Raise NoDatabaseError when db does not exist

Building on the work of #13427 this PR adds a helpful error message to the adapters: mysql, mysql2, and sqlite3

3 files changed, 18 insertions, 0 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb b/activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb
index e790f731ea..6d8e994654 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql2_adapter.rb
@@ -18,6 +18,12 @@ module ActiveRecord
       client = Mysql2::Client.new(config)
       options = [config[:host], config[:username], config[:password], config[:database], config[:port], config[:socket], 0]
       ConnectionAdapters::Mysql2Adapter.new(client, logger, options, config)
+    rescue Mysql2::Error => error
+      if error.message.include?("Unknown database")
+        raise ActiveRecord::NoDatabaseError.new(error.message)
+      else
+        raise error
+      end
     end
   end
 
diff --git a/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
index 760f1435eb..7dbaa272a3 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
@@ -34,6 +34,12 @@ module ActiveRecord
       default_flags |= Mysql::CLIENT_FOUND_ROWS if Mysql.const_defined?(:CLIENT_FOUND_ROWS)
       options = [host, username, password, database, port, socket, default_flags]
       ConnectionAdapters::MysqlAdapter.new(mysql, logger, options, config)
+    rescue Mysql::Error => error
+      if error.message.include?("Unknown database")
+        raise ActiveRecord::NoDatabaseError.new(error.message)
+      else
+        raise error
+      end
     end
   end
 
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
index a02eda5603..92bb70ba53 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
@@ -31,6 +31,12 @@ module ActiveRecord
       db.busy_timeout(ConnectionAdapters::SQLite3Adapter.type_cast_config_to_integer(config[:timeout])) if config[:timeout]
 
       ConnectionAdapters::SQLite3Adapter.new(db, logger, config)
+    rescue Errno::ENOENT => error
+      if error.message.include?("No such file or directory")
+        raise ActiveRecord::NoDatabaseError.new(error.message)
+      else
+        raise error
+      end
     end
   end