Limbo does not enforce primary key uniqueness on PKs that are not rowid aliases

[jussisaurio]

sqlite> create table foo (pk TEXT PRIMARY KEY);
sqlite> insert into foo values ('lol');
sqlite> insert into foo values ('lol');
Runtime error: UNIQUE constraint failed: foo.pk (19)

sqlite> create table foo_int (pk INT PRIMARY KEY);
sqlite> insert into foo_int values (1);
sqlite> insert into foo_int values (1);
Runtime error: UNIQUE constraint failed: foo_int.pk (19)

limbo> create table foo (pk TEXT PRIMARY KEY);
limbo> insert into foo values ('lol');
limbo> insert into foo values ('lol');

limbo> create table foo_int (pk INT PRIMARY KEY);
limbo> insert into foo_int values (1);
limbo> insert into foo_int values (1);

limbo> create table foo_rowid_alias (pk INTEGER PRIMARY KEY);
limbo> insert into foo_rowid_alias values (1);
limbo> insert into foo_rowid_alias values (1);
Runtime error: UNIQUE constraint failed: foo_rowid_alias.pk (19)