Clarify 'database does not exist' message and implementation.

* Clarify what the situation is and what to do.
* Advise loading schema using `rake db:setup` instead of migrating.
* Use a rescue in the initializer rather than extending the error
  message in-place.
* Preserve the original backtrace of other errors by using `raise`
  rather than raising again with `raise error`.

References 0ec45cd15d0a2f5aebc75e23d841b6c12f3ba763

1 files changed, 14 insertions, 9 deletions

diff --git a/activerecord/lib/active_record/railtie.rb b/activerecord/lib/active_record/railtie.rb
index 11b564f8f9..a4ceacbf44 100644
--- a/activerecord/lib/active_record/railtie.rb
+++ b/activerecord/lib/active_record/railtie.rb
@@ -116,17 +116,22 @@ module ActiveRecord
     # and then establishes the connection.
     initializer "active_record.initialize_database" do |app|
       ActiveSupport.on_load(:active_record) do
+        self.configurations = Rails.application.config.database_configuration
 
-        class ActiveRecord::NoDatabaseError
-          remove_possible_method :extend_message
-          def extend_message(message)
-            message << "Run `$ bin/rake db:create db:migrate` to create your database"
-            message
-          end
-        end
+        begin
+          establish_connection
+        rescue ActiveRecord::NoDatabaseError
+          warn <<-end_warning
+Oops - You have a database configured, but it doesn't exist yet!
 
-        self.configurations = Rails.application.config.database_configuration
-        establish_connection
+Here's how to get started:
+
+  1. Configure your database in config/database.yml.
+  2. Run `bin/rake db:create` to create the database.
+  3. Run `bin/rake db:setup` to load your database schema.
+end_warning
+          raise
+        end
       end
     end