
   ensure
     ActiveRecord::Base.table_name_prefix = old_table_name_prefix
     ActiveRecord::SchemaMigration.table_name = table_name

activerecord/test/cases/migration/pending_migrations_test.rb

@@ -4,37 +4,37 @@
 
 module ActiveRecord
   class Migration
-    class PendingMigrationsTest < ActiveRecord::TestCase
-      def setup
-        super
-        @connection = Minitest::Mock.new
-        @app = Minitest::Mock.new
-        conn = @connection
-        @pending = Class.new(CheckPending) {
-          define_method(:connection) { conn }
-        }.new(@app)
-        @pending.instance_variable_set :@last_check, -1 # Force checking
-      end
+    if current_adapter?(:SQLite3Adapter) && !in_memory_db?
+      class PendingMigrationsTest < ActiveRecord::TestCase
+        setup do
+          file = ActiveRecord::Base.connection.raw_connection.filename
+          @conn = ActiveRecord::Base.establish_connection adapter: "sqlite3", database: ":memory:", migrations_paths: MIGRATIONS_ROOT + "/valid"
+          source_db = SQLite3::Database.new file
+          dest_db = ActiveRecord::Base.connection.raw_connection
+          backup = SQLite3::Backup.new(dest_db, "main", source_db, "main")
+          backup.step(-1)
+          backup.finish
+        end
 
-      def teardown
-        assert @connection.verify
-        assert @app.verify
-        super
-      end
+        teardown do
+          @conn.release_connection if @conn
+          ActiveRecord::Base.establish_connection :arunit
+        end
+
+        def test_errors_if_pending
+          ActiveRecord::Base.connection.drop_table "schema_migrations", if_exists: true
 
-      def test_errors_if_pending
-        ActiveRecord::Migrator.stub :needs_migration?, true do
-          assert_raise ActiveRecord::PendingMigrationError do
-            @pending.call(nil)
+          assert_raises ActiveRecord::PendingMigrationError do
+            CheckPending.new(Proc.new {}).call({})
           end
         end
-      end
 
-      def test_checks_if_supported
-        @app.expect :call, nil, [:foo]
+        def test_checks_if_supported
+          ActiveRecord::SchemaMigration.create_table
+          migrator = Base.connection.migration_context
+          capture(:stdout) { migrator.migrate }
 
-        ActiveRecord::Migrator.stub :needs_migration?, false do
-          @pending.call(:foo)
+          assert_nil CheckPending.new(Proc.new {}).call({})
         end
       end
     end

activerecord/test/cases/migration_test.rb

@@ -71,6 +71,16 @@ def setup
     ActiveRecord::Migration.verbose = @verbose_was
   end
 
+  def test_migrator_migrations_path_is_deprecated
+    assert_deprecated do
+      ActiveRecord::Migrator.migrations_path = "/whatever"
+    end
+  ensure
+    assert_deprecated do
+      ActiveRecord::Migrator.migrations_path = "db/migrate"
+    end
+  end
+
   def test_migration_version_matches_component_version
     assert_equal ActiveRecord::VERSION::STRING.to_f, ActiveRecord::Migration.current_version
   end
@@ -78,20 +88,20 @@ def test_migration_version_matches_component_version
   def test_migrator_versions
     migrations_path = MIGRATIONS_ROOT + "/valid"
     old_path = ActiveRecord::Migrator.migrations_paths
-    ActiveRecord::Migrator.migrations_paths = migrations_path
+    migrator = ActiveRecord::MigrationContext.new(migrations_path)
 
-    ActiveRecord::Migrator.up(migrations_path)
-    assert_equal 3, ActiveRecord::Migrator.current_version
-    assert_equal false, ActiveRecord::Migrator.needs_migration?
+    migrator.up
+    assert_equal 3, migrator.current_version
+    assert_equal false, migrator.needs_migration?
 
-    ActiveRecord::Migrator.down(MIGRATIONS_ROOT + "/valid")
-    assert_equal 0, ActiveRecord::Migrator.current_version
-    assert_equal true, ActiveRecord::Migrator.needs_migration?
+    migrator.down
+    assert_equal 0, migrator.current_version
+    assert_equal true, migrator.needs_migration?
 
     ActiveRecord::SchemaMigration.create!(version: 3)
-    assert_equal true, ActiveRecord::Migrator.needs_migration?
+    assert_equal true, migrator.needs_migration?
   ensure
-    ActiveRecord::Migrator.migrations_paths = old_path
+    ActiveRecord::MigrationContext.new(old_path)
   end
 
   def test_migration_detection_without_schema_migration_table
@@ -99,28 +109,31 @@ def test_migration_detection_without_schema_migration_table
 
     migrations_path = MIGRATIONS_ROOT + "/valid"
     old_path = ActiveRecord::Migrator.migrations_paths
-    ActiveRecord::Migrator.migrations_paths = migrations_path
+    migrator = ActiveRecord::MigrationContext.new(migrations_path)
 
-    assert_equal true, ActiveRecord::Migrator.needs_migration?
+    assert_equal true, migrator.needs_migration?
   ensure
-    ActiveRecord::Migrator.migrations_paths = old_path
+    ActiveRecord::MigrationContext.new(old_path)
   end
 
   def test_any_migrations
     old_path = ActiveRecord::Migrator.migrations_paths
-    ActiveRecord::Migrator.migrations_paths = MIGRATIONS_ROOT + "/valid"
+    migrator = ActiveRecord::MigrationContext.new(MIGRATIONS_ROOT + "/valid")
 
-    assert ActiveRecord::Migrator.any_migrations?
+    assert migrator.any_migrations?
 
-    ActiveRecord::Migrator.migrations_paths = MIGRATIONS_ROOT + "/empty"
+    migrator_empty = ActiveRecord::MigrationContext.new(MIGRATIONS_ROOT + "/empty")
 
-    assert_not ActiveRecord::Migrator.any_migrations?
+    assert_not migrator_empty.any_migrations?
   ensure
-    ActiveRecord::Migrator.migrations_paths = old_path
+    ActiveRecord::MigrationContext.new(old_path)
   end
 
   def test_migration_version
-    assert_nothing_raised { ActiveRecord::Migrator.run(:up, MIGRATIONS_ROOT + "/version_check", 20131219224947) }
+    migrator = ActiveRecord::MigrationContext.new(MIGRATIONS_ROOT + "/version_check")
+    assert_equal 0, migrator.current_version
+    migrator.up(20131219224947)
+    assert_equal 20131219224947, migrator.current_version
   end
 
   def test_create_table_with_force_true_does_not_drop_nonexisting_table
@@ -219,12 +232,13 @@ def test_filtering_migrations
     assert !Reminder.table_exists?
 
     name_filter = lambda { |migration| migration.name == "ValidPeopleHaveLastNames" }
-    ActiveRecord::Migrator.up(MIGRATIONS_ROOT + "/valid", &name_filter)
+    migrator = ActiveRecord::MigrationContext.new(MIGRATIONS_ROOT + "/valid")
+    migrator.up(&name_filter)
 
     assert_column Person, :last_name
     assert_raise(ActiveRecord::StatementInvalid) { Reminder.first }
 
-    ActiveRecord::Migrator.down(MIGRATIONS_ROOT + "/valid", &name_filter)
+    migrator.down(&name_filter)
 
     assert_no_column Person, :last_name
     assert_raise(ActiveRecord::StatementInvalid) { Reminder.first }
@@ -382,9 +396,9 @@ def test_internal_metadata_stores_environment
     current_env     = ActiveRecord::ConnectionHandling::DEFAULT_ENV.call
     migrations_path = MIGRATIONS_ROOT + "/valid"
     old_path        = ActiveRecord::Migrator.migrations_paths
-    ActiveRecord::Migrator.migrations_paths = migrations_path
+    migrator = ActiveRecord::MigrationContext.new(migrations_path)
 
-    ActiveRecord::Migrator.up(migrations_path)
+    migrator.up
     assert_equal current_env, ActiveRecord::InternalMetadata[:environment]
 
     original_rails_env  = ENV["RAILS_ENV"]
@@ -395,13 +409,13 @@ def test_internal_metadata_stores_environment
     refute_equal current_env, new_env
 
     sleep 1 # mysql by default does not store fractional seconds in the database
-    ActiveRecord::Migrator.up(migrations_path)
+    migrator.up
     assert_equal new_env, ActiveRecord::InternalMetadata[:environment]
   ensure
-    ActiveRecord::Migrator.migrations_paths = old_path
+    migrator = ActiveRecord::MigrationContext.new(old_path)
     ENV["RAILS_ENV"] = original_rails_env
     ENV["RACK_ENV"]  = original_rack_env
-    ActiveRecord::Migrator.up(migrations_path)
+    migrator.up
   end
 
   def test_internal_metadata_stores_environment_when_other_data_exists
@@ -411,14 +425,15 @@ def test_internal_metadata_stores_environment_when_other_data_exists
     current_env     = ActiveRecord::ConnectionHandling::DEFAULT_ENV.call
     migrations_path = MIGRATIONS_ROOT + "/valid"
     old_path        = ActiveRecord::Migrator.migrations_paths
-    ActiveRecord::Migrator.migrations_paths = migrations_path
 
     current_env = ActiveRecord::ConnectionHandling::DEFAULT_ENV.call
-    ActiveRecord::Migrator.up(migrations_path)
+    migrator = ActiveRecord::MigrationContext.new(migrations_path)
+    migrator.up
     assert_equal current_env, ActiveRecord::InternalMetadata[:environment]
     assert_equal "bar", ActiveRecord::InternalMetadata[:foo]
   ensure
-    ActiveRecord::Migrator.migrations_paths = old_path
+    migrator = ActiveRecord::MigrationContext.new(old_path)
+    migrator.up
   end
 
   def test_proper_table_name_on_migration

activerecord/test/cases/migrator_test.rb

@@ -89,7 +89,7 @@ def test_migrator_with_missing_version_numbers
   end
 
   def test_finds_migrations
-    migrations = ActiveRecord::Migrator.migrations(MIGRATIONS_ROOT + "/valid")
+    migrations = ActiveRecord::MigrationContext.new(MIGRATIONS_ROOT + "/valid").migrations
 
     [[1, "ValidPeopleHaveLastNames"], [2, "WeNeedReminders"], [3, "InnocentJointable"]].each_with_index do |pair, i|
       assert_equal migrations[i].version, pair.first
@@ -98,7 +98,8 @@ def test_finds_migrations
   end
 
   def test_finds_migrations_in_subdirectories
-    migrations = ActiveRecord::Migrator.migrations(MIGRATIONS_ROOT + "/valid_with_subdirectories")
+    migrations = ActiveRecord::MigrationContext.new(MIGRATIONS_ROOT + "/valid_with_subdirectories").migrations
+
 
     [[1, "ValidPeopleHaveLastNames"], [2, "WeNeedReminders"], [3, "InnocentJointable"]].each_with_index do |pair, i|
       assert_equal migrations[i].version, pair.first
@@ -108,7 +109,7 @@ def test_finds_migrations_in_subdirectories
 
   def test_finds_migrations_from_two_directories
     directories = [MIGRATIONS_ROOT + "/valid_with_timestamps", MIGRATIONS_ROOT + "/to_copy_with_timestamps"]
-    migrations = ActiveRecord::Migrator.migrations directories
+    migrations = ActiveRecord::MigrationContext.new(directories).migrations
 
     [[20090101010101, "PeopleHaveHobbies"],
      [20090101010202, "PeopleHaveDescriptions"],
@@ -121,14 +122,14 @@ def test_finds_migrations_from_two_directories
   end
 
   def test_finds_migrations_in_numbered_directory
-    migrations = ActiveRecord::Migrator.migrations [MIGRATIONS_ROOT + "/10_urban"]
+    migrations = ActiveRecord::MigrationContext.new(MIGRATIONS_ROOT + "/10_urban").migrations
     assert_equal 9, migrations[0].version
     assert_equal "AddExpressions", migrations[0].name
   end
 
   def test_relative_migrations
     list = Dir.chdir(MIGRATIONS_ROOT) do
-      ActiveRecord::Migrator.migrations("valid")
+      ActiveRecord::MigrationContext.new("valid").migrations
     end
 
     migration_proxy = list.find { |item|
@@ -157,7 +158,7 @@ def test_migrations_status
       ["up",   "002", "We need reminders"],
       ["down", "003", "Innocent jointable"],
       ["up",   "010", "********** NO FILE **********"],
-    ], ActiveRecord::Migrator.migrations_status(path)
+    ], ActiveRecord::MigrationContext.new(path).migrations_status
   end
 
   def test_migrations_status_in_subdirectories
@@ -171,24 +172,20 @@ def test_migrations_status_in_subdirectories
       ["up",   "002", "We need reminders"],
       ["down", "003", "Innocent jointable"],
       ["up",   "010", "********** NO FILE **********"],
-    ], ActiveRecord::Migrator.migrations_status(path)
+    ], ActiveRecord::MigrationContext.new(path).migrations_status
   end
 
   def test_migrations_status_with_schema_define_in_subdirectories
-    path = MIGRATIONS_ROOT + "/valid_with_subdirectories"
-    prev_paths = ActiveRecord::Migrator.migrations_paths
-    ActiveRecord::Migrator.migrations_paths = path
+    _, migrator = migrator_class(3)
+    migrator = migrator.new("valid_with_subdirectories")
 
-    ActiveRecord::Schema.define(version: 3) do
-    end
+    migrator.migrate
 
     assert_equal [
-      ["up", "001", "Valid people have last names"],
-      ["up", "002", "We need reminders"],
-      ["up", "003", "Innocent jointable"],
-    ], ActiveRecord::Migrator.migrations_status(path)
-  ensure
-    ActiveRecord::Migrator.migrations_paths = prev_paths
+      ["up", "001", "********** NO FILE **********"],
+      ["up", "002", "********** NO FILE **********"],
+      ["up", "003", "********** NO FILE **********"],
+    ], migrator.migrations_status
   end
 
   def test_migrations_status_from_two_directories
@@ -204,7 +201,7 @@ def test_migrations_status_from_two_directories
       ["down", "20100201010101", "Valid with timestamps we need reminders"],
       ["down", "20100301010101", "Valid with timestamps innocent jointable"],
       ["up",   "20160528010101", "********** NO FILE **********"],
-    ], ActiveRecord::Migrator.migrations_status(paths)
+    ], ActiveRecord::MigrationContext.new(paths).migrations_status
   end
 
   def test_migrator_interleaved_migrations
@@ -232,25 +229,28 @@ def test_migrator_interleaved_migrations
 
   def test_up_calls_up
     migrations = [Sensor.new(nil, 0), Sensor.new(nil, 1), Sensor.new(nil, 2)]
-    ActiveRecord::Migrator.new(:up, migrations).migrate
+    migrator = ActiveRecord::Migrator.new(:up, migrations)
+    migrator.migrate
     assert migrations.all?(&:went_up)
     assert migrations.all? { |m| !m.went_down }
-    assert_equal 2, ActiveRecord::Migrator.current_version
+    assert_equal 2, migrator.current_version
   end
 
   def test_down_calls_down
     test_up_calls_up
 
     migrations = [Sensor.new(nil, 0), Sensor.new(nil, 1), Sensor.new(nil, 2)]
-    ActiveRecord::Migrator.new(:down, migrations).migrate
+    migrator = ActiveRecord::Migrator.new(:down, migrations)
+    migrator.migrate
     assert migrations.all? { |m| !m.went_up }
     assert migrations.all?(&:went_down)
-    assert_equal 0, ActiveRecord::Migrator.current_version
+    assert_equal 0, migrator.current_version
   end
 
   def test_current_version
     ActiveRecord::SchemaMigration.create!(version: "1000")
-    assert_equal 1000, ActiveRecord::Migrator.current_version
+    migrator = ActiveRecord::MigrationContext.new("db/migrate")
+    assert_equal 1000, migrator.current_version
   end
 
   def test_migrator_one_up
@@ -289,33 +289,36 @@ def test_migrator_one_up_one_down
 
   def test_migrator_double_up
     calls, migrations = sensors(3)
-    assert_equal(0, ActiveRecord::Migrator.current_version)
+    migrator = ActiveRecord::Migrator.new(:up, migrations, 1)
+    assert_equal(0, migrator.current_version)
 
-    ActiveRecord::Migrator.new(:up, migrations, 1).migrate
+    migrator.migrate
     assert_equal [[:up, 1]], calls
     calls.clear
 
-    ActiveRecord::Migrator.new(:up, migrations, 1).migrate
+    migrator.migrate
     assert_equal [], calls
   end
 
   def test_migrator_double_down
     calls, migrations = sensors(3)
+    migrator = ActiveRecord::Migrator.new(:up, migrations, 1)
 
-    assert_equal(0, ActiveRecord::Migrator.current_version)
+    assert_equal 0, migrator.current_version
 
-    ActiveRecord::Migrator.new(:up, migrations, 1).run
+    migrator.run
     assert_equal [[:up, 1]], calls
     calls.clear
 
-    ActiveRecord::Migrator.new(:down, migrations, 1).run
+    migrator = ActiveRecord::Migrator.new(:down, migrations, 1)
+    migrator.run
     assert_equal [[:down, 1]], calls
     calls.clear
 
-    ActiveRecord::Migrator.new(:down, migrations, 1).run
+    migrator.run
     assert_equal [], calls
 
-    assert_equal(0, ActiveRecord::Migrator.current_version)
+    assert_equal 0, migrator.current_version
   end
 
   def test_migrator_verbosity
@@ -361,78 +364,85 @@ def test_target_version_zero_should_run_only_once
 
   def test_migrator_going_down_due_to_version_target
     calls, migrator = migrator_class(3)
+    migrator = migrator.new("valid")
 
-    migrator.up("valid", 1)
+    migrator.up(1)
     assert_equal [[:up, 1]], calls
     calls.clear
 
-    migrator.migrate("valid", 0)
+    migrator.migrate(0)
     assert_equal [[:down, 1]], calls
     calls.clear
 
-    migrator.migrate("valid")
+    migrator.migrate
     assert_equal [[:up, 1], [:up, 2], [:up, 3]], calls
   end
 
   def test_migrator_output_when_running_multiple_migrations
     _, migrator = migrator_class(3)
+    migrator = migrator.new("valid")
 
-    result = migrator.migrate("valid")
+    result = migrator.migrate
     assert_equal(3, result.count)
 
     # Nothing migrated from duplicate run
-    result = migrator.migrate("valid")
+    result = migrator.migrate
     assert_equal(0, result.count)
 
-    result = migrator.rollback("valid")
+    result = migrator.rollback
     assert_equal(1, result.count)
   end
 
   def test_migrator_output_when_running_single_migration
     _, migrator = migrator_class(1)
-    result = migrator.run(:up, "valid", 1)
+    migrator = migrator.new("valid")
+
+    result = migrator.run(:up, 1)
 
     assert_equal(1, result.version)
   end
 
   def test_migrator_rollback
     _, migrator = migrator_class(3)
+    migrator = migrator.new("valid")
 
-    migrator.migrate("valid")
-    assert_equal(3, ActiveRecord::Migrator.current_version)
+    migrator.migrate
+    assert_equal(3, migrator.current_version)
 
-    migrator.rollback("valid")
-    assert_equal(2, ActiveRecord::Migrator.current_version)
+    migrator.rollback
+    assert_equal(2, migrator.current_version)
 
-    migrator.rollback("valid")
-    assert_equal(1, ActiveRecord::Migrator.current_version)
+    migrator.rollback
+    assert_equal(1, migrator.current_version)
 
-    migrator.rollback("valid")
-    assert_equal(0, ActiveRecord::Migrator.current_version)
+    migrator.rollback
+    assert_equal(0, migrator.current_version)
 
-    migrator.rollback("valid")
-    assert_equal(0, ActiveRecord::Migrator.current_version)
+    migrator.rollback
+    assert_equal(0, migrator.current_version)
   end
 
   def test_migrator_db_has_no_schema_migrations_table
     _, migrator = migrator_class(3)
+    migrator = migrator.new("valid")
 
     ActiveRecord::Base.connection.drop_table "schema_migrations", if_exists: true
     assert_not ActiveRecord::Base.connection.table_exists?("schema_migrations")
-    migrator.migrate("valid", 1)
+    migrator.migrate(1)
     assert ActiveRecord::Base.connection.table_exists?("schema_migrations")
   end
 
   def test_migrator_forward
     _, migrator = migrator_class(3)
-    migrator.migrate("/valid", 1)
-    assert_equal(1, ActiveRecord::Migrator.current_version)
+    migrator = migrator.new("/valid")
+    migrator.migrate(1)
+    assert_equal(1, migrator.current_version)
 
-    migrator.forward("/valid", 2)
-    assert_equal(3, ActiveRecord::Migrator.current_version)
+    migrator.forward(2)
+    assert_equal(3, migrator.current_version)
 
-    migrator.forward("/valid")
-    assert_equal(3, ActiveRecord::Migrator.current_version)
+    migrator.forward
+    assert_equal(3, migrator.current_version)
   end
 
   def test_only_loads_pending_migrations
@@ -440,25 +450,27 @@ def test_only_loads_pending_migrations
     ActiveRecord::SchemaMigration.create!(version: "1")
 
     calls, migrator = migrator_class(3)
-    migrator.migrate("valid", nil)
+    migrator = migrator.new("valid")
+    migrator.migrate
 
     assert_equal [[:up, 2], [:up, 3]], calls
   end
 
   def test_get_all_versions
     _, migrator = migrator_class(3)
+    migrator = migrator.new("valid")
 
-    migrator.migrate("valid")
-    assert_equal([1, 2, 3], ActiveRecord::Migrator.get_all_versions)
+    migrator.migrate
+    assert_equal([1, 2, 3], migrator.get_all_versions)
 
-    migrator.rollback("valid")
-    assert_equal([1, 2], ActiveRecord::Migrator.get_all_versions)
+    migrator.rollback
+    assert_equal([1, 2], migrator.get_all_versions)
 
-    migrator.rollback("valid")
-    assert_equal([1], ActiveRecord::Migrator.get_all_versions)
+    migrator.rollback
+    assert_equal([1], migrator.get_all_versions)
 
-    migrator.rollback("valid")
-    assert_equal([], ActiveRecord::Migrator.get_all_versions)
+    migrator.rollback
+    assert_equal([], migrator.get_all_versions)
   end
 
   private
@@ -483,11 +495,11 @@ def sensors(count)
     def migrator_class(count)
       calls, migrations = sensors(count)
 
-      migrator = Class.new(ActiveRecord::Migrator).extend(Module.new {
-        define_method(:migrations) { |paths|
+      migrator = Class.new(ActiveRecord::MigrationContext) {
+        define_method(:migrations) { |*|
           migrations
         }
-      })
+      }
       [calls, migrator]
     end
 end

activerecord/test/cases/tasks/database_tasks_test.rb

@@ -28,10 +28,10 @@ def teardown
 
   class DatabaseTasksUtilsTask < ActiveRecord::TestCase
     def test_raises_an_error_when_called_with_protected_environment
-      ActiveRecord::Migrator.stubs(:current_version).returns(1)
+      ActiveRecord::MigrationContext.any_instance.stubs(:current_version).returns(1)
 
       protected_environments = ActiveRecord::Base.protected_environments
-      current_env            = ActiveRecord::Migrator.current_environment
+      current_env            = ActiveRecord::Base.connection.migration_context.current_environment
       assert_not_includes protected_environments, current_env
       # Assert no error
       ActiveRecord::Tasks::DatabaseTasks.check_protected_environments!
@@ -45,10 +45,10 @@ def test_raises_an_error_when_called_with_protected_environment
     end
 
     def test_raises_an_error_when_called_with_protected_environment_which_name_is_a_symbol
-      ActiveRecord::Migrator.stubs(:current_version).returns(1)
+      ActiveRecord::MigrationContext.any_instance.stubs(:current_version).returns(1)
 
       protected_environments = ActiveRecord::Base.protected_environments
-      current_env            = ActiveRecord::Migrator.current_environment
+      current_env            = ActiveRecord::Base.connection.migration_context.current_environment
       assert_not_includes protected_environments, current_env
       # Assert no error
       ActiveRecord::Tasks::DatabaseTasks.check_protected_environments!
@@ -63,7 +63,7 @@ def test_raises_an_error_when_called_with_protected_environment_which_name_is_a_
 
     def test_raises_an_error_if_no_migrations_have_been_made
       ActiveRecord::InternalMetadata.stubs(:table_exists?).returns(false)
-      ActiveRecord::Migrator.stubs(:current_version).returns(1)
+      ActiveRecord::MigrationContext.any_instance.stubs(:current_version).returns(1)
 
       assert_raise(ActiveRecord::NoEnvironmentInSchemaError) do
         ActiveRecord::Tasks::DatabaseTasks.check_protected_environments!
@@ -347,50 +347,92 @@ def test_drops_testand_development_databases_when_rails_env_is_development
     end
   end
 
-  class DatabaseTasksMigrateTest < ActiveRecord::TestCase
-    self.use_transactional_tests = false
+  if current_adapter?(:SQLite3Adapter) && !in_memory_db?
+    class DatabaseTasksMigrateTest < ActiveRecord::TestCase
+      self.use_transactional_tests = false
+
+      # Use a memory db here to avoid having to rollback at the end
+      setup do
+        migrations_path = MIGRATIONS_ROOT + "/valid"
+        file = ActiveRecord::Base.connection.raw_connection.filename
+        @conn = ActiveRecord::Base.establish_connection adapter: "sqlite3",
+          database: ":memory:", migrations_paths: migrations_path
+        source_db = SQLite3::Database.new file
+        dest_db = ActiveRecord::Base.connection.raw_connection
+        backup = SQLite3::Backup.new(dest_db, "main", source_db, "main")
+        backup.step(-1)
+        backup.finish
+      end
 
-    def setup
-      ActiveRecord::Tasks::DatabaseTasks.migrations_paths = "custom/path"
-    end
+      teardown do
+        @conn.release_connection if @conn
+        ActiveRecord::Base.establish_connection :arunit
+      end
 
-    def teardown
-      ActiveRecord::Tasks::DatabaseTasks.migrations_paths = nil
-    end
+      def test_migrate_set_and_unset_verbose_and_version_env_vars
+        verbose, version = ENV["VERBOSE"], ENV["VERSION"]
+        ENV["VERSION"] = "2"
+        ENV["VERBOSE"] = "false"
 
-    def test_migrate_receives_correct_env_vars
-      verbose, version = ENV["VERBOSE"], ENV["VERSION"]
+        # run down migration because it was already run on copied db
+        assert_empty capture_migration_output
 
-      ENV["VERBOSE"] = "false"
-      ENV["VERSION"] = "4"
-      ActiveRecord::Migrator.expects(:migrate).with("custom/path", 4)
-      ActiveRecord::Migration.expects(:verbose=).with(false)
-      ActiveRecord::Migration.expects(:verbose=).with(ActiveRecord::Migration.verbose)
-      ActiveRecord::Tasks::DatabaseTasks.migrate
+        ENV.delete("VERSION")
+        ENV.delete("VERBOSE")
 
-      ENV.delete("VERBOSE")
-      ENV.delete("VERSION")
-      ActiveRecord::Migrator.expects(:migrate).with("custom/path", nil)
-      ActiveRecord::Migration.expects(:verbose=).with(true)
-      ActiveRecord::Migration.expects(:verbose=).with(ActiveRecord::Migration.verbose)
-      ActiveRecord::Tasks::DatabaseTasks.migrate
+        # re-run up migration
+        assert_includes capture_migration_output, "migrating"
+      ensure
+        ENV["VERBOSE"], ENV["VERSION"] = verbose, version
+      end
 
-      ENV["VERBOSE"] = ""
-      ENV["VERSION"] = ""
-      ActiveRecord::Migrator.expects(:migrate).with("custom/path", nil)
-      ActiveRecord::Migration.expects(:verbose=).with(true)
-      ActiveRecord::Migration.expects(:verbose=).with(ActiveRecord::Migration.verbose)
-      ActiveRecord::Tasks::DatabaseTasks.migrate
+      def test_migrate_set_and_unset_empty_values_for_verbose_and_version_env_vars
+        verbose, version = ENV["VERBOSE"], ENV["VERSION"]
 
-      ENV["VERBOSE"] = "yes"
-      ENV["VERSION"] = "0"
-      ActiveRecord::Migrator.expects(:migrate).with("custom/path", 0)
-      ActiveRecord::Migration.expects(:verbose=).with(true)
-      ActiveRecord::Migration.expects(:verbose=).with(ActiveRecord::Migration.verbose)
-      ActiveRecord::Tasks::DatabaseTasks.migrate
-    ensure
-      ENV["VERBOSE"], ENV["VERSION"] = verbose, version
+        ENV["VERSION"] = "2"
+        ENV["VERBOSE"] = "false"
+
+        # run down migration because it was already run on copied db
+        assert_empty capture_migration_output
+
+        ENV["VERBOSE"] = ""
+        ENV["VERSION"] = ""
+
+        # re-run up migration
+        assert_includes capture_migration_output, "migrating"
+      ensure
+        ENV["VERBOSE"], ENV["VERSION"] = verbose, version
+      end
+
+      def test_migrate_set_and_unset_nonsense_values_for_verbose_and_version_env_vars
+        verbose, version = ENV["VERBOSE"], ENV["VERSION"]
+
+        # run down migration because it was already run on copied db
+        ENV["VERSION"] = "2"
+        ENV["VERBOSE"] = "false"
+
+        assert_empty capture_migration_output
+
+        ENV["VERBOSE"] = "yes"
+        ENV["VERSION"] = "2"
+
+        # run no migration because 2 was already run
+        assert_empty capture_migration_output
+      ensure
+        ENV["VERBOSE"], ENV["VERSION"] = verbose, version
+      end
+
+      private
+        def capture_migration_output
+          capture(:stdout) do
+            ActiveRecord::Tasks::DatabaseTasks.migrate
+          end
+        end
     end
+  end
+
+  class DatabaseTasksMigrateErrorTest < ActiveRecord::TestCase
+    self.use_transactional_tests = false
 
     def test_migrate_raise_error_on_invalid_version_format
       version = ENV["VERSION"]

activestorage/test/database/setup.rb

@@ -3,5 +3,5 @@
 require_relative "create_users_migration"
 
 ActiveRecord::Base.establish_connection(adapter: "sqlite3", database: ":memory:")
-ActiveRecord::Migrator.migrate File.expand_path("../../db/migrate", __dir__)
+ActiveRecord::Base.connection.migration_context.migrate
 ActiveStorageCreateUsers.migrate(:up)

railties/lib/rails/info.rb

@@ -99,7 +99,7 @@ def to_html
     end
 
     property "Database schema version" do
-      ActiveRecord::Migrator.current_version rescue nil
+      ActiveRecord::Base.connection.migration_context.current_version rescue nil
     end
   end
 end

railties/test/application/rake/migrations_test.rb

@@ -37,6 +37,18 @@ class AMigration < ActiveRecord::Migration::Current
         assert_match(/AMigration: reverted/, output)
       end
 
+      test "version outputs current version" do
+        app_file "db/migrate/01_one_migration.rb", <<-MIGRATION
+          class OneMigration < ActiveRecord::Migration::Current
+          end
+        MIGRATION
+
+        rails "db:migrate"
+
+        output = rails("db:version")
+        assert_match(/Current version: 1/, output)
+      end
+
       test "migrate with specified VERSION in different formats" do
         app_file "db/migrate/01_one_migration.rb", <<-MIGRATION
           class OneMigration < ActiveRecord::Migration::Current

railties/test/railties/engine_test.rb

@@ -34,7 +34,7 @@ def boot_rails
 
     def migrations
       migration_root = File.expand_path(ActiveRecord::Migrator.migrations_paths.first, app_path)
-      ActiveRecord::Migrator.migrations(migration_root)
+      ActiveRecord::MigrationContext.new(migration_root).migrations
     end
 
     test "serving sprocket's assets" do