fix(pg-cursor): clear query_timeout when the cursor finishes

packages/pg-cursor/index.js

@@ -151,6 +151,17 @@ class Cursor extends EventEmitter {
     this._sendRows()
     this.state = 'done'
     this.emit('end', this._result)
+    this._finish(null, this._result)
+  }
+
+  // Call the Submittable callback the client set on this cursor, at most once. The client wraps it
+  // to clear its `query_timeout` timer, which otherwise fires after the cursor is done.
+  _finish(err, result) {
+    const callback = this.callback
+    this.callback = null
+    if (typeof callback === 'function') {
+      callback(err, result)
+    }
   }
 
   handleEmptyQuery() {
@@ -185,6 +196,7 @@ class Cursor extends EventEmitter {
       queuedCallback.call(this, msg)
     }
     this._queue.length = 0
+    this._finish(msg)
 
     if (this.listenerCount('error') > 0) {
       // only dispatch error events if we have a listener

packages/pg-cursor/test/query-timeout.js

@@ -0,0 +1,37 @@
+'use strict'
+const assert = require('assert')
+const Cursor = require('../')
+const pg = require('pg')
+
+const text = 'SELECT generate_series as num FROM generate_series(0, 4)'
+const wait = (ms) => new Promise((resolve) => setTimeout(resolve, ms))
+
+describe('cursor with query_timeout', function () {
+  beforeEach(async function () {
+    this.client = new pg.Client({ query_timeout: 100 })
+    await this.client.connect()
+  })
+
+  afterEach(async function () {
+    await this.client.end()
+  })
+
+  it('does not report a read timeout after the cursor is done', async function () {
+    const calls = []
+    const cursor = this.client.query(new Cursor(text), (err) => calls.push(err))
+    const rows = await cursor.read(100)
+    assert.equal(rows.length, 5)
+    await cursor.close()
+    await wait(200)
+    assert.deepEqual(calls, [null])
+  })
+
+  it('does not report a read timeout after the cursor errored', async function () {
+    const calls = []
+    const cursor = this.client.query(new Cursor('SELECT 1 / 0'), (err) => calls.push(err))
+    await assert.rejects(cursor.read(1), /division by zero/)
+    await wait(200)
+    assert.equal(calls.length, 1)
+    assert.match(calls[0].message, /division by zero/)
+  })
+})