PostgreSQL adapter doesn't allow spaces in table names if no schema or quotes

[Jerph]

Steps to reproduce

Create, attempt to use, or schema-dump a PostgreSQL table with a space in the name, e.g. create_table 'work orders'.

Expected behavior

It should treat the entire string as the table name.

Actual behavior

It uses the first word or segment before the space as the schema, and the rest as the table name.

This is a bug in the regex used for parsing the schema/table name. You can work around it by using quotes ("work orders"), which is reasonable and necessary when you specify a schema ('"my_schema"."work orders"). It is not necessary for the mysql or sqlite adapters, though, and causes friction when you don't use schemas.

System configuration

Rails version: tested with 4.2.7 and master, probably introduced here

Ruby version: 2.3.1

[maclover7]

Per discussion in #26722, the plan is to issue a warning if there is a space in the table name.

cc @matthewd