upsert in contention test failed on mac

[hychen]

env

• postgresql.app for mac (pg version 9.3.3)
• pgrest (commit 375cb92)

Step to reproduce

$ npm test
....
in contention
◦ @fixme: add test pupose here.: deprecated api, use PLX instead
null
1) @fixme: add test pupose here.
pgerror [Error: connection pointer is NULL
]
2) "after each" hook

32 passing (13s)
10 pending
2 failing

1. Upsert in contention @fixme: add test pupose here.:
   Uncaught Error: connection pointer is NULL

  at Connection.<anonymous> (/Users/hychen/project/pgrest/node_modules/plv8x/node_modules/pg/lib/native/index.js:202:17)
  at Connection.EventEmitter.emit (events.js:95:17)

2. Upsert "after each" hook:
   Uncaught Error: connection pointer is NULL

[clkao]

it seems this test crashes the postgres process on macosx

[littleq0903]

same problem here.