From 6d81eab13d65b7239444c9d0bfb14518755ddbc9 Mon Sep 17 00:00:00 2001
From: eileencodes <eileencodes@gmail.com>
Date: Tue, 5 Nov 2019 17:05:54 -0500
Subject: [PATCH] Rename the classes

This commit renames `RoleManager` -> `PoolManager` and `Role` ->
`PoolConfig`.

Once we introduced the previous commit, and looking at the existing
code, it's clearer that `Role` and `RoleManager` are not the right names
for these.

Since this PR moves away from swapping the connection handler concepts
around and the role concept will continue existing on the handler level,
we need to rename this.

A `PoolConfig` holds a `connection_specification_name` (we may rename
this down the road), a `db_config`, a `schema_cache`, and a `pool`. It
does feel like `pool` could eventually hold all of these things instead
of having a `PoolConfig` object. This would remove one level of the
object graph and reduce complexity. For now I'm leaving this object to
keep the change churn low and will revisit later.

Co-authored-by: John Crepezzi <seejohnrun@github.com>
---
 .../lib/active_record/connection_adapters.rb  |  4 +-
 .../abstract/connection_pool.rb               | 66 +++++++--------
 .../{role.rb => pool_config.rb}               |  4 +-
 .../connection_adapters/pool_manager.rb       | 27 ++++++
 .../connection_adapters/resolver.rb           | 12 +--
 .../connection_adapters/role_manager.rb       | 27 ------
 .../lib/active_record/test_fixtures.rb        |  8 +-
 .../adapter_leasing_test.rb                   |  4 +-
 ...ection_handlers_multi_pool_config_test.rb} | 17 ++--
 .../test/cases/connection_pool_test.rb        | 24 +++---
 activerecord/test/cases/disconnected_test.rb  |  4 +-
 activerecord/test/cases/fixtures_test.rb      |  6 +-
 .../resolver_test.rb                          | 82 +++++++++----------
 activerecord/test/cases/query_cache_test.rb   |  6 +-
 activerecord/test/cases/reaper_test.rb        | 38 ++++-----
 activerecord/test/cases/unconnected_test.rb   |  2 +-
 16 files changed, 166 insertions(+), 165 deletions(-)
 rename activerecord/lib/active_record/connection_adapters/{role.rb => pool_config.rb} (94%)
 create mode 100644 activerecord/lib/active_record/connection_adapters/pool_manager.rb
 delete mode 100644 activerecord/lib/active_record/connection_adapters/role_manager.rb
 rename activerecord/test/cases/connection_adapters/{connection_handlers_multi_role_test.rb => connection_handlers_multi_pool_config_test.rb} (86%)
 rename activerecord/test/cases/{connection_specification => pool_config}/resolver_test.rb (57%)

diff --git a/activerecord/lib/active_record/connection_adapters.rb b/activerecord/lib/active_record/connection_adapters.rb
index d7626150c9..ed3790d2ec 100644
--- a/activerecord/lib/active_record/connection_adapters.rb
+++ b/activerecord/lib/active_record/connection_adapters.rb
@@ -9,8 +9,8 @@ module ActiveRecord
     end
 
     autoload :Column
-    autoload :Role
-    autoload :RoleManager
+    autoload :PoolConfig
+    autoload :PoolManager
     autoload :Resolver
 
     autoload_at "active_record/connection_adapters/abstract/schema_definitions" do
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
index 3b5c23d2fb..c9fd12cd8b 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
@@ -370,21 +370,21 @@ module ActiveRecord
       include ConnectionAdapters::AbstractPool
 
       attr_accessor :automatic_reconnect, :checkout_timeout
-      attr_reader :db_config, :size, :reaper, :role
+      attr_reader :db_config, :size, :reaper, :pool_config
 
-      delegate :schema_cache, :schema_cache=, to: :role
+      delegate :schema_cache, :schema_cache=, to: :pool_config
 
-      # Creates a new ConnectionPool object. +role+ is a Role
+      # Creates a new ConnectionPool object. +pool_config+ is a PoolConfig
       # object which describes database connection information (e.g. adapter,
       # host name, username, password, etc), as well as the maximum size for
       # this ConnectionPool.
       #
       # The default ConnectionPool maximum size is 5.
-      def initialize(role)
+      def initialize(pool_config)
         super()
 
-        @role = role
-        @db_config = role.db_config
+        @pool_config = pool_config
+        @db_config = pool_config.db_config
 
         @checkout_timeout = db_config.checkout_timeout
         @idle_timeout = db_config.idle_timeout
@@ -1003,8 +1003,8 @@ module ActiveRecord
       private_constant :FINALIZER
 
       def initialize
-        # These caches are keyed by role.connection_specification_name (Role#connection_specification_name).
-        @owner_to_role_manager = Concurrent::Map.new(initial_capacity: 2)
+        # These caches are keyed by pool_config.connection_specification_name (PoolConfig#connection_specification_name).
+        @owner_to_pool_manager = Concurrent::Map.new(initial_capacity: 2)
 
         # Backup finalizer: if the forked child skipped Kernel#fork the early discard has not occurred
         ObjectSpace.define_finalizer self, FINALIZER
@@ -1031,36 +1031,36 @@ module ActiveRecord
       end
 
       def connection_pool_names # :nodoc:
-        owner_to_role_manager.keys
+        owner_to_pool_manager.keys
       end
 
       def connection_pool_list
-        owner_to_role_manager.values.compact.flat_map { |rc| rc.roles.map(&:pool) }
+        owner_to_pool_manager.values.compact.flat_map { |m| m.pool_configs.map(&:pool) }
       end
       alias :connection_pools :connection_pool_list
 
-      def establish_connection(config, role_name = :default)
+      def establish_connection(config, pool_key = :default)
         resolver = Resolver.new(Base.configurations)
-        role = resolver.resolve_role(config)
-        db_config = role.db_config
+        pool_config = resolver.resolve_pool_config(config)
+        db_config = pool_config.db_config
 
-        remove_connection(role.connection_specification_name, role_name)
+        remove_connection(pool_config.connection_specification_name, pool_key)
 
         message_bus = ActiveSupport::Notifications.instrumenter
         payload = {
           connection_id: object_id
         }
-        if role
-          payload[:spec_name] = role.connection_specification_name
+        if pool_config
+          payload[:spec_name] = pool_config.connection_specification_name
           payload[:config] = db_config.configuration_hash
         end
 
-        owner_to_role_manager[role.connection_specification_name] ||= RoleManager.new
-        role_manager = owner_to_role_manager[role.connection_specification_name]
-        role_manager.set_role(role_name, role)
+        owner_to_pool_manager[pool_config.connection_specification_name] ||= PoolManager.new
+        pool_manager = owner_to_pool_manager[pool_config.connection_specification_name]
+        pool_manager.set_pool_config(pool_key, pool_config)
 
         message_bus.instrument("!connection.active_record", payload) do
-          role.pool
+          pool_config.pool
         end
       end
 
@@ -1116,8 +1116,8 @@ module ActiveRecord
 
       # Returns true if a connection that's accessible to this class has
       # already been opened.
-      def connected?(spec_name, role_name = :default)
-        pool = retrieve_connection_pool(spec_name, role_name)
+      def connected?(spec_name, pool_key = :default)
+        pool = retrieve_connection_pool(spec_name, pool_key)
         pool && pool.connected?
       end
 
@@ -1125,27 +1125,27 @@ module ActiveRecord
       # connection and the defined connection (if they exist). The result
       # can be used as an argument for #establish_connection, for easily
       # re-establishing the connection.
-      def remove_connection(spec_name, role_name = :default)
-        if role_manager = owner_to_role_manager[spec_name]
-          role = role_manager.remove_role(role_name)
+      def remove_connection(spec_name, pool_key = :default)
+        if pool_manager = owner_to_pool_manager[spec_name]
+          pool_config = pool_manager.remove_pool_config(pool_key)
 
-          if role
-            role.disconnect!
-            role.db_config.configuration_hash
+          if pool_config
+            pool_config.disconnect!
+            pool_config.db_config.configuration_hash
           end
         end
       end
 
-      # Retrieving the connection pool happens a lot, so we cache it in @owner_to_role_manager.
+      # Retrieving the connection pool happens a lot, so we cache it in @owner_to_pool_manager.
       # This makes retrieving the connection pool O(1) once the process is warm.
       # When a connection is established or removed, we invalidate the cache.
-      def retrieve_connection_pool(spec_name, role_name = :default)
-        role = owner_to_role_manager[spec_name]&.get_role(role_name)
-        role&.pool
+      def retrieve_connection_pool(spec_name, pool_key = :default)
+        pool_config = owner_to_pool_manager[spec_name]&.get_pool_config(pool_key)
+        pool_config&.pool
       end
 
       private
-        attr_reader :owner_to_role_manager
+        attr_reader :owner_to_pool_manager
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/role.rb b/activerecord/lib/active_record/connection_adapters/pool_config.rb
similarity index 94%
rename from activerecord/lib/active_record/connection_adapters/role.rb
rename to activerecord/lib/active_record/connection_adapters/pool_config.rb
index db9d3e98ee..74588409c5 100644
--- a/activerecord/lib/active_record/connection_adapters/role.rb
+++ b/activerecord/lib/active_record/connection_adapters/pool_config.rb
@@ -2,7 +2,7 @@
 
 module ActiveRecord
   module ConnectionAdapters
-    class Role # :nodoc:
+    class PoolConfig # :nodoc:
       include Mutex_m
 
       attr_reader :db_config, :connection_specification_name
@@ -60,4 +60,4 @@ module ActiveRecord
   end
 end
 
-ActiveSupport::ForkTracker.after_fork { ActiveRecord::ConnectionAdapters::Role.discard_pools! }
+ActiveSupport::ForkTracker.after_fork { ActiveRecord::ConnectionAdapters::PoolConfig.discard_pools! }
diff --git a/activerecord/lib/active_record/connection_adapters/pool_manager.rb b/activerecord/lib/active_record/connection_adapters/pool_manager.rb
new file mode 100644
index 0000000000..bd62b0970d
--- /dev/null
+++ b/activerecord/lib/active_record/connection_adapters/pool_manager.rb
@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+module ActiveRecord
+  module ConnectionAdapters
+    class PoolManager # :nodoc:
+      def initialize
+        @name_to_pool_config = {}
+      end
+
+      def pool_configs
+        @name_to_pool_config.values
+      end
+
+      def remove_pool_config(key)
+        @name_to_pool_config.delete(key)
+      end
+
+      def get_pool_config(key)
+        @name_to_pool_config[key]
+      end
+
+      def set_pool_config(key, pool_config)
+        @name_to_pool_config[key] = pool_config
+      end
+    end
+  end
+end
diff --git a/activerecord/lib/active_record/connection_adapters/resolver.rb b/activerecord/lib/active_record/connection_adapters/resolver.rb
index 89d5d50869..18700f7fcc 100644
--- a/activerecord/lib/active_record/connection_adapters/resolver.rb
+++ b/activerecord/lib/active_record/connection_adapters/resolver.rb
@@ -2,7 +2,7 @@
 
 module ActiveRecord
   module ConnectionAdapters
-    # Builds a Role from user input.
+    # Builds a PoolConfig from user input.
     class Resolver # :nodoc:
       attr_reader :configurations
 
@@ -11,17 +11,17 @@ module ActiveRecord
         @configurations = configurations
       end
 
-      # Returns an instance of Role for a given adapter.
+      # Returns an instance of PoolConfig for a given adapter.
       # Accepts a hash one layer deep that contains all connection information.
       #
       # == Example
       #
       #   config = { "production" => { "host" => "localhost", "database" => "foo", "adapter" => "sqlite3" } }
-      #   role = Resolver.new(config).resolve_role(:production)
-      #   role.db_config.configuration_hash
+      #   pool_config = Resolver.new(config).resolve_pool_config(:production)
+      #   pool_config.db_config.configuration_hash
       #   # => { host: "localhost", database: "foo", adapter: "sqlite3" }
       #
-      def resolve_role(config)
+      def resolve_pool_config(config)
         pool_name = config if config.is_a?(Symbol)
 
         db_config = resolve(config, pool_name)
@@ -53,7 +53,7 @@ module ActiveRecord
           raise AdapterNotFound, "database configuration specifies nonexistent #{db_config.adapter} adapter"
         end
 
-        Role.new(db_config.configuration_hash.delete(:name) || "primary", db_config)
+        PoolConfig.new(db_config.configuration_hash.delete(:name) || "primary", db_config)
       end
 
       # Returns fully resolved connection, accepts hash, string or symbol.
diff --git a/activerecord/lib/active_record/connection_adapters/role_manager.rb b/activerecord/lib/active_record/connection_adapters/role_manager.rb
deleted file mode 100644
index 3837cdbb0e..0000000000
--- a/activerecord/lib/active_record/connection_adapters/role_manager.rb
+++ /dev/null
@@ -1,27 +0,0 @@
-# frozen_string_literal: true
-
-module ActiveRecord
-  module ConnectionAdapters
-    class RoleManager # :nodoc:
-      def initialize
-        @name_to_role = {}
-      end
-
-      def roles
-        @name_to_role.values
-      end
-
-      def remove_role(name)
-        @name_to_role.delete(name)
-      end
-
-      def get_role(name)
-        @name_to_role[name]
-      end
-
-      def set_role(name, role)
-        @name_to_role[name] = role
-      end
-    end
-  end
-end
diff --git a/activerecord/lib/active_record/test_fixtures.rb b/activerecord/lib/active_record/test_fixtures.rb
index 30d3804ce3..665fd98c24 100644
--- a/activerecord/lib/active_record/test_fixtures.rb
+++ b/activerecord/lib/active_record/test_fixtures.rb
@@ -192,11 +192,11 @@ module ActiveRecord
         ActiveRecord::Base.connection_handlers.values.each do |handler|
           if handler != writing_handler
             handler.connection_pool_names.each do |name|
-              writing_role_manager = writing_handler.send(:owner_to_role_manager)[name]
-              writing_role = writing_role_manager.get_role(:default)
+              writing_pool_manager = writing_handler.send(:owner_to_pool_manager)[name]
+              writing_pool_config = writing_pool_manager.get_pool_config(:default)
 
-              role_manager = handler.send(:owner_to_role_manager)[name]
-              role_manager.set_role(:default, writing_role)
+              pool_manager = handler.send(:owner_to_pool_manager)[name]
+              pool_manager.set_pool_config(:default, writing_pool_config)
             end
           end
         end
diff --git a/activerecord/test/cases/connection_adapters/adapter_leasing_test.rb b/activerecord/test/cases/connection_adapters/adapter_leasing_test.rb
index 12a49513be..093d244791 100644
--- a/activerecord/test/cases/connection_adapters/adapter_leasing_test.rb
+++ b/activerecord/test/cases/connection_adapters/adapter_leasing_test.rb
@@ -40,8 +40,8 @@ module ActiveRecord
 
       def test_close
         db_config = ActiveRecord::DatabaseConfigurations::HashConfig.new("test", "primary", {})
-        role = ActiveRecord::ConnectionAdapters::Role.new("primary", db_config)
-        pool = Pool.new(role)
+        pool_config = ActiveRecord::ConnectionAdapters::PoolConfig.new("primary", db_config)
+        pool = Pool.new(pool_config)
         pool.insert_connection_for_test! @adapter
         @adapter.pool = pool
 
diff --git a/activerecord/test/cases/connection_adapters/connection_handlers_multi_role_test.rb b/activerecord/test/cases/connection_adapters/connection_handlers_multi_pool_config_test.rb
similarity index 86%
rename from activerecord/test/cases/connection_adapters/connection_handlers_multi_role_test.rb
rename to activerecord/test/cases/connection_adapters/connection_handlers_multi_pool_config_test.rb
index 292472fc36..d75045c7e7 100644
--- a/activerecord/test/cases/connection_adapters/connection_handlers_multi_role_test.rb
+++ b/activerecord/test/cases/connection_adapters/connection_handlers_multi_pool_config_test.rb
@@ -5,7 +5,7 @@ require "models/person"
 
 module ActiveRecord
   module ConnectionAdapters
-    class ConnectionHandlersMultiRoleTest < ActiveRecord::TestCase
+    class ConnectionHandlersMultiPoolConfigTest < ActiveRecord::TestCase
       self.use_transactional_tests = false
 
       fixtures :people
@@ -22,7 +22,7 @@ module ActiveRecord
       end
 
       unless in_memory_db?
-        def test_establish_connection_with_roles
+        def test_establish_connection_with_pool_configs
           previous_env, ENV["RAILS_ENV"] = ENV["RAILS_ENV"], "default_env"
 
           config = {
@@ -34,10 +34,10 @@ module ActiveRecord
           @prev_configs, ActiveRecord::Base.configurations = ActiveRecord::Base.configurations, config
 
           @writing_handler.establish_connection(:primary)
-          @writing_handler.establish_connection(:primary, :role_two)
+          @writing_handler.establish_connection(:primary, :pool_config_two)
 
           default_pool = @writing_handler.retrieve_connection_pool("primary", :default)
-          other_pool = @writing_handler.retrieve_connection_pool("primary", :role_two)
+          other_pool = @writing_handler.retrieve_connection_pool("primary", :pool_config_two)
 
           assert_not_nil default_pool
           assert_not_equal default_pool, other_pool
@@ -62,13 +62,13 @@ module ActiveRecord
           @prev_configs, ActiveRecord::Base.configurations = ActiveRecord::Base.configurations, config
 
           @writing_handler.establish_connection(:primary)
-          @writing_handler.establish_connection(:primary, :role_two)
+          @writing_handler.establish_connection(:primary, :pool_config_two)
 
           # remove default
           @writing_handler.remove_connection("primary")
 
           assert_nil @writing_handler.retrieve_connection_pool("primary")
-          assert_not_nil @writing_handler.retrieve_connection_pool("primary", :role_two)
+          assert_not_nil @writing_handler.retrieve_connection_pool("primary", :pool_config_two)
         ensure
           ActiveRecord::Base.configurations = @prev_configs
           ActiveRecord::Base.establish_connection(:arunit)
@@ -87,18 +87,19 @@ module ActiveRecord
           @prev_configs, ActiveRecord::Base.configurations = ActiveRecord::Base.configurations, config
 
           @writing_handler.establish_connection(:primary)
-          @writing_handler.establish_connection(:primary, :role_two)
+          @writing_handler.establish_connection(:primary, :pool_config_two)
 
           # connect to default
           @writing_handler.connection_pool_list.first.checkout
 
           assert @writing_handler.connected?("primary")
           assert @writing_handler.connected?("primary", :default)
-          assert_not @writing_handler.connected?("primary", :role_two)
+          assert_not @writing_handler.connected?("primary", :pool_config_two)
         ensure
           ActiveRecord::Base.configurations = @prev_configs
           ActiveRecord::Base.establish_connection(:arunit)
           ENV["RAILS_ENV"] = previous_env
+          FileUtils.rm_rf "db"
         end
       end
     end
diff --git a/activerecord/test/cases/connection_pool_test.rb b/activerecord/test/cases/connection_pool_test.rb
index 8a6e64a60c..5b0302afb3 100644
--- a/activerecord/test/cases/connection_pool_test.rb
+++ b/activerecord/test/cases/connection_pool_test.rb
@@ -13,8 +13,8 @@ module ActiveRecord
 
         # Keep a duplicate pool so we do not bother others
         @db_config = ActiveRecord::Base.connection_pool.db_config
-        @role = ActiveRecord::ConnectionAdapters::Role.new("primary", @db_config)
-        @pool = ConnectionPool.new(@role)
+        @pool_config = ActiveRecord::ConnectionAdapters::PoolConfig.new("primary", @db_config)
+        @pool = ConnectionPool.new(@pool_config)
 
         if in_memory_db?
           # Separate connections to an in-memory database create an entirely new database,
@@ -201,8 +201,8 @@ module ActiveRecord
       def test_idle_timeout_configuration
         @pool.disconnect!
         @db_config.configuration_hash.merge!(idle_timeout: "0.02")
-        role = ActiveRecord::ConnectionAdapters::Role.new("primary", @db_config)
-        @pool = ConnectionPool.new(role)
+        pool_config = ActiveRecord::ConnectionAdapters::PoolConfig.new("primary", @db_config)
+        @pool = ConnectionPool.new(pool_config)
         idle_conn = @pool.checkout
         @pool.checkin(idle_conn)
 
@@ -226,8 +226,8 @@ module ActiveRecord
       def test_disable_flush
         @pool.disconnect!
         @db_config.configuration_hash.merge!(idle_timeout: -5)
-        role = ActiveRecord::ConnectionAdapters::Role.new("primary", @db_config)
-        @pool = ConnectionPool.new(role)
+        pool_config = ActiveRecord::ConnectionAdapters::PoolConfig.new("primary", @db_config)
+        @pool = ConnectionPool.new(pool_config)
         idle_conn = @pool.checkout
         @pool.checkin(idle_conn)
 
@@ -317,7 +317,7 @@ module ActiveRecord
       end
 
       def test_checkout_behaviour
-        pool = ConnectionPool.new(@role)
+        pool = ConnectionPool.new(@pool_config)
         main_connection = pool.connection
         assert_not_nil main_connection
         threads = []
@@ -450,7 +450,7 @@ module ActiveRecord
       end
 
       def test_automatic_reconnect_restores_after_disconnect
-        pool = ConnectionPool.new(@role)
+        pool = ConnectionPool.new(@pool_config)
         assert pool.automatic_reconnect
         assert pool.connection
 
@@ -459,7 +459,7 @@ module ActiveRecord
       end
 
       def test_automatic_reconnect_can_be_disabled
-        pool = ConnectionPool.new(@role)
+        pool = ConnectionPool.new(@pool_config)
         pool.disconnect!
         pool.automatic_reconnect = false
 
@@ -723,10 +723,10 @@ module ActiveRecord
           old_config = @db_config.configuration_hash
           db_config = ActiveRecord::DatabaseConfigurations::HashConfig.new("arunit", "primary", old_config.dup)
 
-          db_config.configuration_hash[:pool] = 1 # this is safe to do, because .dupped Role also auto-dups its config
+          db_config.configuration_hash[:pool] = 1 # this is safe to do, because .dupped PoolConfig also auto-dups its config
 
-          role = ActiveRecord::ConnectionAdapters::Role.new("primary", db_config)
-          yield(pool = ConnectionPool.new(role))
+          pool_config = ActiveRecord::ConnectionAdapters::PoolConfig.new("primary", db_config)
+          yield(pool = ConnectionPool.new(pool_config))
         ensure
           pool.disconnect! if pool
         end
diff --git a/activerecord/test/cases/disconnected_test.rb b/activerecord/test/cases/disconnected_test.rb
index da90526425..b7237d11fc 100644
--- a/activerecord/test/cases/disconnected_test.rb
+++ b/activerecord/test/cases/disconnected_test.rb
@@ -14,8 +14,8 @@ class TestDisconnectedAdapter < ActiveRecord::TestCase
 
   teardown do
     return if in_memory_db?
-    role = ActiveRecord::Base.connection_config
-    ActiveRecord::Base.establish_connection(role)
+    config = ActiveRecord::Base.connection_config
+    ActiveRecord::Base.establish_connection(config)
   end
 
   unless in_memory_db?
diff --git a/activerecord/test/cases/fixtures_test.rb b/activerecord/test/cases/fixtures_test.rb
index 9c0e9e5ea6..ff939ad1ac 100644
--- a/activerecord/test/cases/fixtures_test.rb
+++ b/activerecord/test/cases/fixtures_test.rb
@@ -1414,10 +1414,10 @@ class MultipleDatabaseFixturesTest < ActiveRecord::TestCase
 
   private
     def with_temporary_connection_pool
-      role = ActiveRecord::Base.connection_handler.send(:owner_to_role_manager).fetch("primary").get_role(:default)
-      new_pool = ActiveRecord::ConnectionAdapters::ConnectionPool.new(role)
+      pool_config = ActiveRecord::Base.connection_handler.send(:owner_to_pool_manager).fetch("primary").get_pool_config(:default)
+      new_pool = ActiveRecord::ConnectionAdapters::ConnectionPool.new(pool_config)
 
-      role.stub(:pool, new_pool) do
+      pool_config.stub(:pool, new_pool) do
         yield
       end
     end
diff --git a/activerecord/test/cases/connection_specification/resolver_test.rb b/activerecord/test/cases/pool_config/resolver_test.rb
similarity index 57%
rename from activerecord/test/cases/connection_specification/resolver_test.rb
rename to activerecord/test/cases/pool_config/resolver_test.rb
index 28da6aa928..b45e2a13bd 100644
--- a/activerecord/test/cases/connection_specification/resolver_test.rb
+++ b/activerecord/test/cases/pool_config/resolver_test.rb
@@ -4,23 +4,23 @@ require "cases/helper"
 
 module ActiveRecord
   module ConnectionAdapters
-    class Role
+    class PoolConfig
       class ResolverTest < ActiveRecord::TestCase
-        def resolve(role, config = {})
+        def resolve(pool_config, config = {})
           configs = ActiveRecord::DatabaseConfigurations.new(config)
           resolver = ConnectionAdapters::Resolver.new(configs)
-          resolver.resolve(role, role).configuration_hash
+          resolver.resolve(pool_config, pool_config).configuration_hash
         end
 
-        def resolve_role(role, config = {})
+        def resolve_pool_config(pool_config, config = {})
           configs = ActiveRecord::DatabaseConfigurations.new(config)
           resolver = ConnectionAdapters::Resolver.new(configs)
-          resolver.resolve_role(role)
+          resolver.resolve_pool_config(pool_config)
         end
 
         def test_url_invalid_adapter
           error = assert_raises(LoadError) do
-            resolve_role "ridiculous://foo?encoding=utf8"
+            resolve_pool_config "ridiculous://foo?encoding=utf8"
           end
 
           assert_match "Could not load the 'ridiculous' Active Record adapter. Ensure that the adapter is spelled correctly in config/database.yml and that you've added the necessary adapter gem to your Gemfile.", error.message
@@ -28,7 +28,7 @@ module ActiveRecord
 
         def test_error_if_no_adapter_method
           error = assert_raises(AdapterNotFound) do
-            resolve_role "abstract://foo?encoding=utf8"
+            resolve_pool_config "abstract://foo?encoding=utf8"
           end
 
           assert_match "database configuration specifies nonexistent abstract adapter", error.message
@@ -38,121 +38,121 @@ module ActiveRecord
         # checks that the adapter file can be required in.
 
         def test_url_from_environment
-          role = resolve :production, "production" => "abstract://foo?encoding=utf8"
+          pool_config = resolve :production, "production" => "abstract://foo?encoding=utf8"
           assert_equal({
             adapter:  "abstract",
             host:     "foo",
             encoding: "utf8",
             name:     "production"
-          }, role)
+          }, pool_config)
         end
 
         def test_url_sub_key
-          role = resolve :production, "production" => { "url" => "abstract://foo?encoding=utf8" }
+          pool_config = resolve :production, "production" => { "url" => "abstract://foo?encoding=utf8" }
           assert_equal({
             adapter:  "abstract",
             host:     "foo",
             encoding: "utf8",
             name:     "production"
-          }, role)
+          }, pool_config)
         end
 
         def test_url_sub_key_merges_correctly
           hash = { "url" => "abstract://foo?encoding=utf8&", "adapter" => "sqlite3", "host" => "bar", "pool" => "3" }
-          role = resolve :production, "production" => hash
+          pool_config = resolve :production, "production" => hash
           assert_equal({
             adapter:  "abstract",
             host:     "foo",
             encoding: "utf8",
             pool:     "3",
             name:     "production"
-          }, role)
+          }, pool_config)
         end
 
         def test_url_host_no_db
-          role = resolve "abstract://foo?encoding=utf8"
+          pool_config = resolve "abstract://foo?encoding=utf8"
           assert_equal({
             adapter:  "abstract",
             host:     "foo",
             encoding: "utf8"
-          }, role)
+          }, pool_config)
         end
 
         def test_url_missing_scheme
-          role = resolve "foo"
-          assert_equal({ database: "foo" }, role)
+          pool_config = resolve "foo"
+          assert_equal({ database: "foo" }, pool_config)
         end
 
         def test_url_host_db
-          role = resolve "abstract://foo/bar?encoding=utf8"
+          pool_config = resolve "abstract://foo/bar?encoding=utf8"
           assert_equal({
             adapter:  "abstract",
             database: "bar",
             host:     "foo",
             encoding: "utf8"
-          }, role)
+          }, pool_config)
         end
 
         def test_url_port
-          role = resolve "abstract://foo:123?encoding=utf8"
+          pool_config = resolve "abstract://foo:123?encoding=utf8"
           assert_equal({
             adapter:  "abstract",
             port:     123,
             host:     "foo",
             encoding: "utf8"
-          }, role)
+          }, pool_config)
         end
 
         def test_encoded_password
           password = "am@z1ng_p@ssw0rd#!"
           encoded_password = URI.encode_www_form_component(password)
-          role = resolve "abstract://foo:#{encoded_password}@localhost/bar"
-          assert_equal password, role[:password]
+          pool_config = resolve "abstract://foo:#{encoded_password}@localhost/bar"
+          assert_equal password, pool_config[:password]
         end
 
         def test_url_with_authority_for_sqlite3
-          role = resolve "sqlite3:///foo_test"
-          assert_equal("/foo_test", role[:database])
+          pool_config = resolve "sqlite3:///foo_test"
+          assert_equal("/foo_test", pool_config[:database])
         end
 
         def test_url_absolute_path_for_sqlite3
-          role = resolve "sqlite3:/foo_test"
-          assert_equal("/foo_test", role[:database])
+          pool_config = resolve "sqlite3:/foo_test"
+          assert_equal("/foo_test", pool_config[:database])
         end
 
         def test_url_relative_path_for_sqlite3
-          role = resolve "sqlite3:foo_test"
-          assert_equal("foo_test", role[:database])
+          pool_config = resolve "sqlite3:foo_test"
+          assert_equal("foo_test", pool_config[:database])
         end
 
         def test_url_memory_db_for_sqlite3
-          role = resolve "sqlite3::memory:"
-          assert_equal(":memory:", role[:database])
+          pool_config = resolve "sqlite3::memory:"
+          assert_equal(":memory:", pool_config[:database])
         end
 
         def test_url_sub_key_for_sqlite3
-          role = resolve :production, "production" => { "url" => "sqlite3:foo?encoding=utf8" }
+          pool_config = resolve :production, "production" => { "url" => "sqlite3:foo?encoding=utf8" }
           assert_equal({
             adapter:  "sqlite3",
             database: "foo",
             encoding: "utf8",
             name:     "production"
-          }, role)
+          }, pool_config)
         end
 
-        def test_role_connection_specification_name_on_key_lookup
-          role = resolve_role(:readonly, "readonly" => { "adapter" => "sqlite3" })
-          assert_equal "readonly", role.connection_specification_name
+        def test_pool_config_connection_specification_name_on_key_lookup
+          pool_config = resolve_pool_config(:readonly, "readonly" => { "adapter" => "sqlite3" })
+          assert_equal "readonly", pool_config.connection_specification_name
         end
 
-        def test_role_connection_specification_name_with_inline_config
-          role = resolve_role("adapter" => "sqlite3")
-          assert_equal "primary", role.connection_specification_name, "should default to primary id"
+        def test_pool_config_connection_specification_name_with_inline_config
+          pool_config = resolve_pool_config("adapter" => "sqlite3")
+          assert_equal "primary", pool_config.connection_specification_name, "should default to primary id"
         end
 
-        def test_role_with_invalid_type
+        def test_pool_config_with_invalid_type
           assert_raises TypeError do
-            resolve_role(Object.new)
+            resolve_pool_config(Object.new)
           end
         end
       end
diff --git a/activerecord/test/cases/query_cache_test.rb b/activerecord/test/cases/query_cache_test.rb
index e35bc7010b..6e90124b81 100644
--- a/activerecord/test/cases/query_cache_test.rb
+++ b/activerecord/test/cases/query_cache_test.rb
@@ -555,10 +555,10 @@ class QueryCacheTest < ActiveRecord::TestCase
 
   private
     def with_temporary_connection_pool
-      role = ActiveRecord::Base.connection_handler.send(:owner_to_role_manager).fetch("primary").get_role(:default)
-      new_pool = ActiveRecord::ConnectionAdapters::ConnectionPool.new(role)
+      pool_config = ActiveRecord::Base.connection_handler.send(:owner_to_pool_manager).fetch("primary").get_pool_config(:default)
+      new_pool = ActiveRecord::ConnectionAdapters::ConnectionPool.new(pool_config)
 
-      role.stub(:pool, new_pool) do
+      pool_config.stub(:pool, new_pool) do
         yield
       end
     end
diff --git a/activerecord/test/cases/reaper_test.rb b/activerecord/test/cases/reaper_test.rb
index 8eab4d5807..dd9fc57299 100644
--- a/activerecord/test/cases/reaper_test.rb
+++ b/activerecord/test/cases/reaper_test.rb
@@ -59,8 +59,8 @@ module ActiveRecord
 
       def test_pool_has_reaper
         config = ActiveRecord::Base.configurations.configs_for(env_name: "arunit", spec_name: "primary")
-        role = Role.new("primary", config)
-        pool = ConnectionPool.new(role)
+        pool_config = PoolConfig.new("primary", config)
+        pool = ConnectionPool.new(pool_config)
 
         assert pool.reaper
       ensure
@@ -68,10 +68,10 @@ module ActiveRecord
       end
 
       def test_reaping_frequency_configuration
-        role = duplicated_role
-        role.db_config.configuration_hash[:reaping_frequency] = "10.01"
+        pool_config = duplicated_pool_config
+        pool_config.db_config.configuration_hash[:reaping_frequency] = "10.01"
 
-        pool = ConnectionPool.new(role)
+        pool = ConnectionPool.new(pool_config)
 
         assert_equal 10.01, pool.reaper.frequency
       ensure
@@ -79,10 +79,10 @@ module ActiveRecord
       end
 
       def test_connection_pool_starts_reaper
-        role = duplicated_role
-        role.db_config.configuration_hash[:reaping_frequency] = "0.0001"
+        pool_config = duplicated_pool_config
+        pool_config.db_config.configuration_hash[:reaping_frequency] = "0.0001"
 
-        pool = ConnectionPool.new(role)
+        pool = ConnectionPool.new(pool_config)
 
         conn, child = new_conn_in_thread(pool)
 
@@ -97,11 +97,11 @@ module ActiveRecord
       end
 
       def test_reaper_works_after_pool_discard
-        role = duplicated_role
-        role.db_config.configuration_hash[:reaping_frequency] = "0.0001"
+        pool_config = duplicated_pool_config
+        pool_config.db_config.configuration_hash[:reaping_frequency] = "0.0001"
 
         2.times do
-          pool = ConnectionPool.new(role)
+          pool = ConnectionPool.new(pool_config)
 
           conn, child = new_conn_in_thread(pool)
 
@@ -119,8 +119,8 @@ module ActiveRecord
       # This doesn't test the reaper directly, but we want to test the action
       # it would take on a discarded pool
       def test_reap_flush_on_discarded_pool
-        role = duplicated_role
-        pool = ConnectionPool.new(role)
+        pool_config = duplicated_pool_config
+        pool = ConnectionPool.new(pool_config)
 
         pool.discard!
         pool.reap
@@ -128,14 +128,14 @@ module ActiveRecord
       end
 
       def test_connection_pool_starts_reaper_in_fork
-        role = duplicated_role
-        role.db_config.configuration_hash[:reaping_frequency] = "0.0001"
+        pool_config = duplicated_pool_config
+        pool_config.db_config.configuration_hash[:reaping_frequency] = "0.0001"
 
-        pool = ConnectionPool.new(role)
+        pool = ConnectionPool.new(pool_config)
         pool.checkout
 
         pid = fork do
-          pool = ConnectionPool.new(role)
+          pool = ConnectionPool.new(pool_config)
 
           conn, child = new_conn_in_thread(pool)
           child.terminate
@@ -173,10 +173,10 @@ module ActiveRecord
       end
 
       private
-        def duplicated_role
+        def duplicated_pool_config
           old_config = ActiveRecord::Base.connection_pool.db_config.configuration_hash
           db_config = ActiveRecord::DatabaseConfigurations::HashConfig.new("arunit", "primary", old_config.dup)
-          Role.new("primary", db_config)
+          PoolConfig.new("primary", db_config)
         end
 
         def new_conn_in_thread(pool)
diff --git a/activerecord/test/cases/unconnected_test.rb b/activerecord/test/cases/unconnected_test.rb
index a53d0ec258..f9b3d79709 100644
--- a/activerecord/test/cases/unconnected_test.rb
+++ b/activerecord/test/cases/unconnected_test.rb
@@ -13,7 +13,7 @@ class TestUnconnectedAdapter < ActiveRecord::TestCase
     @specification = ActiveRecord::Base.remove_connection
 
     # Clear out connection info from other pids (like a fork parent) too
-    ActiveRecord::ConnectionAdapters::Role.discard_pools!
+    ActiveRecord::ConnectionAdapters::PoolConfig.discard_pools!
   end
 
   teardown do