chore: check if is the same pid

Author: cesco69

packages/pg-pool/test/prioritizing-prepared-client.js

@@ -15,13 +15,17 @@ describe('prioritizing prepared client', () => {
 
       let res
 
-      res = yield pool.query({ text: 'SELECT $1::text as name', values: ['hi'], name: 'foo' })
+      res = yield pool.query({ text: 'SELECT $1::text as name, pg_backend_pid() as pid', values: ['hi'], name: 'foo' })
       expect(res.rows[0].name).to.equal('hi')
       expect(pool._idle.length).to.equal(1)
+      const firstPid = res.rows[0].pid
 
-      res = yield pool.query({ text: 'SELECT $1::text as name', values: ['ho'], name: 'foo' })
+      res = yield pool.query({ text: 'SELECT $1::text as name, pg_backend_pid() as pid', values: ['ho'], name: 'foo' })
       expect(res.rows[0].name).to.equal('ho')
       expect(pool._idle.length).to.equal(1)
+      const secondPid = res.rows[0].pid
+
+      expect(firstPid).to.equal(secondPid)
 
       pool.end()
     })