Fix build failures related to the new ENV options in yml

activerecord/lib/active_record/connection_adapters/connection_specification.rb

@@ -48,11 +48,11 @@ def resolve_env_connection(spec) # :nodoc:
           # an environment key or a url spec. So we support both for
           # now but it would be nice to limit the environment key only
           # for symbols.
-          spec = configurations.fetch(spec.to_s) do
+          config = configurations.fetch(spec.to_s) do
             resolve_string_connection(spec) if spec.is_a?(String)
           end
-          raise(AdapterNotSpecified, "#{spec} database is not configured") unless spec
-          resolve_connection spec
+          raise(AdapterNotSpecified, "#{spec} database is not configured") unless config
+          resolve_connection config
         end
 
         def resolve_hash_connection(spec) # :nodoc:

activerecord/lib/active_record/railtie.rb

@@ -56,7 +56,7 @@ class Railtie < Rails::Railtie # :nodoc:
           resolver = ActiveRecord::ConnectionAdapters::ConnectionSpecification::Resolver.new(configuration)
 
           configuration.each do |key, value|
-            configuration[key] = resolver.resolve(value) if value
+            configuration[key] = resolver.resolve(value).config.stringify_keys if value
           end
 
           ActiveRecord::Tasks::DatabaseTasks.database_configuration = configuration

railties/test/isolation/abstract_unit.rb

@@ -117,6 +117,24 @@ def build_app(options = {})
         end
       end
 
+      File.open("#{app_path}/config/database.yml", "w") do |f|
+        f.puts <<-YAML
+        default: &default
+          adapter: sqlite3
+          pool: 5
+          timeout: 5000
+        development:
+          <<: *default
+          database: db/development.sqlite3
+        test:
+          <<: *default
+          database: db/test.sqlite3
+        production:
+          <<: *default
+          database: db/production.sqlite3
+        YAML
+      end
+
       add_to_config <<-RUBY
         config.eager_load = false
         config.session_store :cookie_store, key: "_myapp_session"