Deprecate to_h and to_legacy_hash

These should have been deprecated when I added them but for some reason
I didn't.

As we move away from passing hashes around we no longer need these
methods, and since we no longer use configuration hashes as database
configuration we can deprecate this in favor of using the database
configuration objects and access the connection hashes from there.

Co-authored-by: John Crepezzi <john.crepezzi@gmail.com>

activerecord/lib/active_record/database_configurations.rb

@@ -79,12 +79,11 @@ module ActiveRecord
 
     # Returns the DatabaseConfigurations object as a Hash.
     def to_h
-      configs = configurations.reverse.inject({}) do |memo, db_config|
-        memo.merge(db_config.to_legacy_hash)
+      configurations.inject({}) do |memo, db_config|
+        memo.merge(db_config.env_name => db_config.configuration_hash.stringify_keys)
       end
-
-      Hash[configs.to_a.reverse]
     end
+    deprecate to_h: "You can use `ActiveRecord::Base.configurations.configs_for(env_name: 'env', spec_name: 'primary').configuration_hash` to get the configuration hashes."
 
     # Checks if the application's configurations are empty.
     #

activerecord/lib/active_record/database_configurations/database_config.rb

@@ -38,10 +38,6 @@ module ActiveRecord
         false
       end
 
-      def to_legacy_hash
-        { env_name => configuration_hash.stringify_keys }
-      end
-
       def for_current_env?
         env_name == ActiveRecord::ConnectionHandling::DEFAULT_ENV.call
       end

activerecord/test/cases/connection_adapters/merge_and_resolve_default_url_config_test.rb

@@ -17,9 +17,9 @@ module ActiveRecord
         ENV["RAILS_ENV"] = @previous_rails_env
       end
 
-      def resolve_config(config)
+      def resolve_config(config, env_name = ActiveRecord::ConnectionHandling::DEFAULT_ENV.call)
         configs = ActiveRecord::DatabaseConfigurations.new(config)
-        configs.to_h
+        configs.configs_for(env_name: env_name, spec_name: "primary")&.configuration_hash
       end
 
       def resolve_spec(spec, config)
@@ -116,16 +116,21 @@ module ActiveRecord
 
       def test_jdbc_url
         config   = { "production" => { "url" => "jdbc:postgres://localhost/foo" } }
-        actual   = resolve_config(config)
-        assert_equal config, actual
+        actual   = resolve_config(config, "production")
+        assert_equal config["production"].symbolize_keys, actual
       end
 
       def test_environment_does_not_exist_in_config_url_does_exist
         ENV["DATABASE_URL"] = "postgres://localhost/foo"
-        config      = { "not_default_env" => {  "adapter" => "not_postgres", "database" => "not_foo" } }
-        actual      = resolve_config(config)
-        expect_prod = { "adapter" => "postgresql", "database" => "foo", "host" => "localhost" }
-        assert_equal expect_prod, actual["default_env"]
+        config      = { "not_default_env" => { "adapter" => "not_postgres", "database" => "not_foo" } }
+        actual      = resolve_config(config, "default_env")
+        expect_prod = {
+          adapter: "postgresql",
+          database: "foo",
+          host: "localhost"
+        }
+
+        assert_equal expect_prod, actual
       end
 
       def test_url_with_hyphenated_scheme
@@ -138,38 +143,38 @@ module ActiveRecord
 
       def test_string_connection
         config   = { "default_env" => "postgres://localhost/foo" }
-        actual   = resolve_config(config)
-        expected = { "default_env" =>
-                     { "adapter"  => "postgresql",
-                       "database" => "foo",
-                       "host"     => "localhost"
-                      }
-                    }
+        actual   = resolve_config(config, "default_env")
+        expected = {
+          adapter: "postgresql",
+          database: "foo",
+          host: "localhost"
+        }
+
         assert_equal expected, actual
       end
 
       def test_url_sub_key
         config   = { "default_env" => { "url" => "postgres://localhost/foo" } }
         actual   = resolve_config(config)
-        expected = { "default_env" =>
-                     { "adapter"  => "postgresql",
-                       "database" => "foo",
-                       "host"     => "localhost"
-                      }
-                    }
+        expected = {
+          adapter: "postgresql",
+          database: "foo",
+          host: "localhost"
+        }
+
         assert_equal expected, actual
       end
 
       def test_hash
         config = { "production" => { "adapter" => "postgres", "database" => "foo" } }
-        actual = resolve_config(config)
-        assert_equal config, actual
+        actual = resolve_config(config, "production")
+        assert_equal config["production"].symbolize_keys, actual
       end
 
       def test_blank
         config = {}
-        actual = resolve_config(config)
-        assert_equal config, actual
+        actual = resolve_config(config, "default_env")
+        assert_nil actual
       end
 
       def test_blank_with_database_url
@@ -177,17 +182,13 @@ module ActiveRecord
 
         config   = {}
         actual   = resolve_config(config)
-        expected = { "adapter"  => "postgresql",
-                     "database" => "foo",
-                     "host"     => "localhost" }
-        assert_equal expected, actual["default_env"]
-        assert_nil actual["production"]
-        assert_nil actual["development"]
-        assert_nil actual["test"]
-        assert_nil actual[:default_env]
-        assert_nil actual[:production]
-        assert_nil actual[:development]
-        assert_nil actual[:test]
+        expected = {
+          adapter: "postgresql",
+          database: "foo",
+          host: "localhost"
+        }
+
+        assert_equal expected, actual
       end
 
       def test_blank_with_database_url_with_rails_env
@@ -196,20 +197,13 @@ module ActiveRecord
 
         config   = {}
         actual   = resolve_config(config)
-        expected = { "adapter"  => "postgresql",
-                     "database" => "foo",
-                     "host"     => "localhost" }
+        expected = {
+          adapter: "postgresql",
+          database: "foo",
+          host: "localhost"
+        }
 
-        assert_equal expected, actual["not_production"]
-        assert_nil actual["production"]
-        assert_nil actual["default_env"]
-        assert_nil actual["development"]
-        assert_nil actual["test"]
-        assert_nil actual[:default_env]
-        assert_nil actual[:not_production]
-        assert_nil actual[:production]
-        assert_nil actual[:development]
-        assert_nil actual[:test]
+        assert_equal expected, actual
       end
 
       def test_blank_with_database_url_with_rack_env
@@ -218,20 +212,13 @@ module ActiveRecord
 
         config   = {}
         actual   = resolve_config(config)
-        expected = { "adapter"  => "postgresql",
-                     "database" => "foo",
-                     "host"     => "localhost" }
+        expected = {
+          adapter: "postgresql",
+          database: "foo",
+          host: "localhost"
+        }
 
-        assert_equal expected, actual["not_production"]
-        assert_nil actual["production"]
-        assert_nil actual["default_env"]
-        assert_nil actual["development"]
-        assert_nil actual["test"]
-        assert_nil actual[:default_env]
-        assert_nil actual[:not_production]
-        assert_nil actual[:production]
-        assert_nil actual[:development]
-        assert_nil actual[:test]
+        assert_equal expected, actual
       end
 
       def test_database_url_with_ipv6_host_and_port
@@ -239,11 +226,14 @@ module ActiveRecord
 
         config   = {}
         actual   = resolve_config(config)
-        expected = { "adapter"  => "postgresql",
-                     "database" => "foo",
-                     "host"     => "::1",
-                     "port"     => 5454 }
-        assert_equal expected, actual["default_env"]
+        expected = {
+          adapter: "postgresql",
+          database: "foo",
+          host: "::1",
+          port: 5454
+        }
+
+        assert_equal expected, actual
       end
 
       def test_url_sub_key_with_database_url
@@ -251,12 +241,12 @@ module ActiveRecord
 
         config   = { "default_env" => { "url" => "postgres://localhost/foo" } }
         actual   = resolve_config(config)
-        expected = { "default_env" =>
-                    { "adapter" => "postgresql",
-                       "database" => "foo",
-                       "host"     => "localhost"
-                      }
-                    }
+        expected = {
+          adapter: "postgresql",
+          database: "foo",
+          host: "localhost"
+        }
+
         assert_equal expected, actual
       end
 
@@ -264,19 +254,21 @@ module ActiveRecord
         ENV["DATABASE_URL"] = "postgres://localhost/baz"
 
         config   = { "default_env" => { "database" => "foo" }, "other_env" => { "url" => "postgres://foohost/bardb" } }
-        actual   = resolve_config(config)
-        expected = { "default_env" =>
-                     { "database" => "baz",
-                      "adapter" => "postgresql",
-                      "host" => "localhost"
-                     },
-                     "other_env" =>
-                      { "adapter" => "postgresql",
-                       "database" => "bardb",
-                       "host"     => "foohost"
-                      }
-                    }
-        assert_equal expected, actual
+        expected = {
+          default_env: {
+            database: "baz",
+            adapter: "postgresql",
+            host: "localhost"
+          },
+          other_env: {
+            adapter: "postgresql",
+            database: "bardb",
+            host: "foohost"
+          }
+        }
+
+        assert_equal expected[:default_env], resolve_config(config, "default_env")
+        assert_equal expected[:other_env], resolve_config(config, "other_env")
       end
 
       def test_merge_no_conflicts_with_database_url
@@ -284,13 +276,13 @@ module ActiveRecord
 
         config   = { "default_env" => { "pool" => "5" } }
         actual   = resolve_config(config)
-        expected = { "default_env" =>
-                     { "adapter"  => "postgresql",
-                       "database" => "foo",
-                       "host"     => "localhost",
-                       "pool"     => "5"
-                      }
-                    }
+        expected = {
+          adapter: "postgresql",
+          database: "foo",
+          host: "localhost",
+          pool: "5"
+        }
+
         assert_equal expected, actual
       end
 
@@ -299,13 +291,13 @@ module ActiveRecord
 
         config   = { "default_env" => { "adapter" => "NOT-POSTGRES", "database" => "NOT-FOO", "pool" => "5" } }
         actual   = resolve_config(config)
-        expected = { "default_env" =>
-                     { "adapter"  => "postgresql",
-                       "database" => "foo",
-                       "host"     => "localhost",
-                       "pool"     => "5"
-                      }
-                    }
+        expected = {
+          adapter: "postgresql",
+          database: "foo",
+          host: "localhost",
+          pool: "5"
+        }
+
         assert_equal expected, actual
       end
 
@@ -314,13 +306,13 @@ module ActiveRecord
 
         config   = { "default_env" => { "adapter" => "postgresql", "pool" => "5" } }
         actual   = resolve_config(config)
-        expected = { "default_env" =>
-                     { "adapter"  => "postgresql",
-                       "database" => "foo",
-                       "host"     => "localhost",
-                       "pool"     => "5"
-                     }
+        expected = {
+          adapter: "postgresql",
+          database: "foo",
+          host: "localhost",
+          pool: "5"
         }
+
         assert_equal expected, actual
       end
 
@@ -329,12 +321,11 @@ module ActiveRecord
 
         config   = { "default_env" => { "pool" => 5 } }
         actual   = resolve_config(config)
-        expected = { "default_env" =>
-                     { "adapter"  => "postgresql",
-                       "database" => "foo",
-                       "host"     => "localhost",
-                       "pool"     => 5
-                     }
+        expected = {
+          adapter: "postgresql",
+          database: "foo",
+          host: "localhost",
+          pool: 5
         }
 
         assert_equal expected, actual

activerecord/test/cases/database_configurations_test.rb

@@ -48,11 +48,13 @@ class DatabaseConfigurationsTest < ActiveRecord::TestCase
     assert_equal "primary", config.spec_name
   end
 
-  def test_to_h_turns_db_config_object_back_into_a_hash
+  def test_to_h_turns_db_config_object_back_into_a_hash_and_is_deprecated
     configs = ActiveRecord::Base.configurations
     assert_equal "ActiveRecord::DatabaseConfigurations", configs.class.name
-    assert_equal "Hash", configs.to_h.class.name
-    assert_equal ["arunit", "arunit2", "arunit_without_prepared_statements"], ActiveRecord::Base.configurations.to_h.keys.sort
+    assert_deprecated do
+      assert_equal "Hash", configs.to_h.class.name
+      assert_equal ["arunit", "arunit2", "arunit_without_prepared_statements"], ActiveRecord::Base.configurations.to_h.keys.sort
+    end
   end
 end
 
@@ -73,9 +75,11 @@ class LegacyDatabaseConfigurationsTest < ActiveRecord::TestCase
     end
   end
 
-  def test_can_turn_configurations_into_a_hash
-    assert ActiveRecord::Base.configurations.to_h.is_a?(Hash), "expected to be a hash but was not."
-    assert_equal ["arunit", "arunit2", "arunit_without_prepared_statements"].sort, ActiveRecord::Base.configurations.to_h.keys.sort
+  def test_can_turn_configurations_into_a_hash_and_is_deprecated
+    assert_deprecated do
+      assert ActiveRecord::Base.configurations.to_h.is_a?(Hash), "expected to be a hash but was not."
+      assert_equal ["arunit", "arunit2", "arunit_without_prepared_statements"].sort, ActiveRecord::Base.configurations.to_h.keys.sort
+    end
   end
 
   def test_each_is_deprecated