fix(pg-pool): finish requests waiting for a client when the pool ends

packages/pg-pool/index.js

@@ -130,7 +130,7 @@ class Pool extends EventEmitter {
       this.log('pulse queue ended')
       return
     }
-    if (this.ending) {
+    if (this.ending && !this._pendingQueue.length) {
       this.log('pulse queue on ending')
       if (this._idle.length) {
         this._idle.slice().map((item) => {
@@ -389,7 +389,8 @@ class Pool extends EventEmitter {
     this.emit('release', err, client)
 
     // TODO(bmc): expose a proper, public interface _queryable and _ending
-    if (err || this.ending || !client._queryable || client._ending || client._poolUseCount >= this.options.maxUses) {
+    const draining = this.ending && !this._pendingQueue.length
+    if (err || draining || !client._queryable || client._ending || client._poolUseCount >= this.options.maxUses) {
       if (client._poolUseCount >= this.options.maxUses) {
         this.log('remove expended client')
       }

packages/pg-pool/test/ending.js

@@ -38,6 +38,21 @@ describe('pool ending', () => {
     })
   )
 
+  it('finishes queries waiting for a client when the pool ends', async () => {
+    const pool = new Pool({ max: 1 })
+    const client = await pool.connect()
+    const queries = [1, 2, 3].map((n) => pool.query('SELECT $1::int AS n', [n]))
+    const ended = pool.end()
+    client.release()
+
+    const results = await Promise.all(queries)
+    await ended
+
+    expect(results.map((x) => x.rows[0].n)).to.eql([1, 2, 3])
+    expect(pool.totalCount).to.equal(0)
+    expect(pool.ended).to.equal(true)
+  })
+
   it('pool.end() - finish pending queries', async () => {
     const pool = new Pool({ max: 20 })
     let completed = 0