Fail to parse with trailing errors

Signed-off-by: Casey Dahlin <cdahlin@redhat.com>
Don't release a NULL value when cleaning up parse errors

Signed-off-by: Casey Dahlin <cdahlin@redhat.com>
New tests for parser errors

Signed-off-by: Casey Dahlin <cdahlin@redhat.com>
Detect early parser failure

Signed-off-by: Casey Dahlin <cdahlin@redhat.com>